Cyperus difformis L.is a troublesome weed in paddy fields and has attracted attention due to its resistance to acetohydroxyacid synthase(AHAS)inhibitors.It was found that the amino acid mutation in AHAS was the primar...Cyperus difformis L.is a troublesome weed in paddy fields and has attracted attention due to its resistance to acetohydroxyacid synthase(AHAS)inhibitors.It was found that the amino acid mutation in AHAS was the primary cause for the resistance of Cyperus difformis.However,the effect of different mutations on AHAS function is not clear in Cyperus difformis.To confirm the effect of mutations on AHAS function,six biotypes were collected,including Pro197Arg,Pro197Ser,Pro197Leu,Asp376Glu,Trp574Leu and wild type,from Hunan,Anhui,Jiangxi and Jiangsu provinces,China and the function of AHAS was characterized.The AHAS in vitro inhibition assay results indicated that the mutations decreased the sensitivity of AHAS to pyrazosulfuron-ethyl,in which the I_(50)(the half maximal inhibitory concentration)of wild type AHAS was 0.04μmol L^(-1)and Asp376Glu,Pro197Leu,Pro197Arg,Pro197Ser and Trp574Leu mutations were 3.98,11.50,40.38,38.19 and 311.43μmol L^(-1),respectively.In the determination of enzyme kinetics parameters,the Km and the maximum reaction velocity(Vmax)of the wild type were 5.18 mmol L^(-1)and 0.12 nmol mg^(-1)min^(-1),respectively,and the Km values of AHAS with Asp376Glu,Trp574Leu,Pro197Leu and Pro197Ser mutations were 0.38-0.93 times of the wild type.The Km value of the Pro197Arg mutation was 1.14times of the wild type,and the Vmax values of the five mutations were 1.17-3.33-fold compared to the wild type.It was found that the mutations increased the affinity of AHAS to the substrate,except for the Pro197Arg mutation.At a concentration of 0.0032-100 mmol L^(-1)branched-chain amino acids(BCAAs),the sensitivity of the other four mutant AHAS biotypes to feedback inhibition decreased,except for the Pro197Arg mutation.This study elucidated the effect of different mutations on AHAS function in Cyperus difformis and provided ideas for further study of resistance development.展开更多
Lesion mimic often exhibits leaf disease-like symptoms even in the absence of pathogen infection,and is characterized by a hypersensitive-response(HR)that closely linked to plant disease resistance.Despite this,only a...Lesion mimic often exhibits leaf disease-like symptoms even in the absence of pathogen infection,and is characterized by a hypersensitive-response(HR)that closely linked to plant disease resistance.Despite this,only a few lesion mimic genes have been identified in wheat.In this investigation,a lesion mimic wheat mutant named je0297 was discovered,showing no alteration in yield components when compared to the wild type(WT).Segregation ratio analysis of the F_(2)individuals resulting from the cross between the WT and the mutant revealed that the lesion mimic was governed by a single recessive gene in je0297.Using Bulked segregant analysis(BSA)and exome capture sequencing,we mapped the lesion mimic gene designated as lm6 to chromosome 6BL.Further gene fine mapping using 3315 F_(2)individuals delimited the lm6 within a 1.18 Mb region.Within this region,we identified 16 high-confidence genes,with only two displaying mutations in je0297.Notably,one of the two genes,responsible for encoding flavonol synthase,exhibited altered expression levels.Subsequent phenotype analysis of TILLING mutants confirmed that the gene encoding flavonol synthase was indeed the causal gene for lm6.Transcriptome sequencing analysis revealed that the DEGs between the WT and mutant were significantly enriched in KEGG pathways related to flavonoid biosynthesis,including flavone and flavonol biosynthesis,isoflavonoid biosynthesis,and flavonoid biosynthesis pathways.Furthermore,more than 30 pathogen infection-related(PR)genes exhibited upregulation in the mutant.Corresponding to this expression pattern,the flavonoid content in je0297 showed a significant decrease in the 4^(th)leaf,accompanied by a notable accumulation of reactive oxygen,which likely contributed to the development of lesion mimic in the mutant.This investigation enhances our comprehension of cell death signaling pathways and provides a valuable gene resource for the breeding of disease-resistant wheat.展开更多
Sucrose phosphate synthase(SPS)is a rate-limiting enzyme that works in conjunction with sucrose-6-phosphate phosphatase(SPP)for sucrose synthesis,and it plays an essential role in energy provisioning during growth and...Sucrose phosphate synthase(SPS)is a rate-limiting enzyme that works in conjunction with sucrose-6-phosphate phosphatase(SPP)for sucrose synthesis,and it plays an essential role in energy provisioning during growth and development in plants as well as improving fruit quality.However,studies on the systematic analysis and evolutionary pattern of the SPS gene family in apple are still lacking.In the present study,a total of seven MdSPS and four MdSPP genes were identified from the Malus domestica genome GDDH13 v1.1.The gene structures and their promoter cis-elements,protein conserved motifs,subcellular localizations,physiological functions and biochemical properties were analyzed.A chromosomal location and gene-duplication analysis demonstrated that whole-genome duplication(WGD)and segmental duplication played vital roles in MdSPS gene family expansion.The Ka/Ks ratio of pairwise MdSPS genes indicated that the members of this family have undergone strong purifying selection during domestication.Furthermore,three SPS gene subfamilies were classified based on phylogenetic relationships,and old gene duplications and significantly divergent evolutionary rates were observed among the SPS gene subfamilies.In addition,a major gene related to sucrose accumulation(MdSPSA2.3)was identified according to the highly consistent trends in the changes of its expression in four apple varieties(‘Golden Delicious’,‘Fuji’,‘Qinguan’and‘Honeycrisp’)and the correlation between gene expression and soluble sugar content during fruit development.Furthermore,the virus-induced silencing of MdSPSA2.3 confirmed its function in sucrose accumulation in apple fruit.The present study lays a theoretical foundation for better clarifying the biological functions of the MdSPS genes during apple fruit development.展开更多
Treatment with metformin can lead to the recovery of pleiotropic biological activities after spinal cord injury.However,its effect on spinal cord injury in aged mice remains unclear.Considering the essential role of a...Treatment with metformin can lead to the recovery of pleiotropic biological activities after spinal cord injury.However,its effect on spinal cord injury in aged mice remains unclear.Considering the essential role of angiogenesis during the regeneration process,we hypothesized that metformin activates the adenosine monophosphate-activated protein kinase/endothelial nitric oxide synthase pathway in endothelial cells,thereby promoting microvascular regeneration in aged mice after spinal cord injury.In this study,we established young and aged mouse models of contusive spinal cord injury using a modified Allen method.We found that aging hindered the recovery of neurological function and the formation of blood vessels in the spinal cord.Treatment with metformin promoted spinal cord microvascular endothelial cell migration and blood vessel formation in vitro.Furthermore,intraperitoneal injection of metformin in an in vivo model promoted endothelial cell proliferation and increased the density of new blood vessels in the spinal cord,thereby improving neurological function.The role of metformin was reversed by compound C,an adenosine monophosphate-activated protein kinase inhibitor,both in vivo and in vitro,suggesting that the adenosine monophosphate-activated protein kinase/endothelial nitric oxide synthase pathway likely regulates metformin-mediated angiogenesis after spinal cord injury.These findings suggest that metformin promotes vascular regeneration in the injured spinal cord by activating the adenosine monophosphate-activated protein kinase/endothelial nitric oxide synthase pathway,thereby improving the neurological function of aged mice after spinal cord injury.展开更多
Dysfunction of neuronal nitric oxide synthase contributes to neurotoxicity,which triggers cell death in various neuropathological diseases,including epilepsy.Studies have shown that inhibition of neuronal nitric oxide...Dysfunction of neuronal nitric oxide synthase contributes to neurotoxicity,which triggers cell death in various neuropathological diseases,including epilepsy.Studies have shown that inhibition of neuronal nitric oxide synthase activity increases the epilepsy threshold,that is,has an anticonvulsant effect.However,the exact role and potential mechanism of neuronal nitric oxide synthase in seizures are still unclear.In this study,we performed RNA sequencing,functional enrichment analysis,and weighted gene coexpression network analysis of the hippocampus of tremor rats,a rat model of genetic epilepsy.We found damaged hippocampal mitochondria and abnormal succinate dehydrogenase level and Na+-K+-ATPase activity.In addition,we used a pilocarpine-induced N2a cell model to mimic epileptic injury.After application of neuronal nitric oxide synthase inhibitor 7-nitroindazole,changes in malondialdehyde,lactate dehydrogenase and superoxide dismutase,which are associated with oxidative stress,were reversed,and the increase in reactive oxygen species level was reversed by 7-nitroindazole or reactive oxygen species inhibitor N-acetylcysteine.Application of 7-nitroindazole or N-acetylcysteine downregulated the expression of caspase-3 and cytochrome c and reversed the apoptosis of epileptic cells.Furthermore,7-nitroindazole or N-acetylcysteine downregulated the abnormally high expression of NLRP3,gasdermin-D,interleukin-1βand interleukin-18.This indicated that 7-nitroindazole and N-acetylcysteine each reversed epileptic cell death.Taken together,our findings suggest that the neuronal nitric oxide synthase/reactive oxygen species pathway is involved in pyroptosis of epileptic cells,and inhibiting neuronal nitric oxide synthase activity or its induced oxidative stress may play a neuroprotective role in epilepsy.展开更多
Sesquiterpenes are the major pharmacodynamic components of agarwood,a precious traditional Chinese medicine obtained from the resinous portions of Aquilaria sinensis trees that form in response to environmental stress...Sesquiterpenes are the major pharmacodynamic components of agarwood,a precious traditional Chinese medicine obtained from the resinous portions of Aquilaria sinensis trees that form in response to environmental stressors.To characterize the sesquiterpene synthases responsible for sesquiterpene production in A.sinensis,a bioinformatics analysis of the genome of A.sinensis identifi ed six new terpene synthase genes,and 16 sesquiterpene synthase genes were identifi ed as type TPS-a in a phylogenetic analysis.The expression patterns for eight of the sesquiterpene synthase genes after treatment with various hormones or hydrogen peroxide were analyzed by real-time quantitative PCR.The results suggest that 100μM methyl jasmonate,ethephon,(±)-abscisic acid or hydrogen peroxide could be eff ective short-term eff ectors to increase the expression of sesquiterpene synthase genes,while 1 mM methyl salicylate may have long-term eff ects on increasing the expression of specifi c sesquiterpene synthase genes(e.g.,As-SesTPS,AsVS,AsTPS12 and AsTPS29).The expression changes in these genes under various conditions refl ected their specifi c roles during abiotic or biotic stresses.Heterologous expression of a novel A.sinensis sesquiterpene synthase gene,AsTPS2,in Escherichia coli produced a major humulene product,so AsTPS2 is renamed AsHS1.AsHS1 is diff erent from ASS1,AsSesTPS,and AsVS,for mainly producingα-humulene.Based on the predicted space conformation of the AsHS1 model,the small ligand molecule may bind to the free amino acid by hydrogen bonding for the catalytic function of the enzyme,while the substrate farnesyl diphosphate(FPP)probably binds to the free amino acid on one side of the RxR motif.Arg450,Asp453,Asp454,Thr457,and Glu461 from the NSE/DTE motif and D307 and D311 from the DDxxD motif were found to form a polar interaction with two Mg^(2+)clusters by docking.The Mg^(2+)-bound DDxxD and NSE/DTE motifs and the free RXR motif are jointly directed into the catalytic pocket of AsHS1.Comparison of the tertiary structural models of AsHS1 with ASS1 showed that they diff ered in structures in several positions,such as surrounding the secondary catalytic pocket,which may lead to diff erences in catalytic products.Based on the results,biosynthetic pathways for specifi c sesquiterpenes such asα-humulene in A.sinensis are proposed.This study provides novel insights into the functions of the sesquiterpene synthases of A.sinensis and enriches knowledge on agarwood formation.展开更多
Objective:To determine the genetic diversity,natural selection and mutations in Plasmodium(P.)knowlesi drug resistant molecular markers Kelch 13 and dhps gene in clinical samples of Malaysia.Methods:P.knowlesi full-le...Objective:To determine the genetic diversity,natural selection and mutations in Plasmodium(P.)knowlesi drug resistant molecular markers Kelch 13 and dhps gene in clinical samples of Malaysia.Methods:P.knowlesi full-length gene sequences Kelch 13 gene(PkK13)from 40 samples and dhps gene from 30 samples originating from Malaysian Borneo were retrieved from public databases.Genetic diversity,natural selection,and phylogenetic analysis of gene sequences were analysed using DNAsp v5.10 and MEGA v5.2.Results:Seventy-two single nucleotide polymorphic sites(SNPs)across the full-length PkK13 gene(63 synonymous substitutions and 9 non-synonymous substitutions)with nucleotide diversity ofπ~0.005 was observed.Analysis of the full-length Pkdhps gene revealed 73 SNPs andπ~0.006(44 synonymous substitutions and 29 non-synonymous substitutions).A high number of haplotypes(PkK13;H=37 and Pkdhps;H=29)with haplotype diversity of Hd~0.99 were found in both genes,indicating population expansion.Nine mutant alleles were identified in PkK13 amino acid alignment of which,7(Asp3Glu,Lys50Gln,Lys53Glu,Ser123Thr,Ser127Pro,Ser149Thr and Ala169Thr)were within the Plasmodium specific domain,2(Val372Ile and Lys424Asn)were in the BTB/POZ domain and no mutation was observed within the kelch propeller domain.The 29 non-synonymous mutations in the Pkdhps gene were novel and only presented in exon 1 and 2.Conclusions:Monitoring the mutations from clinical samples collected from all states of Malaysia along with clinical efficacy studies will be necessary to determine the drug resistance in P.knowlesi.展开更多
Background Herbicide tolerance in crops enables them to survive when lethal doses of herbicides are applied to surrounding weeds.Herbicide-tolerant crops can be developed through transgenic approaches or traditional m...Background Herbicide tolerance in crops enables them to survive when lethal doses of herbicides are applied to surrounding weeds.Herbicide-tolerant crops can be developed through transgenic approaches or traditional mutagenesis approaches.At present,no transgenic herbicide tolerant cotton have been commercialized in China due to the genetically-modified organism(GMO)regulation law.We aim to develop a non-transgenic herbicide-tolerant cotton through ethyl methanesulfonate(EMS)mutagenesis,offering an alternative choice for weed management.Results Seeds of an elite cotton cultivar Lumianyan 37(Lu37)were treated with EMS,and a mutant Lu37-1 showed strong tolerance to imidazolinone(IMI)herbicides was identified.A novel nonsynonymous substitution mutation Ser642Asn at acetolactate synthase(ALS)(Gh_D10G1253)in Lu37-1 mutant line was found to be the potential cause to the IMI herbicides tolerance in cotton.The Ser642Asn mutation in ALS did not present among the genomes of natural Gossypium species.Cleaved amplified polymorphic sequence(CAPS)markers were developed to identify the ALS mutant allele.The Arabidopsis overexpressing the mutanted ALS also showed high tolerance to IMI herbicides.Conclusion The nonsynonymous substitution mutation Ser642Asn of the ALS gene Gh_D10G1253 is a novel identi-fied mutation in cotton.This substitution mutation has also been identified in the orthologous ALS genes in other crops.This mutant ALS allele can be used to develop IMI herbicide-tolerant crops via a non-transgenic or transgenic approach.展开更多
Neuronal nitric oxide synthase(nNOS)was the producer of nitric oxide(NO)which played important gas messenger molecules in biological process.It also can take effect as immune regulation molecule in organism.Black rock...Neuronal nitric oxide synthase(nNOS)was the producer of nitric oxide(NO)which played important gas messenger molecules in biological process.It also can take effect as immune regulation molecule in organism.Black rockfish(Sebastes schlegelii)is an important economic fish which were widely farmed in East Asia countries.Meanwhile,the pathogenic bacteria such as the Edwardsiella tarda and Vibrio anguillarum in seawater always brought serious obstacles to their healthy growth.In order to explore the expression pattern of n NOS gene under the pathogen stimulation and predict its immune function,the n NOS gene in black rockfish named Ssn NOS was identified.It was 3780 bp in length,located on chromosome 6,and contained 27 coding domain sequence(CDs).According to the phylogenetic analysis,the Ssn NOS showed closest relative to the counterpart gene of swamp eel(Monopterus albus).Meanwhile,analysis of Ssn NOS expression in various healthy tissues showed that Ssn NOS expression level was highest in healthy brain tissues,followed by intestinal tissues.In addition,Ssn NOS showed significant expression changes in response to stimulation by two pathogens.Particular in gill,the expression of Ssn NOS after pathogenic stimulation increased significantly.The Elisa analysis showed the Ssn NOS content in gills was much higher than that in other tissues at all time points.Moreover,the expression patterns of Ssn NOS in brain,intestine and kidney after stimulation by pathogens showed a distinct expression pattern which first down-regulated and then up-regulated.Therefore,the Ssn NOS may be an important signaling molecule for fish to respond rapidly in immune stimulation.展开更多
Alzheimer’s disease (AD) is the most prevalent cause of dementia worldwide. Because of the progressive neurodegeneration, individual cognitive and behavioral functions are impaired, affecting the quality of life of m...Alzheimer’s disease (AD) is the most prevalent cause of dementia worldwide. Because of the progressive neurodegeneration, individual cognitive and behavioral functions are impaired, affecting the quality of life of millions of people. Although the exact pathogenesis of AD has not been fully elucidated, amyloid plaques, neurofibrillary tangles (NFTs), and sustaining neuroinflammation dominate its characteristics. As one of the major tau kinases leading to hyperphosphorylation and aggregation of tau, glycogen synthase kinase-3β (GSK-3β) has been drawing great attention in various AD studies. Another research focus of AD in recent years is the inflammasome, a multiprotein complex acting as a regulator in immunological reactions to exogenous and endogenous danger signals, of which the Nod-like receptor (NLR) family, pyrin domain-containing 3 (NLRP3) inflammasome has been studied mostly in AD and proven to play a significant role in AD development by its activation and downstream effects such as caspase-1 maturation and interleukin (IL)-1β release. Studies have shown that the NLRP3 inflammasome is activated in a GSK-3β-dependent way and that inhibition of the NLRP3 inflammasome downregulates GSK-3β, suggesting that these two important proteins are closely related. This article reviews the respective roles of GSK-3β and the NLRP3 inflammasome in AD as well as their relationship and interaction.展开更多
Callose contributes to many biological processes of higher plants including pollen development,cell plate and vascular tissue formation,as well as regulating the transport function of plasmodesmata.The functions of ca...Callose contributes to many biological processes of higher plants including pollen development,cell plate and vascular tissue formation,as well as regulating the transport function of plasmodesmata.The functions of callose synthase genes in maize have been little studied.We describe a maize male-sterile mutant 39(ms39)characterized by reduced plant height.In this study,we confirmed using CRISPR/Cas9 technology that a mutation in Zm00001d043909(ZmCals12),encoding a callose synthase,is responsible for the male sterility of the ms39 mutant.Compared with male-fertile plants,callose deposition around the dyads and tetrads in ms39 anthers was significantly reduced.Increased cell autophagy observed in ms39 anthers may have been due to the premature programmed cell death of tapetal cells,leading to collapse of the anther wall structure.Disordered glucose metabolism in ms39 may have intensified autophagy in anthers.Evaluation of the ms39 gene on maize heterosis by paired-crossed experiment with 11 maize inbred lines indicated that ms39 can be used for maize hybrid seed production.展开更多
BACKGROUND Oxaliplatin(Oxa)is the first-line chemotherapy drug for colorectal cancer(CRC),and Oxa resistance is crucial for treatment failure.Prostaglandin F_(2α)synthase(PGF 2α)(PGFS),an enzyme that catalyzes the p...BACKGROUND Oxaliplatin(Oxa)is the first-line chemotherapy drug for colorectal cancer(CRC),and Oxa resistance is crucial for treatment failure.Prostaglandin F_(2α)synthase(PGF 2α)(PGFS),an enzyme that catalyzes the production of PGF_(2α),is involved in the proliferation and growth of a variety of tumors.However,the role of PGFS in Oxa resistance in CRC remains unclear.AIM To explore the role and related mechanisms of PGFS in mediating Oxa resistance in CRC.METHODS The PGFS expression level was examined in 37 pairs of CRC tissues and paracancerous tissues at both the mRNA and protein levels.Overexpression or knockdown of PGFS was performed in CRC cell lines with acquired Oxa resistance(HCT116-OxR and HCT8-OxR)and their parental cell lines(HCT116 and HCT8)to assess its influence on cell proliferation,chemoresistance,apoptosis,and DNA damage.For determination of the underlying mechanisms,CRC cells were examined for platinum-DNA adducts and reactive oxygen species(ROS)levels in the presence of a PGFS inhibitor or its products.RESULTS Both the protein and mRNA levels of PGFS were increased in the 37 examined CRC tissues compared to the adjacent normal tissues.Oxa induced PGFS expression in the parental HCT116 and HCT8 cells in a dosedependent manner.Furthermore,overexpression of PGFS in parental CRC cells significantly attenuated Oxainduced proliferative suppression,apoptosis,and DNA damage.In contrast,knockdown of PGFS in Oxa-resistant HCT116 and HCT8 cells(HCT116-OxR and HCT8-OxR)accentuated the effect of Oxa treatment in vitro and in vivo.The addition of the PGFS inhibitor indomethacin enhanced the cytotoxicity caused by Oxa.Treatment with the PGFS-catalyzed product PGF_(2α)reversed the effect of PGFS knockdown on Oxa sensitivity.Interestingly,PGFS inhibited the formation of platinum-DNA adducts in a PGF_(2α)-independent manner.PGF_(2α)exerts its protective effect against DNA damage by reducing ROS levels.CONCLUSION PGFS promotes resistance to Oxa in CRC via both PGF_(2α)-dependent and PGF_(2α)-independent mechanisms.展开更多
BACKGROUND Clinical prognosis often worsens due to high recurrence rates following radical surgery for colon cancer.The examination of high-risk recurrence factors post-surgery provides critical insights for disease e...BACKGROUND Clinical prognosis often worsens due to high recurrence rates following radical surgery for colon cancer.The examination of high-risk recurrence factors post-surgery provides critical insights for disease evaluation and treatment planning.AIM To explore the relationship between metastasis-associated factor-1 in colon cancer(MACC1)and vacuolar ATP synthase(V-ATPase)expression in colon cancer tissues,and recurrence rate in patients undergoing radical colon cancer surgery.METHODS We selected 104 patients treated with radical colon cancer surgery at our hospital from January 2018 to June 2021.Immunohistochemical staining was utilized to assess the expression levels of MACC1 and V-ATPase in these patients.RESULTS The rates of MACC1 and V-ATPase positivity were 64.42%and 67.31%,respe-ctively,in colon cancer tissues,which were significantly higher than in paracan-cerous tissues(P<0.05).Among patients with TNM stage III,medium to low differentiation,and lymph node metastasis,the positive rates of MACC1 and V-ATPase were significantly elevated in comparison to patients with TNM stage I-II,high differentiation,and no lymph node metastasis(P<0.05).The rate of MACC1 positivity was 76.67%in patients with tumor diameters>5 cm,notably higher than in patients with tumor diameters≤5 cm(P<0.05).We observed a positive correlation between MACC1 and V-ATPase expression(rs=0.797,P<0.05).The positive rates of MACC1 and V-ATPase were significantly higher in patients with recurrence compared to those without(P<0.05).Logistic regression analysis revealed TNM stage,lymph node metastasis,MACC1 expression,and V-ATPase expression as risk factors for postoperative colon cancer recurrence(OR=6.322,3.435,2.683,and 2.421;P<0.05).CONCLUSION The upregulated expression of MACC1 and V-ATPase in colon cancer patients appears to correlate with clinicopathological features and post-radical surgery recurrence.展开更多
BACKGROUND: At present, inhalation of nitrogen monoxidum (NO) or other angiotenic is widely used to cure hypoxic pulmonary artery hypertension. In addition, recent researches demonstrate that postganglionic fiber o...BACKGROUND: At present, inhalation of nitrogen monoxidum (NO) or other angiotenic is widely used to cure hypoxic pulmonary artery hypertension. In addition, recent researches demonstrate that postganglionic fiber of stellate ganglion can regulate contents of blood vessel endothelium-calcitonin gene-related peptide (BVE-CGRP) and nitricoxide synthase (NOS) in lung tissue. Therefore, stellate ganglion which is blocked with the local anesthetic may cause therapeutic effects on hypoxic pulmonary artery hypertension. OBJECTIVE: To observe the effects of stellate block on calcitonin gene-related peptide (CGRP) of vasodilation factors, prostacyclin, endothelin-i of vasoconstriction factors, thromboxan, blood vessel endothelium-nitricoxide synthase (BVE-NOS) and mean arterial pressure of lung tissue in rabbits with hypoxic pulmonary artery hypertension. DESIGN: Randomly controlled animal study. SETTING: Neurological Institute of Taihe Hospital Affiliated to Yunyang Medical College. MATERIALS: A total of 24 adult Japanese rabbits of both genders and weighing 2.3 - 2.6 kg were provided by Animal Experimental Center of Hubei Academy of Medical Science. SP kit was provided by Beijing Zhongshan Biotechnology Co., Ltd.; moreover, kits of endothelin-1, CGRP, prostacyclin and thromboxan were provided by Radioimmunity Institute, Scientific and Technological Developing Center, General Hospital of Chinese PLA, and color image analytical system (Leica-Q500IW) was made in Germany. METHODS:The experiment was carried out in the Neurological Institute of Taihe Hospital affiliated to Yunyang Medical College from February to December 2002. ① Rabbits were performed with aseptic manipulation to exposure left stellate ganglion and then it was put in epidural catheter for 1 week. In addition, one end of epidural catheter was fixed near by stellate ganglion and the other end was fixed through dorsal neck. All rabbits were randomly divided into 4 groups, including normal control group, stellate block group, hypoxia group and hypoxia + stellate block group, with 6 in each group. Rabbits in the normal control group were perfused with saline through epidural catheter with 0.5 mL once for three times per day and 3 successive days in total; in addition, rabbits in the stellate block group were perfused with 2.5 g/L bupivacaine through epidural catheter with 0.5 mL once for three times per day and 3 successive days in total. Rabbits in the hypoxia group were used to establish hypoxic pulmonary artery hypertension models. That was to say, the experimental rabbits were put in hypoxic box (containing sodalime and calcium chloride to absorb CO2 and water) and given various flows of oxygen and nitrogen through the two lateral wells simultaneously. And then, oxygen was monitored with oxygen-concentration monitoring device to control the concentration in (10±2)% for 8 hours per day and 2 successive weeks in total. Rabbits in the hypoxia + stellate block group were used to establish hypoxia models as the same as those in the hypoxia group. Two weeks later, 2.5 g,/L bupivacaine was pushed into epidural catheter with 0.5 mL once for three times per day and 3 successive days in total. Breast was directly opened to measure mean pulmonary artery pressure.② 6 mL blood was collected through pulmonary arterial duct to measure levels of plasma CGRP, prostacyclin, endothelin-I and thromboxane with radio-immunity technique; meanwhile, immunohistochemical staining was used to observe the changes of BVE-NOS content of the experimental rabbits in all groups. MAIN OUTCOME MEASURES: Changes of CGRP, prostacyclin, endothelin-1 and thromboxane and BVE-NOS. RESULTS: A total of 24 experimental rabbits were involved in the final analysis. ①As compared with those in the normal control group, hypoxic pulmonary artery hypertension of the experimental rabbits was higher in the hypoxia group and hypoxia + stellate block group after hypoxia [(3.8±0.30), (3.16±0.45), (2.60± 0.27) kPa, P 〈 0.05, 0.01]; CGRP was lower [(68.20 ±8.78), (108.24 ±14.35), (130.25 ±22.70) ng/L, P 〈 0.05, 0.01]; prostacyclin was lower [(94.45± 10.68), (98.77± 12.31), (155.27±20.67) ng/L, P 〈 0.01]; endothelin-1 was higher [(184.7±29.66), (115.27± 13.62), (98.20±11.52), ng/L, P 〈 0.05, 0.01]; thromboxan was higher [(226.27 ±30.46), (207.67 ±27.32), (124.25 ± 16.89) ng/L, P 〈 0.01 ]. As compared with that in hypoxia group, hypoxic pulmonary artery hypertension was decreased in hypoxia + stellate block group (P 〈 0.05), CGRP was increased (P 〈 0.01), and endothelin-1 was decreased remarkably (P 〈 0.05). ② Level of BVE-NOS of the experimental rabbits was higher in stellate block group, hypoxia group and hypoxia + stellate block group than that in the normal control group [(0.25±0.06), (0.27±0.07), (0.46± 0.12), (0.14±0.03), P 〈 0.05], and NOS level was higher in the hypoxia + stellate block group than that in hypoxia group (P 〈 0.05). CONCLUSION: Mean arterial pressure is decreased in rabbits with hypoxic pulmonary artery hypertension after stellate block and level of endothelin-1 is also decreased; however, levels of CGRP and NOS are increased respectively.展开更多
<abstract>Aim: To investigate the effect of aging on the expression of nitric oxide synthase I (NOS I) and the activity of NOS in rat penis. Methods: Sixty male rats from 3 age groups (adult, old and senescent) ...<abstract>Aim: To investigate the effect of aging on the expression of nitric oxide synthase I (NOS I) and the activity of NOS in rat penis. Methods: Sixty male rats from 3 age groups (adult, old and senescent) were investigated. The expression of NOS I protein and mRNA in rat penis were detected by Western blot and RT-PCR respectively and the NOS activity, with ultraviolet spectrophotometry. Results: In the old and senescent group, NOS I protein expression was significantly decreased as compared with the adult. NOS I mRNA expression was well correlated with the protein expression. NOS activity was not statistically different between the adult and old groups, but it was significantly reduced in the senescent compared with the adult group (P<0.01). Conclusion: The aging-induced decreases in NOS I expression and NOS activity may be one of the main mechanisms leading to erectile dysfunction in the senescent rats.展开更多
Aim: To investigate the effect of cavernous nerve injury on the nNOS-containing nerve fibers in rat corpus cavernosum.Methods: Thirty-three male SD rats were randomized into 3 groups: 5 rats underwent pelvic explorati...Aim: To investigate the effect of cavernous nerve injury on the nNOS-containing nerve fibers in rat corpus cavernosum.Methods: Thirty-three male SD rats were randomized into 3 groups: 5 rats underwent pelvic exploration without tran-section of cavernous nerve as the sham-operated controls, the unilateral injury group (14 rats) had the cavernous nerve cuton one side, and the bilateral injury group (14 rats) had the nerves cut on both sides. Corpora cavernosa were harvestedat the 3rd week and 6th month after surgery, nNOS-positive nerve fibers were examined with strepavidin peroxidase im-munohistochemistry techniques (SP method). Results: After bilateral ablation, the nNOS-positive nerve fibers weresignificantly decreased at both the 3rd week ( 17 ± 4) and the 6th month (16 ± 4). For the unilateral injury group, thenNOS-positive nerve fibers were similarly decreased on the side of the neurotomy at the 3rd week (18 ± 6), but by the 6thmonth, the number increased significantly (61±9) and approximated the level on the contralateral side (81 ± 13). Con-clusion: In rats after unilateral cavernous nerve ablation, nNOS-containing nerve fibers might regenerate 6 months afteroperation, but regeneration did not occur in animals with bilateral cavernous nerve injury. Results suggest that duringpelvic radical surgery, the cavernous nerve should be preserved at least on one side in order to accomplish adequate regen-eration. (Asian J Androl 1999 Sep ; 1: 135 - 138)展开更多
BACKGROUND: Abnormal changes in magnesium ion are closely related to cerebral injury. At present, some evidence indicates that magnesium reagent can improve nerve function and prognosis of patients with cerebral inju...BACKGROUND: Abnormal changes in magnesium ion are closely related to cerebral injury. At present, some evidence indicates that magnesium reagent can improve nerve function and prognosis of patients with cerebral injury. OBJECTIVE: To observe the effect of magnesium sulfate on changes in nitric oxide synthase (NOS) activity in brain tissue of rats with acute craniocerebral injury. DESIGN: Completely randomized grouping design and randomly controlled study. SETTING: Laboratory of Neurosurgery, the Third Hospital of Chinese PLA. MATERIALS: Fifty-four male SD rats of clean grade and weighing 220 - 250 g were randomly divided into normal control group (n =6), cerebral injury group (n =24) and magnesium sulfate group (n =24). Especially, rats in cerebral injury group and magnesium sulfate group were equally divided into four subgroups and observed at 0.5, 2, 6 and 24 hours after model establishment. A solution of 125 g/L of magnesium sulfate was provided by the Seventh Pharmaceutical Factory of Wuxi and the NOS assay kit by Nanjing Jiancheng Bioengineering Institute. METHODS: The experiment was carried out in the Institute of Neurosurgery, the Third Hospital of Chinese PLA from August 2000 to August 2002. ① Rats in the cerebral injury group and magnesium sulfate group were anesthetized to establish cerebral injury models based on modified Feeney technique; magnesium sulfate group were intraperitoneally injected 600 mg/kg magnesium sulfate (125 g/L), but rats in the normal control group remained untreated. ② At 0.5, 2, 6 and 24 hours after cerebral injury, rats in cerebral injury group and magnesium sulfate group were decapitated and brains were dissected. Cerebral cortex of rats in cerebral injury group was selected for NOS assay; in addition, at 0.5 hour after cerebral injury, a portion of the parietal lobe was selected from the brains of rats in the normal control group. Brain samples were homogenized, the homogenated centrifuged and the supernatants were used to measure NOS activity with NOS kit. ③ Differences among the three groups were compared with t test. MAIN OUTCOME MEASURES: NOS activity in cerebral cortex of rats in each group. RESULTS: A total of 54 SD rats were involved in the final analysis. At 0.5 hour after cerebral injury, NOS activity in cerebral cortex was (42.45 ± 13.46) nmol/L in cerebral injury group and (41.17 ± 12.53) nmol/L in magnesium sulfate group, respectively, which was higher than that in normal control group [(39.45 ± 11.84) nmol/L, P 〈 0.05]. At 2 hours after cerebral injury, NOS activities were (66.48 ±21.43) and (63.24 ± 19.18) umol/L, respectively, while at 6 hours after cerebral injury, NOS activities were (62.45 ± 24.18) and (51.97 ±20.46) nmol/L, respectively, which were higher than those in normal control group (P 〈 0.0 1). At 24 hours after cerebral injury, NOS activity returned to basal level. Moreover, NOS activity was significantly lower in the magnesium sulfate group than that in the cerebral injury group at 2 and 6 hours after cerebral injury (P 〈 0.05, 0.01).CONCLUSION: NOS activity is increased in injured brain tissue of rats with craniocerebral injury, and treatment with magnesium sulfate provides some degrees of protection possibly through inhibition of NOS activity after cerebral injury.展开更多
基金funded by the National Natural Science Foundation of China(31972281)。
文摘Cyperus difformis L.is a troublesome weed in paddy fields and has attracted attention due to its resistance to acetohydroxyacid synthase(AHAS)inhibitors.It was found that the amino acid mutation in AHAS was the primary cause for the resistance of Cyperus difformis.However,the effect of different mutations on AHAS function is not clear in Cyperus difformis.To confirm the effect of mutations on AHAS function,six biotypes were collected,including Pro197Arg,Pro197Ser,Pro197Leu,Asp376Glu,Trp574Leu and wild type,from Hunan,Anhui,Jiangxi and Jiangsu provinces,China and the function of AHAS was characterized.The AHAS in vitro inhibition assay results indicated that the mutations decreased the sensitivity of AHAS to pyrazosulfuron-ethyl,in which the I_(50)(the half maximal inhibitory concentration)of wild type AHAS was 0.04μmol L^(-1)and Asp376Glu,Pro197Leu,Pro197Arg,Pro197Ser and Trp574Leu mutations were 3.98,11.50,40.38,38.19 and 311.43μmol L^(-1),respectively.In the determination of enzyme kinetics parameters,the Km and the maximum reaction velocity(Vmax)of the wild type were 5.18 mmol L^(-1)and 0.12 nmol mg^(-1)min^(-1),respectively,and the Km values of AHAS with Asp376Glu,Trp574Leu,Pro197Leu and Pro197Ser mutations were 0.38-0.93 times of the wild type.The Km value of the Pro197Arg mutation was 1.14times of the wild type,and the Vmax values of the five mutations were 1.17-3.33-fold compared to the wild type.It was found that the mutations increased the affinity of AHAS to the substrate,except for the Pro197Arg mutation.At a concentration of 0.0032-100 mmol L^(-1)branched-chain amino acids(BCAAs),the sensitivity of the other four mutant AHAS biotypes to feedback inhibition decreased,except for the Pro197Arg mutation.This study elucidated the effect of different mutations on AHAS function in Cyperus difformis and provided ideas for further study of resistance development.
基金supported by the National Key Research and Development Program of China(2022YFD1200700)the Nuclear Energy Development Research Program of the State Administration of Science,Technology,and Industry for National Defense(Crop Varietal Improvement and Insect Pests Control by Nuclear Radiation)the China Agriculture Research System of MOF and MARA(CARS-03)。
文摘Lesion mimic often exhibits leaf disease-like symptoms even in the absence of pathogen infection,and is characterized by a hypersensitive-response(HR)that closely linked to plant disease resistance.Despite this,only a few lesion mimic genes have been identified in wheat.In this investigation,a lesion mimic wheat mutant named je0297 was discovered,showing no alteration in yield components when compared to the wild type(WT).Segregation ratio analysis of the F_(2)individuals resulting from the cross between the WT and the mutant revealed that the lesion mimic was governed by a single recessive gene in je0297.Using Bulked segregant analysis(BSA)and exome capture sequencing,we mapped the lesion mimic gene designated as lm6 to chromosome 6BL.Further gene fine mapping using 3315 F_(2)individuals delimited the lm6 within a 1.18 Mb region.Within this region,we identified 16 high-confidence genes,with only two displaying mutations in je0297.Notably,one of the two genes,responsible for encoding flavonol synthase,exhibited altered expression levels.Subsequent phenotype analysis of TILLING mutants confirmed that the gene encoding flavonol synthase was indeed the causal gene for lm6.Transcriptome sequencing analysis revealed that the DEGs between the WT and mutant were significantly enriched in KEGG pathways related to flavonoid biosynthesis,including flavone and flavonol biosynthesis,isoflavonoid biosynthesis,and flavonoid biosynthesis pathways.Furthermore,more than 30 pathogen infection-related(PR)genes exhibited upregulation in the mutant.Corresponding to this expression pattern,the flavonoid content in je0297 showed a significant decrease in the 4^(th)leaf,accompanied by a notable accumulation of reactive oxygen,which likely contributed to the development of lesion mimic in the mutant.This investigation enhances our comprehension of cell death signaling pathways and provides a valuable gene resource for the breeding of disease-resistant wheat.
基金supported by the National Natural Science Foundation of China (32172521)the Excellent Youth Science Foundation of Heilongjiang Province,China (YQ2023C006)+1 种基金the Talent Introduction Program of Northeast Agricultural University of Chinathe Collaborative Innovation System of the Agricultural Bio-economy in Heilongjiang Province,China
文摘Sucrose phosphate synthase(SPS)is a rate-limiting enzyme that works in conjunction with sucrose-6-phosphate phosphatase(SPP)for sucrose synthesis,and it plays an essential role in energy provisioning during growth and development in plants as well as improving fruit quality.However,studies on the systematic analysis and evolutionary pattern of the SPS gene family in apple are still lacking.In the present study,a total of seven MdSPS and four MdSPP genes were identified from the Malus domestica genome GDDH13 v1.1.The gene structures and their promoter cis-elements,protein conserved motifs,subcellular localizations,physiological functions and biochemical properties were analyzed.A chromosomal location and gene-duplication analysis demonstrated that whole-genome duplication(WGD)and segmental duplication played vital roles in MdSPS gene family expansion.The Ka/Ks ratio of pairwise MdSPS genes indicated that the members of this family have undergone strong purifying selection during domestication.Furthermore,three SPS gene subfamilies were classified based on phylogenetic relationships,and old gene duplications and significantly divergent evolutionary rates were observed among the SPS gene subfamilies.In addition,a major gene related to sucrose accumulation(MdSPSA2.3)was identified according to the highly consistent trends in the changes of its expression in four apple varieties(‘Golden Delicious’,‘Fuji’,‘Qinguan’and‘Honeycrisp’)and the correlation between gene expression and soluble sugar content during fruit development.Furthermore,the virus-induced silencing of MdSPSA2.3 confirmed its function in sucrose accumulation in apple fruit.The present study lays a theoretical foundation for better clarifying the biological functions of the MdSPS genes during apple fruit development.
基金supported by the Natural Nature Science Foundation of China,Nos.82030071,81874004the Science and Technology Major Project of Changsha,No.kh2103008(all to JZH).
文摘Treatment with metformin can lead to the recovery of pleiotropic biological activities after spinal cord injury.However,its effect on spinal cord injury in aged mice remains unclear.Considering the essential role of angiogenesis during the regeneration process,we hypothesized that metformin activates the adenosine monophosphate-activated protein kinase/endothelial nitric oxide synthase pathway in endothelial cells,thereby promoting microvascular regeneration in aged mice after spinal cord injury.In this study,we established young and aged mouse models of contusive spinal cord injury using a modified Allen method.We found that aging hindered the recovery of neurological function and the formation of blood vessels in the spinal cord.Treatment with metformin promoted spinal cord microvascular endothelial cell migration and blood vessel formation in vitro.Furthermore,intraperitoneal injection of metformin in an in vivo model promoted endothelial cell proliferation and increased the density of new blood vessels in the spinal cord,thereby improving neurological function.The role of metformin was reversed by compound C,an adenosine monophosphate-activated protein kinase inhibitor,both in vivo and in vitro,suggesting that the adenosine monophosphate-activated protein kinase/endothelial nitric oxide synthase pathway likely regulates metformin-mediated angiogenesis after spinal cord injury.These findings suggest that metformin promotes vascular regeneration in the injured spinal cord by activating the adenosine monophosphate-activated protein kinase/endothelial nitric oxide synthase pathway,thereby improving the neurological function of aged mice after spinal cord injury.
基金supported by the Natural Science Foundation of ChinaNos.81971212 (to FG)+7 种基金81601129 (to XXX)the Open Fund of the Key Laboratory of Medical ElectrophysiologyMinistry of Education&Medical Electrophysiological Key Laboratory of Sichuan ProvinceInstitute of Cardiovascular ResearchSouthwest Medical UniversityNo.KeyME-2018-07 (to FG)Liaoning Province Xingliao Talent Program ProjectNo.XLYC1907164 (to FG)
文摘Dysfunction of neuronal nitric oxide synthase contributes to neurotoxicity,which triggers cell death in various neuropathological diseases,including epilepsy.Studies have shown that inhibition of neuronal nitric oxide synthase activity increases the epilepsy threshold,that is,has an anticonvulsant effect.However,the exact role and potential mechanism of neuronal nitric oxide synthase in seizures are still unclear.In this study,we performed RNA sequencing,functional enrichment analysis,and weighted gene coexpression network analysis of the hippocampus of tremor rats,a rat model of genetic epilepsy.We found damaged hippocampal mitochondria and abnormal succinate dehydrogenase level and Na+-K+-ATPase activity.In addition,we used a pilocarpine-induced N2a cell model to mimic epileptic injury.After application of neuronal nitric oxide synthase inhibitor 7-nitroindazole,changes in malondialdehyde,lactate dehydrogenase and superoxide dismutase,which are associated with oxidative stress,were reversed,and the increase in reactive oxygen species level was reversed by 7-nitroindazole or reactive oxygen species inhibitor N-acetylcysteine.Application of 7-nitroindazole or N-acetylcysteine downregulated the expression of caspase-3 and cytochrome c and reversed the apoptosis of epileptic cells.Furthermore,7-nitroindazole or N-acetylcysteine downregulated the abnormally high expression of NLRP3,gasdermin-D,interleukin-1βand interleukin-18.This indicated that 7-nitroindazole and N-acetylcysteine each reversed epileptic cell death.Taken together,our findings suggest that the neuronal nitric oxide synthase/reactive oxygen species pathway is involved in pyroptosis of epileptic cells,and inhibiting neuronal nitric oxide synthase activity or its induced oxidative stress may play a neuroprotective role in epilepsy.
基金supported by the National Natural Science Foundation of China(81773844).
文摘Sesquiterpenes are the major pharmacodynamic components of agarwood,a precious traditional Chinese medicine obtained from the resinous portions of Aquilaria sinensis trees that form in response to environmental stressors.To characterize the sesquiterpene synthases responsible for sesquiterpene production in A.sinensis,a bioinformatics analysis of the genome of A.sinensis identifi ed six new terpene synthase genes,and 16 sesquiterpene synthase genes were identifi ed as type TPS-a in a phylogenetic analysis.The expression patterns for eight of the sesquiterpene synthase genes after treatment with various hormones or hydrogen peroxide were analyzed by real-time quantitative PCR.The results suggest that 100μM methyl jasmonate,ethephon,(±)-abscisic acid or hydrogen peroxide could be eff ective short-term eff ectors to increase the expression of sesquiterpene synthase genes,while 1 mM methyl salicylate may have long-term eff ects on increasing the expression of specifi c sesquiterpene synthase genes(e.g.,As-SesTPS,AsVS,AsTPS12 and AsTPS29).The expression changes in these genes under various conditions refl ected their specifi c roles during abiotic or biotic stresses.Heterologous expression of a novel A.sinensis sesquiterpene synthase gene,AsTPS2,in Escherichia coli produced a major humulene product,so AsTPS2 is renamed AsHS1.AsHS1 is diff erent from ASS1,AsSesTPS,and AsVS,for mainly producingα-humulene.Based on the predicted space conformation of the AsHS1 model,the small ligand molecule may bind to the free amino acid by hydrogen bonding for the catalytic function of the enzyme,while the substrate farnesyl diphosphate(FPP)probably binds to the free amino acid on one side of the RxR motif.Arg450,Asp453,Asp454,Thr457,and Glu461 from the NSE/DTE motif and D307 and D311 from the DDxxD motif were found to form a polar interaction with two Mg^(2+)clusters by docking.The Mg^(2+)-bound DDxxD and NSE/DTE motifs and the free RXR motif are jointly directed into the catalytic pocket of AsHS1.Comparison of the tertiary structural models of AsHS1 with ASS1 showed that they diff ered in structures in several positions,such as surrounding the secondary catalytic pocket,which may lead to diff erences in catalytic products.Based on the results,biosynthetic pathways for specifi c sesquiterpenes such asα-humulene in A.sinensis are proposed.This study provides novel insights into the functions of the sesquiterpene synthases of A.sinensis and enriches knowledge on agarwood formation.
基金supported by the institutional funding committee of Najran University,Najran,Saudi Arabia(Project code:NU/IFC/ENT/01/007).
文摘Objective:To determine the genetic diversity,natural selection and mutations in Plasmodium(P.)knowlesi drug resistant molecular markers Kelch 13 and dhps gene in clinical samples of Malaysia.Methods:P.knowlesi full-length gene sequences Kelch 13 gene(PkK13)from 40 samples and dhps gene from 30 samples originating from Malaysian Borneo were retrieved from public databases.Genetic diversity,natural selection,and phylogenetic analysis of gene sequences were analysed using DNAsp v5.10 and MEGA v5.2.Results:Seventy-two single nucleotide polymorphic sites(SNPs)across the full-length PkK13 gene(63 synonymous substitutions and 9 non-synonymous substitutions)with nucleotide diversity ofπ~0.005 was observed.Analysis of the full-length Pkdhps gene revealed 73 SNPs andπ~0.006(44 synonymous substitutions and 29 non-synonymous substitutions).A high number of haplotypes(PkK13;H=37 and Pkdhps;H=29)with haplotype diversity of Hd~0.99 were found in both genes,indicating population expansion.Nine mutant alleles were identified in PkK13 amino acid alignment of which,7(Asp3Glu,Lys50Gln,Lys53Glu,Ser123Thr,Ser127Pro,Ser149Thr and Ala169Thr)were within the Plasmodium specific domain,2(Val372Ile and Lys424Asn)were in the BTB/POZ domain and no mutation was observed within the kelch propeller domain.The 29 non-synonymous mutations in the Pkdhps gene were novel and only presented in exon 1 and 2.Conclusions:Monitoring the mutations from clinical samples collected from all states of Malaysia along with clinical efficacy studies will be necessary to determine the drug resistance in P.knowlesi.
基金This research was funded by the National Key Research and Development Program of China,grant number 2016YFD0101418the National Natural Science Foundation of China,grant number 32172047.
文摘Background Herbicide tolerance in crops enables them to survive when lethal doses of herbicides are applied to surrounding weeds.Herbicide-tolerant crops can be developed through transgenic approaches or traditional mutagenesis approaches.At present,no transgenic herbicide tolerant cotton have been commercialized in China due to the genetically-modified organism(GMO)regulation law.We aim to develop a non-transgenic herbicide-tolerant cotton through ethyl methanesulfonate(EMS)mutagenesis,offering an alternative choice for weed management.Results Seeds of an elite cotton cultivar Lumianyan 37(Lu37)were treated with EMS,and a mutant Lu37-1 showed strong tolerance to imidazolinone(IMI)herbicides was identified.A novel nonsynonymous substitution mutation Ser642Asn at acetolactate synthase(ALS)(Gh_D10G1253)in Lu37-1 mutant line was found to be the potential cause to the IMI herbicides tolerance in cotton.The Ser642Asn mutation in ALS did not present among the genomes of natural Gossypium species.Cleaved amplified polymorphic sequence(CAPS)markers were developed to identify the ALS mutant allele.The Arabidopsis overexpressing the mutanted ALS also showed high tolerance to IMI herbicides.Conclusion The nonsynonymous substitution mutation Ser642Asn of the ALS gene Gh_D10G1253 is a novel identi-fied mutation in cotton.This substitution mutation has also been identified in the orthologous ALS genes in other crops.This mutant ALS allele can be used to develop IMI herbicide-tolerant crops via a non-transgenic or transgenic approach.
基金supported by the Natural Science Foundation of Shandong Province(No.ZR2020QC214)the Young Experts of Taishan Scholars(No.tsqn201909130)+3 种基金the Science and Technology Support Plan for Youth Innovation of Colleges and Universities in Shandong Province(No.2019KJF003)the‘First Class Fishery Discipline’Programme in Shandong Provincea special talent programme‘One Thing One Decision(YishiYiyi)’Programme in Shandong Province,Chinathe Breeding Plan of Shandong Provincial Qingchuang Research Team(2019)。
文摘Neuronal nitric oxide synthase(nNOS)was the producer of nitric oxide(NO)which played important gas messenger molecules in biological process.It also can take effect as immune regulation molecule in organism.Black rockfish(Sebastes schlegelii)is an important economic fish which were widely farmed in East Asia countries.Meanwhile,the pathogenic bacteria such as the Edwardsiella tarda and Vibrio anguillarum in seawater always brought serious obstacles to their healthy growth.In order to explore the expression pattern of n NOS gene under the pathogen stimulation and predict its immune function,the n NOS gene in black rockfish named Ssn NOS was identified.It was 3780 bp in length,located on chromosome 6,and contained 27 coding domain sequence(CDs).According to the phylogenetic analysis,the Ssn NOS showed closest relative to the counterpart gene of swamp eel(Monopterus albus).Meanwhile,analysis of Ssn NOS expression in various healthy tissues showed that Ssn NOS expression level was highest in healthy brain tissues,followed by intestinal tissues.In addition,Ssn NOS showed significant expression changes in response to stimulation by two pathogens.Particular in gill,the expression of Ssn NOS after pathogenic stimulation increased significantly.The Elisa analysis showed the Ssn NOS content in gills was much higher than that in other tissues at all time points.Moreover,the expression patterns of Ssn NOS in brain,intestine and kidney after stimulation by pathogens showed a distinct expression pattern which first down-regulated and then up-regulated.Therefore,the Ssn NOS may be an important signaling molecule for fish to respond rapidly in immune stimulation.
基金supported by grants from the National Natural Science Foundation of China(No.92049107 and No.31929002)the Innovative Research Groups of the National Natural Science Foundation of China(No.81721005)the Academic Frontier Youth Team Project to Xiaochuan Wang from Huazhong University of Science and Technology.
文摘Alzheimer’s disease (AD) is the most prevalent cause of dementia worldwide. Because of the progressive neurodegeneration, individual cognitive and behavioral functions are impaired, affecting the quality of life of millions of people. Although the exact pathogenesis of AD has not been fully elucidated, amyloid plaques, neurofibrillary tangles (NFTs), and sustaining neuroinflammation dominate its characteristics. As one of the major tau kinases leading to hyperphosphorylation and aggregation of tau, glycogen synthase kinase-3β (GSK-3β) has been drawing great attention in various AD studies. Another research focus of AD in recent years is the inflammasome, a multiprotein complex acting as a regulator in immunological reactions to exogenous and endogenous danger signals, of which the Nod-like receptor (NLR) family, pyrin domain-containing 3 (NLRP3) inflammasome has been studied mostly in AD and proven to play a significant role in AD development by its activation and downstream effects such as caspase-1 maturation and interleukin (IL)-1β release. Studies have shown that the NLRP3 inflammasome is activated in a GSK-3β-dependent way and that inhibition of the NLRP3 inflammasome downregulates GSK-3β, suggesting that these two important proteins are closely related. This article reviews the respective roles of GSK-3β and the NLRP3 inflammasome in AD as well as their relationship and interaction.
基金supported by the National Natural Science Foundation of China(31771876)the Sichuan Province Science and Technology Program(2021YFYZ0011,2021YFYZ0017).
文摘Callose contributes to many biological processes of higher plants including pollen development,cell plate and vascular tissue formation,as well as regulating the transport function of plasmodesmata.The functions of callose synthase genes in maize have been little studied.We describe a maize male-sterile mutant 39(ms39)characterized by reduced plant height.In this study,we confirmed using CRISPR/Cas9 technology that a mutation in Zm00001d043909(ZmCals12),encoding a callose synthase,is responsible for the male sterility of the ms39 mutant.Compared with male-fertile plants,callose deposition around the dyads and tetrads in ms39 anthers was significantly reduced.Increased cell autophagy observed in ms39 anthers may have been due to the premature programmed cell death of tapetal cells,leading to collapse of the anther wall structure.Disordered glucose metabolism in ms39 may have intensified autophagy in anthers.Evaluation of the ms39 gene on maize heterosis by paired-crossed experiment with 11 maize inbred lines indicated that ms39 can be used for maize hybrid seed production.
基金the S and T Program of Hebei,No.22377704DMedical Science Research Project of Hebei Province,No.20190510Postgraduate’s Innovation Fund Project of Hebei Province,No.CXZZBS2021077.
文摘BACKGROUND Oxaliplatin(Oxa)is the first-line chemotherapy drug for colorectal cancer(CRC),and Oxa resistance is crucial for treatment failure.Prostaglandin F_(2α)synthase(PGF 2α)(PGFS),an enzyme that catalyzes the production of PGF_(2α),is involved in the proliferation and growth of a variety of tumors.However,the role of PGFS in Oxa resistance in CRC remains unclear.AIM To explore the role and related mechanisms of PGFS in mediating Oxa resistance in CRC.METHODS The PGFS expression level was examined in 37 pairs of CRC tissues and paracancerous tissues at both the mRNA and protein levels.Overexpression or knockdown of PGFS was performed in CRC cell lines with acquired Oxa resistance(HCT116-OxR and HCT8-OxR)and their parental cell lines(HCT116 and HCT8)to assess its influence on cell proliferation,chemoresistance,apoptosis,and DNA damage.For determination of the underlying mechanisms,CRC cells were examined for platinum-DNA adducts and reactive oxygen species(ROS)levels in the presence of a PGFS inhibitor or its products.RESULTS Both the protein and mRNA levels of PGFS were increased in the 37 examined CRC tissues compared to the adjacent normal tissues.Oxa induced PGFS expression in the parental HCT116 and HCT8 cells in a dosedependent manner.Furthermore,overexpression of PGFS in parental CRC cells significantly attenuated Oxainduced proliferative suppression,apoptosis,and DNA damage.In contrast,knockdown of PGFS in Oxa-resistant HCT116 and HCT8 cells(HCT116-OxR and HCT8-OxR)accentuated the effect of Oxa treatment in vitro and in vivo.The addition of the PGFS inhibitor indomethacin enhanced the cytotoxicity caused by Oxa.Treatment with the PGFS-catalyzed product PGF_(2α)reversed the effect of PGFS knockdown on Oxa sensitivity.Interestingly,PGFS inhibited the formation of platinum-DNA adducts in a PGF_(2α)-independent manner.PGF_(2α)exerts its protective effect against DNA damage by reducing ROS levels.CONCLUSION PGFS promotes resistance to Oxa in CRC via both PGF_(2α)-dependent and PGF_(2α)-independent mechanisms.
基金The study was reviewed and approved by the Institutional Review Board of The First Affiliated Hospital of Gannan Medical College,No.20141219.
文摘BACKGROUND Clinical prognosis often worsens due to high recurrence rates following radical surgery for colon cancer.The examination of high-risk recurrence factors post-surgery provides critical insights for disease evaluation and treatment planning.AIM To explore the relationship between metastasis-associated factor-1 in colon cancer(MACC1)and vacuolar ATP synthase(V-ATPase)expression in colon cancer tissues,and recurrence rate in patients undergoing radical colon cancer surgery.METHODS We selected 104 patients treated with radical colon cancer surgery at our hospital from January 2018 to June 2021.Immunohistochemical staining was utilized to assess the expression levels of MACC1 and V-ATPase in these patients.RESULTS The rates of MACC1 and V-ATPase positivity were 64.42%and 67.31%,respe-ctively,in colon cancer tissues,which were significantly higher than in paracan-cerous tissues(P<0.05).Among patients with TNM stage III,medium to low differentiation,and lymph node metastasis,the positive rates of MACC1 and V-ATPase were significantly elevated in comparison to patients with TNM stage I-II,high differentiation,and no lymph node metastasis(P<0.05).The rate of MACC1 positivity was 76.67%in patients with tumor diameters>5 cm,notably higher than in patients with tumor diameters≤5 cm(P<0.05).We observed a positive correlation between MACC1 and V-ATPase expression(rs=0.797,P<0.05).The positive rates of MACC1 and V-ATPase were significantly higher in patients with recurrence compared to those without(P<0.05).Logistic regression analysis revealed TNM stage,lymph node metastasis,MACC1 expression,and V-ATPase expression as risk factors for postoperative colon cancer recurrence(OR=6.322,3.435,2.683,and 2.421;P<0.05).CONCLUSION The upregulated expression of MACC1 and V-ATPase in colon cancer patients appears to correlate with clinicopathological features and post-radical surgery recurrence.
基金the Key Technology Development Foundation of Hubei Province, No. 20002B33
文摘BACKGROUND: At present, inhalation of nitrogen monoxidum (NO) or other angiotenic is widely used to cure hypoxic pulmonary artery hypertension. In addition, recent researches demonstrate that postganglionic fiber of stellate ganglion can regulate contents of blood vessel endothelium-calcitonin gene-related peptide (BVE-CGRP) and nitricoxide synthase (NOS) in lung tissue. Therefore, stellate ganglion which is blocked with the local anesthetic may cause therapeutic effects on hypoxic pulmonary artery hypertension. OBJECTIVE: To observe the effects of stellate block on calcitonin gene-related peptide (CGRP) of vasodilation factors, prostacyclin, endothelin-i of vasoconstriction factors, thromboxan, blood vessel endothelium-nitricoxide synthase (BVE-NOS) and mean arterial pressure of lung tissue in rabbits with hypoxic pulmonary artery hypertension. DESIGN: Randomly controlled animal study. SETTING: Neurological Institute of Taihe Hospital Affiliated to Yunyang Medical College. MATERIALS: A total of 24 adult Japanese rabbits of both genders and weighing 2.3 - 2.6 kg were provided by Animal Experimental Center of Hubei Academy of Medical Science. SP kit was provided by Beijing Zhongshan Biotechnology Co., Ltd.; moreover, kits of endothelin-1, CGRP, prostacyclin and thromboxan were provided by Radioimmunity Institute, Scientific and Technological Developing Center, General Hospital of Chinese PLA, and color image analytical system (Leica-Q500IW) was made in Germany. METHODS:The experiment was carried out in the Neurological Institute of Taihe Hospital affiliated to Yunyang Medical College from February to December 2002. ① Rabbits were performed with aseptic manipulation to exposure left stellate ganglion and then it was put in epidural catheter for 1 week. In addition, one end of epidural catheter was fixed near by stellate ganglion and the other end was fixed through dorsal neck. All rabbits were randomly divided into 4 groups, including normal control group, stellate block group, hypoxia group and hypoxia + stellate block group, with 6 in each group. Rabbits in the normal control group were perfused with saline through epidural catheter with 0.5 mL once for three times per day and 3 successive days in total; in addition, rabbits in the stellate block group were perfused with 2.5 g/L bupivacaine through epidural catheter with 0.5 mL once for three times per day and 3 successive days in total. Rabbits in the hypoxia group were used to establish hypoxic pulmonary artery hypertension models. That was to say, the experimental rabbits were put in hypoxic box (containing sodalime and calcium chloride to absorb CO2 and water) and given various flows of oxygen and nitrogen through the two lateral wells simultaneously. And then, oxygen was monitored with oxygen-concentration monitoring device to control the concentration in (10±2)% for 8 hours per day and 2 successive weeks in total. Rabbits in the hypoxia + stellate block group were used to establish hypoxia models as the same as those in the hypoxia group. Two weeks later, 2.5 g,/L bupivacaine was pushed into epidural catheter with 0.5 mL once for three times per day and 3 successive days in total. Breast was directly opened to measure mean pulmonary artery pressure.② 6 mL blood was collected through pulmonary arterial duct to measure levels of plasma CGRP, prostacyclin, endothelin-I and thromboxane with radio-immunity technique; meanwhile, immunohistochemical staining was used to observe the changes of BVE-NOS content of the experimental rabbits in all groups. MAIN OUTCOME MEASURES: Changes of CGRP, prostacyclin, endothelin-1 and thromboxane and BVE-NOS. RESULTS: A total of 24 experimental rabbits were involved in the final analysis. ①As compared with those in the normal control group, hypoxic pulmonary artery hypertension of the experimental rabbits was higher in the hypoxia group and hypoxia + stellate block group after hypoxia [(3.8±0.30), (3.16±0.45), (2.60± 0.27) kPa, P 〈 0.05, 0.01]; CGRP was lower [(68.20 ±8.78), (108.24 ±14.35), (130.25 ±22.70) ng/L, P 〈 0.05, 0.01]; prostacyclin was lower [(94.45± 10.68), (98.77± 12.31), (155.27±20.67) ng/L, P 〈 0.01]; endothelin-1 was higher [(184.7±29.66), (115.27± 13.62), (98.20±11.52), ng/L, P 〈 0.05, 0.01]; thromboxan was higher [(226.27 ±30.46), (207.67 ±27.32), (124.25 ± 16.89) ng/L, P 〈 0.01 ]. As compared with that in hypoxia group, hypoxic pulmonary artery hypertension was decreased in hypoxia + stellate block group (P 〈 0.05), CGRP was increased (P 〈 0.01), and endothelin-1 was decreased remarkably (P 〈 0.05). ② Level of BVE-NOS of the experimental rabbits was higher in stellate block group, hypoxia group and hypoxia + stellate block group than that in the normal control group [(0.25±0.06), (0.27±0.07), (0.46± 0.12), (0.14±0.03), P 〈 0.05], and NOS level was higher in the hypoxia + stellate block group than that in hypoxia group (P 〈 0.05). CONCLUSION: Mean arterial pressure is decreased in rabbits with hypoxic pulmonary artery hypertension after stellate block and level of endothelin-1 is also decreased; however, levels of CGRP and NOS are increased respectively.
文摘<abstract>Aim: To investigate the effect of aging on the expression of nitric oxide synthase I (NOS I) and the activity of NOS in rat penis. Methods: Sixty male rats from 3 age groups (adult, old and senescent) were investigated. The expression of NOS I protein and mRNA in rat penis were detected by Western blot and RT-PCR respectively and the NOS activity, with ultraviolet spectrophotometry. Results: In the old and senescent group, NOS I protein expression was significantly decreased as compared with the adult. NOS I mRNA expression was well correlated with the protein expression. NOS activity was not statistically different between the adult and old groups, but it was significantly reduced in the senescent compared with the adult group (P<0.01). Conclusion: The aging-induced decreases in NOS I expression and NOS activity may be one of the main mechanisms leading to erectile dysfunction in the senescent rats.
文摘Aim: To investigate the effect of cavernous nerve injury on the nNOS-containing nerve fibers in rat corpus cavernosum.Methods: Thirty-three male SD rats were randomized into 3 groups: 5 rats underwent pelvic exploration without tran-section of cavernous nerve as the sham-operated controls, the unilateral injury group (14 rats) had the cavernous nerve cuton one side, and the bilateral injury group (14 rats) had the nerves cut on both sides. Corpora cavernosa were harvestedat the 3rd week and 6th month after surgery, nNOS-positive nerve fibers were examined with strepavidin peroxidase im-munohistochemistry techniques (SP method). Results: After bilateral ablation, the nNOS-positive nerve fibers weresignificantly decreased at both the 3rd week ( 17 ± 4) and the 6th month (16 ± 4). For the unilateral injury group, thenNOS-positive nerve fibers were similarly decreased on the side of the neurotomy at the 3rd week (18 ± 6), but by the 6thmonth, the number increased significantly (61±9) and approximated the level on the contralateral side (81 ± 13). Con-clusion: In rats after unilateral cavernous nerve ablation, nNOS-containing nerve fibers might regenerate 6 months afteroperation, but regeneration did not occur in animals with bilateral cavernous nerve injury. Results suggest that duringpelvic radical surgery, the cavernous nerve should be preserved at least on one side in order to accomplish adequate regen-eration. (Asian J Androl 1999 Sep ; 1: 135 - 138)
文摘BACKGROUND: Abnormal changes in magnesium ion are closely related to cerebral injury. At present, some evidence indicates that magnesium reagent can improve nerve function and prognosis of patients with cerebral injury. OBJECTIVE: To observe the effect of magnesium sulfate on changes in nitric oxide synthase (NOS) activity in brain tissue of rats with acute craniocerebral injury. DESIGN: Completely randomized grouping design and randomly controlled study. SETTING: Laboratory of Neurosurgery, the Third Hospital of Chinese PLA. MATERIALS: Fifty-four male SD rats of clean grade and weighing 220 - 250 g were randomly divided into normal control group (n =6), cerebral injury group (n =24) and magnesium sulfate group (n =24). Especially, rats in cerebral injury group and magnesium sulfate group were equally divided into four subgroups and observed at 0.5, 2, 6 and 24 hours after model establishment. A solution of 125 g/L of magnesium sulfate was provided by the Seventh Pharmaceutical Factory of Wuxi and the NOS assay kit by Nanjing Jiancheng Bioengineering Institute. METHODS: The experiment was carried out in the Institute of Neurosurgery, the Third Hospital of Chinese PLA from August 2000 to August 2002. ① Rats in the cerebral injury group and magnesium sulfate group were anesthetized to establish cerebral injury models based on modified Feeney technique; magnesium sulfate group were intraperitoneally injected 600 mg/kg magnesium sulfate (125 g/L), but rats in the normal control group remained untreated. ② At 0.5, 2, 6 and 24 hours after cerebral injury, rats in cerebral injury group and magnesium sulfate group were decapitated and brains were dissected. Cerebral cortex of rats in cerebral injury group was selected for NOS assay; in addition, at 0.5 hour after cerebral injury, a portion of the parietal lobe was selected from the brains of rats in the normal control group. Brain samples were homogenized, the homogenated centrifuged and the supernatants were used to measure NOS activity with NOS kit. ③ Differences among the three groups were compared with t test. MAIN OUTCOME MEASURES: NOS activity in cerebral cortex of rats in each group. RESULTS: A total of 54 SD rats were involved in the final analysis. At 0.5 hour after cerebral injury, NOS activity in cerebral cortex was (42.45 ± 13.46) nmol/L in cerebral injury group and (41.17 ± 12.53) nmol/L in magnesium sulfate group, respectively, which was higher than that in normal control group [(39.45 ± 11.84) nmol/L, P 〈 0.05]. At 2 hours after cerebral injury, NOS activities were (66.48 ±21.43) and (63.24 ± 19.18) umol/L, respectively, while at 6 hours after cerebral injury, NOS activities were (62.45 ± 24.18) and (51.97 ±20.46) nmol/L, respectively, which were higher than those in normal control group (P 〈 0.0 1). At 24 hours after cerebral injury, NOS activity returned to basal level. Moreover, NOS activity was significantly lower in the magnesium sulfate group than that in the cerebral injury group at 2 and 6 hours after cerebral injury (P 〈 0.05, 0.01).CONCLUSION: NOS activity is increased in injured brain tissue of rats with craniocerebral injury, and treatment with magnesium sulfate provides some degrees of protection possibly through inhibition of NOS activity after cerebral injury.