Some haplotypes of the sucrose synthase gene TaSus1 are associated with thousand-grain weight(TGW)in wheat(Triticum aestivum L.).However,no mutations have been identified within the gene to test this association.The e...Some haplotypes of the sucrose synthase gene TaSus1 are associated with thousand-grain weight(TGW)in wheat(Triticum aestivum L.).However,no mutations have been identified within the gene to test this association.The effects of TaSus1 on grain number per spike(GNS)also are largely unknown.Our previous genome-wide association study identified TaSus-A1 as a candidate gene controlling fertile spikelet number per spike(FSN).In the present study,we generated two independent mutants for the three TaSus1 homoeologs by CRISPR/Cas9-mediated genome editing.The triple mutants displayed lower FSN,GNS,grain number per spikelet(GNST),and TGW than wild-type plants.In 306 hexaploid wheat accessions,two single-nucleotide polymorphisms in TaSus-A1 contributed differently to GNS.Introgression of the two alleles into a wheat genetic background confirmed their effects.The alleles differed in geographical distribution among the accessions.展开更多
Ghrelin is a 28 amino acid peptide mainly derived from the oxyntic gland of the stomach. Both acylated(AG) and unacylated(UAG) forms of ghrelin are found in the circulation. Initially, AG was considered as the only bi...Ghrelin is a 28 amino acid peptide mainly derived from the oxyntic gland of the stomach. Both acylated(AG) and unacylated(UAG) forms of ghrelin are found in the circulation. Initially, AG was considered as the only bioactive form of ghrelin. However, recent advances indicate that both AG and UAG exert distinct and common effects in organisms. Soon after its discovery, ghrelin was shown to promote appetite and adiposity in animal and human models. In response to these anabolic effects, an impressive number of elements have suggested the influence of ghrelin on the regulation of metabolic functions and the development of obesityrelated disorders. However, due to the complexity ofits biochemical nature and the physiological processes it governs, some of the effects of ghrelin are still debated in the literature. Evidence suggests that ghrelin influences glucose homeostasis through the modulation of insulin secretion and insulin receptor signaling. On the other hand, insulin was also shown to influence circulating levels of ghrelin. Here, we review the relationship between ghrelin and insulin and we describe the impact of this interaction on the modulation of glucose homeostasis.展开更多
This review on current biotechnological methods in forestry for in vitro tissue cultures to define the effect of stress conditions on trees,concentrates on somatic embryogenesis.Callus tissue,the key product of somati...This review on current biotechnological methods in forestry for in vitro tissue cultures to define the effect of stress conditions on trees,concentrates on somatic embryogenesis.Callus tissue,the key product of somatic embryogenesis,grows over a tree wound under ex vitro conditions.Callus tissue can be used in research in areas such as pathogenic susceptibility at the embryonic level,effect of heavy metals,influence of low temperatures(cryopreservation),production of secondary metabolites and transformation of plants.Callus of arborescent plants can be induced in vitro by fungal elicitors to produce secondary metabolites for pharmaceutical and cosmetic industries and are strongly repellant to herbivores and can thus act to protect forests.Analyses of dual cultures demonstrated that callus tissue exposed to a pathogenic fungus responds by synthesizing low-molecular-mass proteins belonging to an immune protein class.Cryopreservation of embryonic callus tissue also has broad applications,e.g.,for valuable plant genotypes in gene banks.Without strategies to protect forests against stressfactors,forest ecosystems will degrade to the detriment of all life,including humans.In vitro biotechnological research using callus tissue contributes to progress in forestry and the disciplines of ecology,physiology,phytopathology,culture and selection of plants.展开更多
Grain size,characterized by a combination of grain length,width,and thickness,is one of the major determinants of yield in rice.The present study identified TATA-box binding protein-associated factor 2(TAF2)as an esse...Grain size,characterized by a combination of grain length,width,and thickness,is one of the major determinants of yield in rice.The present study identified TATA-box binding protein-associated factor 2(TAF2)as an essential component regulating transcription and determining grain size in rice.Map-based cloning showed that a G/T substitution in TAF2 resulted in a naturally occurring mutant called reduced grain size and plant height 1(rgh1).The mutants,with weak edited rgh1 alleles,exhibited a small grain phenotype with reduced grain length and width,while the severe knockout mutant(rgh1-2s)was dwarf and completely sterile.Allelic test performed between rgh1 and several edited alleles confirmed that the mutation in TAF2 caused the rgh1 phenotype.GUS staining showed that TAF2 was mainly expressed in the vascular bundles of roots,stems,leaves,and grains.The cytological analysis revealed that reduced cell division in the glumes resulted in the small grain phenotype of rgh1.Further RNA-sequencing detected altered expression of genes involved in the basic biological processes in rgh1 mutant.These findings provide novel insights into the TAF2-mediated genetic mechanism regulating grain size in rice.展开更多
Background:The expression of pyruvate kinase muscle 2(PKM2)is augmented in macrophages of patients with atherosclerotic coronary artery disease.The role of PKM2 in atherosclerosis is to be determined.Methods:Global an...Background:The expression of pyruvate kinase muscle 2(PKM2)is augmented in macrophages of patients with atherosclerotic coronary artery disease.The role of PKM2 in atherosclerosis is to be determined.Methods:Global and myeloid cell-specific PKM2 knock-in mice with ApoE^(-/-)background(ApoE^(-/-),PKM2^(KI/KI)and Lyz2-cre,ApoE^(-/-),and PKM2^(flox/flox))were produced to evaluate the clinical significance of PKM2 in atherosclerosis development.Wild-type and PKM2 knock-in macrophages were isolated to assess the function of PKM2 in macrophage phagocytosis.Atherosclerotic mice were treated with PKM2 inhibitor shikonin(SKN)to evaluate the therapeutic potential of PKM2 suppression in atherosclerosis.Results:Oxidized low-density lipoprotein(oxLDL)upregulated PKM2 in macrophages.PKM2 in return promoted the uptake of oxLDL by macrophages.Overexpressed PKM2 accelerated atherosclerosis in mice.SKN blocked the progress of mouse atherosclerosis.Conclusions:PKM2 accelerates macrophage phagocytosis and atherosclerosis.Targeting PKM2 is a potential therapy for atherosclerosis.展开更多
The present study was performed mainly to investigate the antagonist-pathogen-host interaction in wounds of the sweet cherry fruits. The antagonistic yeast Cryptococcus laurentii could significantly reduce the brown r...The present study was performed mainly to investigate the antagonist-pathogen-host interaction in wounds of the sweet cherry fruits. The antagonistic yeast Cryptococcus laurentii could significantly reduce the brown rot of the sweet cherry fruit caused by Monilinia fructicola at 25 and 1 ℃. The populations of yeast increased faster in the presence of the pathogen initially, but then decreased rapidly. In the fruits inoculated with M. fructicola alone or combined with C. laurentii, an induction of lipid peroxidation as well as activities of the antioxidant enzymes, such as, superoxide dismutases (SOD), catalase (CAT), and peroxidase (POD), was observed. The isoenzyme pattern of polypheno/oxidase (PPO) changed greatly after the symptoms appeared, with new PPO isoforms being induced. By contrast, the induction of lipid peroxidation and activities of SOD, CAT, and POD were low, although no significant changes were found in the PPO isoenzyms in the fruits inoculated with antagonist C. laurentii alone. The inhibition of brown rot during the antagonist- pathogen-host interaction in wounds of the sweet cherry fruits was mainly on account of the stimulated growth of C. laurentii as well as the induction of antioxidant enzymes of the fruits by M. fructicola.展开更多
Anatomical and chemical characteristics of stems affect lodging in wheat(Triticum aestivum L.) cultivars. Traits associated with lodging resistance, such as plant height, stem strength, culm wall thickness, pith diame...Anatomical and chemical characteristics of stems affect lodging in wheat(Triticum aestivum L.) cultivars. Traits associated with lodging resistance, such as plant height, stem strength, culm wall thickness, pith diameter, and stem diameter, were extensively investigated in earlier studies. However, the solid stem trait was rarely considered. In this study, we measured a range of anatomical and chemical characteristics on solid and hollow stemmed wheat cultivars. Significant correlations were detected between resistance to lodging and several anatomical features, including width of mechanical tissue, weight of low internodes, and width of stem walls. Morphological features that gave the best indication of improved lodging resistance were increased stem width, width of mechanical tissue layer, and stem density. Multiple linear regression analysis showed that 99% of the variation in lodging resistance could be explained by the width of the mechanical tissue layer, suggesting that solid stemmed wheat has several anatomical features for increasing resistance to lodging. In addition, microsatellite markers GWM247 and GWM340 were linked to a single solid stem QTL on chromosome 3BL in a population derived from the cross Xinongshixin(solid stem)/Line 3159(hollow stem). These markers should be valuable in breeding wheat for solid stem.展开更多
Heterotrimeric G proteins are known to function as messengers in numerous signal transduction pathways.The nullmutation of RGA(rice heterotrimeric G protein α subunit),which encodes the α subunit of heterotrimeric G...Heterotrimeric G proteins are known to function as messengers in numerous signal transduction pathways.The nullmutation of RGA(rice heterotrimeric G protein α subunit),which encodes the α subunit of heterotrimeric G proteinin rice,causes severe dwarfism and reduced responsiveness to gibberellic acid in rice.However,less is known aboutheterotrimeric G protein in brassinosteroid(BR)signaling,one of the well-understood phytohormone pathways.In thepresent study,we used root elongation inhibition assay,lamina inclination assay and coleoptile elongation analysis todemonstrated reduced sensitivity of dl mutant plants(caused by the null mutation of RGA)to 24-epibrassinolide(24-epiBL),which belongs to brassinosteroids and plays a wide variety of roles in plant growth and development.Moreover,RGA transcript level was decreased in 24-epiBL-treated seedlings in a dose-dependent manner.Our results show thatRGA is involved in rice brassinosteroid response,which may be beneficial to elucidate the molecular mechanisms of Gprotein signaling and provide a novel perspective to understand BR signaling in higher plants.展开更多
AIM:To investigate the effect and mechanism of acupuncture at heterotopic acupoints on jejunal motility,particularly in pathological conditions.METHODS:Jejunal motility was assessed using a manometric balloon placed i...AIM:To investigate the effect and mechanism of acupuncture at heterotopic acupoints on jejunal motility,particularly in pathological conditions.METHODS:Jejunal motility was assessed using a manometric balloon placed in the jejunum approximately18-20 cm downstream from the pylorus and filled with approximately 0.1 m L warm water in anesthetized normal rats or rats with diarrhea or constipation.The heterotopic acupoints including LI11(Quchi),ST37(Shangjuxu),BL25(Dachangshu),and the homotopic acupoint ST25(Tianshu),and were stimulated for 60 s by rotating acupuncture needles right and left at a frequency of 2 Hz.To determine the type of afferent fibers mediating the regulation of jejunal motility by manual acupuncture,the ipsilateral sciatic A or C fibers of ST37 were inactivated by local application of the A-fiber selective demyelination agent cobra venom or the C fiber blocker capsaicin.Methoctramine,a selective M2 receptor antagonist,was injected intravenously to identify a specific role for M2 receptors in mediating the effect of acupuncture on jejunal motility.RESULTS:Acupuncture at heterotopic acupoints,such as LI11 and ST37,increased jejunal motility not only in normal rats,but also in rats with constipation or diarrhea.In normal rats,manual acupuncture at LI11 or ST37 enhanced jejunal pressure from 7.34±0.19 cmH2O to 7.93±0.20 cm H2O,an increase of 9.05%±0.82%(P<0.05),and from 6.95±0.14 cm H2O to 8.97±0.22cm H2O,a significant increase of 27.44%±1.96%(P<0.01),respectively.In constipated rats,manual acupuncture at LI11 or ST37 increased intrajejunal pressure from8.17±0.31 cm H2O to 9.86±0.36 cm H2O,an increase of 20.69%±2.10%(P<0.05),and from 8.82±0.28cm H2O to 10.83±0.28 cm H2O,an increase of 22.81%±1.46%(P<0.05),respectively.In rats with diarrhea,MA at LI11 or ST37 increased intrajejunal pressure from 11.95±0.35 cm H2O to 13.96±0.39 cm H2O,an increase of 16.82%±2.35%(P<0.05),and tended to increase intrajejunal pressure(from 12.42±0.38 cm H2O to 13.05±0.38 cm H2O,an increase of 5.07%±1.08%,P>0.05),respectively.In contrast,acupuncture ST25,a homotopic acupoint,decreased not only intrajejunal pressure,but also significantly decreased frequency in normal rats and rats with constipation or diarrhea.Following demyelination of Aδfibers,acupuncture at ST37again augmented intrajejunal pressure to 121.48%±3.06%of baseline.Following capsaicin application for24 h,acupuncture at ipsilateral ST37 increased intrajejunal pressure significantly to 106.63%±1.26%of basallevels when compared to measurements prior to capsaicin treatment(P<0.05).Acupuncture at LI11,ST37,or BL25 significantly rescued methoctramine-mediated inhibition of jejunal motility amplitude from 42.83%±1.65%to 53.43%±1.95%of baseline(P<0.05),from45.15%±2.22%to 70.51%±2.34%of baseline(P<0.01),and from 38.03%±2.34%to 70.12%±2.22%of baseline(P<0.01),respectively.CONCLUSION:Acupuncture at heterotopic acupoints increases the amplitude of jejunal motility in rats.C fibers and M2 receptors predominantly and partially mediate the regulation of jejunal motility by acupuncture,respectively.展开更多
Repolarization heterogeneity(RH)is an intrinsic property of ventricular myocardium and the reason for T-wave formation on electrocardiogram(ECG).Exceeding the physiologically based RH level is associated with appearan...Repolarization heterogeneity(RH)is an intrinsic property of ventricular myocardium and the reason for T-wave formation on electrocardiogram(ECG).Exceeding the physiologically based RH level is associated with appearance of life-threatening ventricular arrhythmias and sudden cardiac death.In this regard,an accurate and comprehensive evaluation of the degree of RH parameters is of importance for assessment of heart state and arrhythmic risk.This review is devoted to comprehensive consideration of RH phenomena in terms of electrophysiological processes underlying RH,cardiac electric field formation during ventricular repolarization,as well as clinical significance of RH and its reflection on ECG parameters.The formation of transmural,apicobasal,left-toright and anterior-posterior gradients of action potential durations and end of repolarization times resulting from the heterogenous distribution of repolarizing ion currents and action potential morphology throughout the heart ventricles,and the different sensitivity of myocardial cells in different ventricular regions to the action of pharmacological agents,temperature,frequency of stimulation,etc.,are being discussed.The review is focused on the fact that RH has different aspects–temporal and spatial,global and local;ECG reflection of various RH aspects and their clinical significance are being discussed.Strategies for comprehensive assessment of ventricular RH using different ECG indices reflecting various RH aspects are presented.展开更多
AIM: To observe the effect of electroacupuncture (EA) of "Neiguan" (PC6) and "Gongsun" (SP4) on pathological changes of the heart and stomach in rats with acute myocardial ischemia (AMI), and to ex...AIM: To observe the effect of electroacupuncture (EA) of "Neiguan" (PC6) and "Gongsun" (SP4) on pathological changes of the heart and stomach in rats with acute myocardial ischemia (AMI), and to explore its underlying mechanism. METHODS: Fifty Wistar rats were randomized into control, model, PC6, SP4 and PC6 + SP4 groups (n = 8 each group). An AMI model was established by occlusion of the descending anterior branch (DAB) of the left coronary artery. ECG-ST of cervico-thoracic lead and electrogastrogram (EGG) were recorded. EA was applied to PC6, SP4 and PC6 + SP4 groups, respectively. At the end of experiments, the rats were transcardically perfused with 4% paraformaldehyde, and the heart base myocardium, gastric antrum and duodenum tissues were sampled, sectioned and stained with a reduced form of nicotinamide- adenine dinucleotide phosphate (NADPH)-diaphorase histochemical method for displaying nitric oxide synthase (NOS) activity. RESULTS: After AMI, ECG-ST values elevated. After EA, the elevated ECG-ST values at 20 min in PC6group, at 30 min in PC6 + SP4 and SP4 groups had no significant differences in comparison with their respective basal values before AMI. Following AMI, the amplitude and frequency of slow waves of EGG decreased remarkably (P < 0.05). At 30 min after EA, the mean amplitude and frequency of slow waves of EGG in the three EA groups had no marked differences compared with their individual basal levels and those in the control group. After AMI, the mean integral grey values of NOS-positive product in myocardium, gastric antrum and duodenum tissues in the model group increased remarkably in comparison with the control group, while those in three EA groups were lower than those in the model group. No significant differences were found in ECG-ST and EGG improvement among the three EA groups. However, EA of PC6 had a better effect on ECG-ST and EA of PC4 had a better effect on EGG, respectively. CONCLUSION: EA of PC6, SP4 and PC6 + SP4 can significantly promote the recovery of cardiac and gastric electrical activities after AMI, and up-regulate NOS expression in myocardium, gastric antrum and duodenum tissues.展开更多
Objective To examine the effects of urotensin Ⅱ (UII) on the discharges of neurons in CA1 area of hipp-ocampal slices by using extracellular recording technique. Results (1)In response to the application of UII (0.3 ...Objective To examine the effects of urotensin Ⅱ (UII) on the discharges of neurons in CA1 area of hipp-ocampal slices by using extracellular recording technique. Results (1)In response to the application of UII (0.3 , 3.0, 30.0, 300.0 nmol/L, n=77) into the perfusate for 2 min, the spontaneous discharge rates (SDR) of 63/77 (81.8%) neurons were significantly decreased in a dose-dependent manner. (2)Pretreatment with bicuculline(BIC,100μmol/L) , a specific GABAA receptor antagonist, led to a marked increase in the SDR of 6/7 (85.71% ) neurons in an epileptiform pattern. The increased discharges were not significantly changed after UII (30.0 nmol/L) was applied into the perfusate for 2 min. (3) Pretreatment with picrotoxin (PIC, 50μmol/L) , a selective blocker of Cl- channel, led to an increase in the SDR of all 8/8(100% ) neurons. The increased discharges were not influenced by the UII (30.0 nmol/L) applied. (4)Application of nitric oxide synthase (NOS) inhibitor NG-nitro-L-arginine methyl ester (L-NAME, 50μmol/L) into the perfusate for 2 min also significantly augmented the SDR of 14/16 (87.5% ) neurons , then UII (30. 0 nmol/L) applied into the perfusate reduced the increased the SDR of all 14/14 ( 100% ) neurons. Conclusion These results suggest that UII may decrease neuronal activity by potentiating GABAA receptor-mediated Cl- current in hippocampal CA1 neurons, and involved with the mediation of nitric oxide.展开更多
The inhibitory effect of gadolinium on Sinorhizobium fredii USDA 205 was studied on a global scale using twodimensional gel electrophoresis and MALDI-TOF MS. The results indicated that 22 proteins were significantly a...The inhibitory effect of gadolinium on Sinorhizobium fredii USDA 205 was studied on a global scale using twodimensional gel electrophoresis and MALDI-TOF MS. The results indicated that 22 proteins were significantly affected by 1 mmol · L^-1 Gd^3 + treatment when compared with an untreated control. Among these proteins, nine were up-regulated and thirteen were down-regulated. The differently expressed proteins were classified into 8 functional categories based on their functions, including transporters, proteins for cellular defence, and proteins involved in metabolism.展开更多
Although electrical stimulation is therapeutically applied for neural regeneration in patients, it remains unclear how electrical stimulation exerts its effects at the molecular level on spinal cord injury (SCI). To...Although electrical stimulation is therapeutically applied for neural regeneration in patients, it remains unclear how electrical stimulation exerts its effects at the molecular level on spinal cord injury (SCI). To identify the signaling pathway involved in electrical stimulation improving the function of injured spinal cord, 21 female Sprague-Dawley rats were randomly assigned to three groups: control (no surgical intervention, n = 6), SCI (SCI only, n = 5), and electrical simulation (ES; SCI induction followed by ES treatment, n = 10). A complete spinal cord transection was performed at the 10^th thoracic level. Electrical stimulation of the injured spinal cord region was applied for 4 hours per day for 7 days. On days 2 and 7 post SCI, the Touch-Test Sensory Evaluators and the Basso-Beattie-Bresnahan locomotor scale were used to evaluate rat sensory and motor function. Somatosensory-evoked potentials of the tibial nerve of a hind paw of the rat were measured to evaluate the electrophysiological function of injured spinal cord. Western blot analysis was performed to measure p38-RhoA and ERK1/2-Bcl-2 pathways related protein levels in the injured spinal cord. Rat sensory and motor functions were similar between SCI and ES groups. Com- pared with the SCI group, in the ES group, the latencies of the somatosensory-evoked potential of the tibial nerve of rats were significantly shortened, the amplitudes were significantly increased, RhoA protein level was significantly decreased, protein gene product 9.5 expression, ERK1/2, p38, and Bcl-2 protein levels in the spinal cord were significantly increased. These data suggest that ES can promote the recovery of electrophysiological function of the injured spinal cord through regulating p38-RhoA and ERK1/2-Bcl-2 pathway-related protein levels in the injured spinal cord.展开更多
基金This work was supported by the Strategic Priority Research Program of Chinese Academy of Sciences(XDA24010104-2).
文摘Some haplotypes of the sucrose synthase gene TaSus1 are associated with thousand-grain weight(TGW)in wheat(Triticum aestivum L.).However,no mutations have been identified within the gene to test this association.The effects of TaSus1 on grain number per spike(GNS)also are largely unknown.Our previous genome-wide association study identified TaSus-A1 as a candidate gene controlling fertile spikelet number per spike(FSN).In the present study,we generated two independent mutants for the three TaSus1 homoeologs by CRISPR/Cas9-mediated genome editing.The triple mutants displayed lower FSN,GNS,grain number per spikelet(GNST),and TGW than wild-type plants.In 306 hexaploid wheat accessions,two single-nucleotide polymorphisms in TaSus-A1 contributed differently to GNS.Introgression of the two alleles into a wheat genetic background confirmed their effects.The alleles differed in geographical distribution among the accessions.
基金Supported by Fonds de Recherche du Québec en Santé(toLaplante M and St-Pierre DH)Operating grants from NaturalSciences and Engineering Research Council of Canada and Diabète QuébecLaplante M also holds operating grants from the Canadian Institutes of Health Research,Canadian Liver Foundation and the Fondation de l’Institut Universitaire de Cardiologieet de Pneumologie de Québec
文摘Ghrelin is a 28 amino acid peptide mainly derived from the oxyntic gland of the stomach. Both acylated(AG) and unacylated(UAG) forms of ghrelin are found in the circulation. Initially, AG was considered as the only bioactive form of ghrelin. However, recent advances indicate that both AG and UAG exert distinct and common effects in organisms. Soon after its discovery, ghrelin was shown to promote appetite and adiposity in animal and human models. In response to these anabolic effects, an impressive number of elements have suggested the influence of ghrelin on the regulation of metabolic functions and the development of obesityrelated disorders. However, due to the complexity ofits biochemical nature and the physiological processes it governs, some of the effects of ghrelin are still debated in the literature. Evidence suggests that ghrelin influences glucose homeostasis through the modulation of insulin secretion and insulin receptor signaling. On the other hand, insulin was also shown to influence circulating levels of ghrelin. Here, we review the relationship between ghrelin and insulin and we describe the impact of this interaction on the modulation of glucose homeostasis.
基金supported by DS 3414 theme from the Polish Ministry of Education and Science
文摘This review on current biotechnological methods in forestry for in vitro tissue cultures to define the effect of stress conditions on trees,concentrates on somatic embryogenesis.Callus tissue,the key product of somatic embryogenesis,grows over a tree wound under ex vitro conditions.Callus tissue can be used in research in areas such as pathogenic susceptibility at the embryonic level,effect of heavy metals,influence of low temperatures(cryopreservation),production of secondary metabolites and transformation of plants.Callus of arborescent plants can be induced in vitro by fungal elicitors to produce secondary metabolites for pharmaceutical and cosmetic industries and are strongly repellant to herbivores and can thus act to protect forests.Analyses of dual cultures demonstrated that callus tissue exposed to a pathogenic fungus responds by synthesizing low-molecular-mass proteins belonging to an immune protein class.Cryopreservation of embryonic callus tissue also has broad applications,e.g.,for valuable plant genotypes in gene banks.Without strategies to protect forests against stressfactors,forest ecosystems will degrade to the detriment of all life,including humans.In vitro biotechnological research using callus tissue contributes to progress in forestry and the disciplines of ecology,physiology,phytopathology,culture and selection of plants.
基金supported by the National Natural Science Foundation of China(31971918 and 32070348)the Chinese Academy of Sciences Innovation Project(XDA24010402).
文摘Grain size,characterized by a combination of grain length,width,and thickness,is one of the major determinants of yield in rice.The present study identified TATA-box binding protein-associated factor 2(TAF2)as an essential component regulating transcription and determining grain size in rice.Map-based cloning showed that a G/T substitution in TAF2 resulted in a naturally occurring mutant called reduced grain size and plant height 1(rgh1).The mutants,with weak edited rgh1 alleles,exhibited a small grain phenotype with reduced grain length and width,while the severe knockout mutant(rgh1-2s)was dwarf and completely sterile.Allelic test performed between rgh1 and several edited alleles confirmed that the mutation in TAF2 caused the rgh1 phenotype.GUS staining showed that TAF2 was mainly expressed in the vascular bundles of roots,stems,leaves,and grains.The cytological analysis revealed that reduced cell division in the glumes resulted in the small grain phenotype of rgh1.Further RNA-sequencing detected altered expression of genes involved in the basic biological processes in rgh1 mutant.These findings provide novel insights into the TAF2-mediated genetic mechanism regulating grain size in rice.
基金National Key R&D program of China,Grant/Award Number:2021YFC2500700The National Natural Science Foundation of China+1 种基金Grant/Award Number:81730078The Chinese Academy of Medical Sciences Initiative for Innovative Medicine,Grant/Award Number:2021-I2M-1-049。
文摘Background:The expression of pyruvate kinase muscle 2(PKM2)is augmented in macrophages of patients with atherosclerotic coronary artery disease.The role of PKM2 in atherosclerosis is to be determined.Methods:Global and myeloid cell-specific PKM2 knock-in mice with ApoE^(-/-)background(ApoE^(-/-),PKM2^(KI/KI)and Lyz2-cre,ApoE^(-/-),and PKM2^(flox/flox))were produced to evaluate the clinical significance of PKM2 in atherosclerosis development.Wild-type and PKM2 knock-in macrophages were isolated to assess the function of PKM2 in macrophage phagocytosis.Atherosclerotic mice were treated with PKM2 inhibitor shikonin(SKN)to evaluate the therapeutic potential of PKM2 suppression in atherosclerosis.Results:Oxidized low-density lipoprotein(oxLDL)upregulated PKM2 in macrophages.PKM2 in return promoted the uptake of oxLDL by macrophages.Overexpressed PKM2 accelerated atherosclerosis in mice.SKN blocked the progress of mouse atherosclerosis.Conclusions:PKM2 accelerates macrophage phagocytosis and atherosclerosis.Targeting PKM2 is a potential therapy for atherosclerosis.
基金the Knowledge Innovation Program of the Chinese Academy of Sciences, China (KSCX2-YW-G-010); the National Natural Science Foundation of China (30671473).
文摘The present study was performed mainly to investigate the antagonist-pathogen-host interaction in wounds of the sweet cherry fruits. The antagonistic yeast Cryptococcus laurentii could significantly reduce the brown rot of the sweet cherry fruit caused by Monilinia fructicola at 25 and 1 ℃. The populations of yeast increased faster in the presence of the pathogen initially, but then decreased rapidly. In the fruits inoculated with M. fructicola alone or combined with C. laurentii, an induction of lipid peroxidation as well as activities of the antioxidant enzymes, such as, superoxide dismutases (SOD), catalase (CAT), and peroxidase (POD), was observed. The isoenzyme pattern of polypheno/oxidase (PPO) changed greatly after the symptoms appeared, with new PPO isoforms being induced. By contrast, the induction of lipid peroxidation and activities of SOD, CAT, and POD were low, although no significant changes were found in the PPO isoenzyms in the fruits inoculated with antagonist C. laurentii alone. The inhibition of brown rot during the antagonist- pathogen-host interaction in wounds of the sweet cherry fruits was mainly on account of the stimulated growth of C. laurentii as well as the induction of antioxidant enzymes of the fruits by M. fructicola.
基金supported by the National Basic Research Program of China (2011CB100302)the Knowledge Innovation Program of CAS (KSCX2-EW-N-02)
文摘Anatomical and chemical characteristics of stems affect lodging in wheat(Triticum aestivum L.) cultivars. Traits associated with lodging resistance, such as plant height, stem strength, culm wall thickness, pith diameter, and stem diameter, were extensively investigated in earlier studies. However, the solid stem trait was rarely considered. In this study, we measured a range of anatomical and chemical characteristics on solid and hollow stemmed wheat cultivars. Significant correlations were detected between resistance to lodging and several anatomical features, including width of mechanical tissue, weight of low internodes, and width of stem walls. Morphological features that gave the best indication of improved lodging resistance were increased stem width, width of mechanical tissue layer, and stem density. Multiple linear regression analysis showed that 99% of the variation in lodging resistance could be explained by the width of the mechanical tissue layer, suggesting that solid stemmed wheat has several anatomical features for increasing resistance to lodging. In addition, microsatellite markers GWM247 and GWM340 were linked to a single solid stem QTL on chromosome 3BL in a population derived from the cross Xinongshixin(solid stem)/Line 3159(hollow stem). These markers should be valuable in breeding wheat for solid stem.
基金This project was supported by the Major State Basic Research Program of China (2005CB 120806), National Natural Science Foundation of China for Distinguished Young Scholars (30525026) and the State Transgenic Plant Project (JY04-A-01)
文摘Heterotrimeric G proteins are known to function as messengers in numerous signal transduction pathways.The nullmutation of RGA(rice heterotrimeric G protein α subunit),which encodes the α subunit of heterotrimeric G proteinin rice,causes severe dwarfism and reduced responsiveness to gibberellic acid in rice.However,less is known aboutheterotrimeric G protein in brassinosteroid(BR)signaling,one of the well-understood phytohormone pathways.In thepresent study,we used root elongation inhibition assay,lamina inclination assay and coleoptile elongation analysis todemonstrated reduced sensitivity of dl mutant plants(caused by the null mutation of RGA)to 24-epibrassinolide(24-epiBL),which belongs to brassinosteroids and plays a wide variety of roles in plant growth and development.Moreover,RGA transcript level was decreased in 24-epiBL-treated seedlings in a dose-dependent manner.Our results show thatRGA is involved in rice brassinosteroid response,which may be beneficial to elucidate the molecular mechanisms of Gprotein signaling and provide a novel perspective to understand BR signaling in higher plants.
基金Supported by National Basic Research Program of China grant(to Zhu B),No.2011CB505201National Natural Science Foundation of China No.81130063 and No.81173345(to Zhu B and Gao X)
文摘AIM:To investigate the effect and mechanism of acupuncture at heterotopic acupoints on jejunal motility,particularly in pathological conditions.METHODS:Jejunal motility was assessed using a manometric balloon placed in the jejunum approximately18-20 cm downstream from the pylorus and filled with approximately 0.1 m L warm water in anesthetized normal rats or rats with diarrhea or constipation.The heterotopic acupoints including LI11(Quchi),ST37(Shangjuxu),BL25(Dachangshu),and the homotopic acupoint ST25(Tianshu),and were stimulated for 60 s by rotating acupuncture needles right and left at a frequency of 2 Hz.To determine the type of afferent fibers mediating the regulation of jejunal motility by manual acupuncture,the ipsilateral sciatic A or C fibers of ST37 were inactivated by local application of the A-fiber selective demyelination agent cobra venom or the C fiber blocker capsaicin.Methoctramine,a selective M2 receptor antagonist,was injected intravenously to identify a specific role for M2 receptors in mediating the effect of acupuncture on jejunal motility.RESULTS:Acupuncture at heterotopic acupoints,such as LI11 and ST37,increased jejunal motility not only in normal rats,but also in rats with constipation or diarrhea.In normal rats,manual acupuncture at LI11 or ST37 enhanced jejunal pressure from 7.34±0.19 cmH2O to 7.93±0.20 cm H2O,an increase of 9.05%±0.82%(P<0.05),and from 6.95±0.14 cm H2O to 8.97±0.22cm H2O,a significant increase of 27.44%±1.96%(P<0.01),respectively.In constipated rats,manual acupuncture at LI11 or ST37 increased intrajejunal pressure from8.17±0.31 cm H2O to 9.86±0.36 cm H2O,an increase of 20.69%±2.10%(P<0.05),and from 8.82±0.28cm H2O to 10.83±0.28 cm H2O,an increase of 22.81%±1.46%(P<0.05),respectively.In rats with diarrhea,MA at LI11 or ST37 increased intrajejunal pressure from 11.95±0.35 cm H2O to 13.96±0.39 cm H2O,an increase of 16.82%±2.35%(P<0.05),and tended to increase intrajejunal pressure(from 12.42±0.38 cm H2O to 13.05±0.38 cm H2O,an increase of 5.07%±1.08%,P>0.05),respectively.In contrast,acupuncture ST25,a homotopic acupoint,decreased not only intrajejunal pressure,but also significantly decreased frequency in normal rats and rats with constipation or diarrhea.Following demyelination of Aδfibers,acupuncture at ST37again augmented intrajejunal pressure to 121.48%±3.06%of baseline.Following capsaicin application for24 h,acupuncture at ipsilateral ST37 increased intrajejunal pressure significantly to 106.63%±1.26%of basallevels when compared to measurements prior to capsaicin treatment(P<0.05).Acupuncture at LI11,ST37,or BL25 significantly rescued methoctramine-mediated inhibition of jejunal motility amplitude from 42.83%±1.65%to 53.43%±1.95%of baseline(P<0.05),from45.15%±2.22%to 70.51%±2.34%of baseline(P<0.01),and from 38.03%±2.34%to 70.12%±2.22%of baseline(P<0.01),respectively.CONCLUSION:Acupuncture at heterotopic acupoints increases the amplitude of jejunal motility in rats.C fibers and M2 receptors predominantly and partially mediate the regulation of jejunal motility by acupuncture,respectively.
文摘Repolarization heterogeneity(RH)is an intrinsic property of ventricular myocardium and the reason for T-wave formation on electrocardiogram(ECG).Exceeding the physiologically based RH level is associated with appearance of life-threatening ventricular arrhythmias and sudden cardiac death.In this regard,an accurate and comprehensive evaluation of the degree of RH parameters is of importance for assessment of heart state and arrhythmic risk.This review is devoted to comprehensive consideration of RH phenomena in terms of electrophysiological processes underlying RH,cardiac electric field formation during ventricular repolarization,as well as clinical significance of RH and its reflection on ECG parameters.The formation of transmural,apicobasal,left-toright and anterior-posterior gradients of action potential durations and end of repolarization times resulting from the heterogenous distribution of repolarizing ion currents and action potential morphology throughout the heart ventricles,and the different sensitivity of myocardial cells in different ventricular regions to the action of pharmacological agents,temperature,frequency of stimulation,etc.,are being discussed.The review is focused on the fact that RH has different aspects–temporal and spatial,global and local;ECG reflection of various RH aspects and their clinical significance are being discussed.Strategies for comprehensive assessment of ventricular RH using different ECG indices reflecting various RH aspects are presented.
基金Supported by The Ministry of Science and Technology of China, preliminarily-selected project of meridian research of national scaling plan, No. Pre-19-211
文摘AIM: To observe the effect of electroacupuncture (EA) of "Neiguan" (PC6) and "Gongsun" (SP4) on pathological changes of the heart and stomach in rats with acute myocardial ischemia (AMI), and to explore its underlying mechanism. METHODS: Fifty Wistar rats were randomized into control, model, PC6, SP4 and PC6 + SP4 groups (n = 8 each group). An AMI model was established by occlusion of the descending anterior branch (DAB) of the left coronary artery. ECG-ST of cervico-thoracic lead and electrogastrogram (EGG) were recorded. EA was applied to PC6, SP4 and PC6 + SP4 groups, respectively. At the end of experiments, the rats were transcardically perfused with 4% paraformaldehyde, and the heart base myocardium, gastric antrum and duodenum tissues were sampled, sectioned and stained with a reduced form of nicotinamide- adenine dinucleotide phosphate (NADPH)-diaphorase histochemical method for displaying nitric oxide synthase (NOS) activity. RESULTS: After AMI, ECG-ST values elevated. After EA, the elevated ECG-ST values at 20 min in PC6group, at 30 min in PC6 + SP4 and SP4 groups had no significant differences in comparison with their respective basal values before AMI. Following AMI, the amplitude and frequency of slow waves of EGG decreased remarkably (P < 0.05). At 30 min after EA, the mean amplitude and frequency of slow waves of EGG in the three EA groups had no marked differences compared with their individual basal levels and those in the control group. After AMI, the mean integral grey values of NOS-positive product in myocardium, gastric antrum and duodenum tissues in the model group increased remarkably in comparison with the control group, while those in three EA groups were lower than those in the model group. No significant differences were found in ECG-ST and EGG improvement among the three EA groups. However, EA of PC6 had a better effect on ECG-ST and EA of PC4 had a better effect on EGG, respectively. CONCLUSION: EA of PC6, SP4 and PC6 + SP4 can significantly promote the recovery of cardiac and gastric electrical activities after AMI, and up-regulate NOS expression in myocardium, gastric antrum and duodenum tissues.
基金This work was supported in part by grants from National Natural Science Foundation of China(No.30328004,No.30571269)National Institutes of Health(R01 GM66258-01).
文摘Objective To examine the effects of urotensin Ⅱ (UII) on the discharges of neurons in CA1 area of hipp-ocampal slices by using extracellular recording technique. Results (1)In response to the application of UII (0.3 , 3.0, 30.0, 300.0 nmol/L, n=77) into the perfusate for 2 min, the spontaneous discharge rates (SDR) of 63/77 (81.8%) neurons were significantly decreased in a dose-dependent manner. (2)Pretreatment with bicuculline(BIC,100μmol/L) , a specific GABAA receptor antagonist, led to a marked increase in the SDR of 6/7 (85.71% ) neurons in an epileptiform pattern. The increased discharges were not significantly changed after UII (30.0 nmol/L) was applied into the perfusate for 2 min. (3) Pretreatment with picrotoxin (PIC, 50μmol/L) , a selective blocker of Cl- channel, led to an increase in the SDR of all 8/8(100% ) neurons. The increased discharges were not influenced by the UII (30.0 nmol/L) applied. (4)Application of nitric oxide synthase (NOS) inhibitor NG-nitro-L-arginine methyl ester (L-NAME, 50μmol/L) into the perfusate for 2 min also significantly augmented the SDR of 14/16 (87.5% ) neurons , then UII (30. 0 nmol/L) applied into the perfusate reduced the increased the SDR of all 14/14 ( 100% ) neurons. Conclusion These results suggest that UII may decrease neuronal activity by potentiating GABAA receptor-mediated Cl- current in hippocampal CA1 neurons, and involved with the mediation of nitric oxide.
基金Project supported by the National Natural Science Foundation of China (G2001CB108902 ,2004CB418506)
文摘The inhibitory effect of gadolinium on Sinorhizobium fredii USDA 205 was studied on a global scale using twodimensional gel electrophoresis and MALDI-TOF MS. The results indicated that 22 proteins were significantly affected by 1 mmol · L^-1 Gd^3 + treatment when compared with an untreated control. Among these proteins, nine were up-regulated and thirteen were down-regulated. The differently expressed proteins were classified into 8 functional categories based on their functions, including transporters, proteins for cellular defence, and proteins involved in metabolism.
基金supported by a grant from Wonkwang Institute of Clinical Medicine in 2011
文摘Although electrical stimulation is therapeutically applied for neural regeneration in patients, it remains unclear how electrical stimulation exerts its effects at the molecular level on spinal cord injury (SCI). To identify the signaling pathway involved in electrical stimulation improving the function of injured spinal cord, 21 female Sprague-Dawley rats were randomly assigned to three groups: control (no surgical intervention, n = 6), SCI (SCI only, n = 5), and electrical simulation (ES; SCI induction followed by ES treatment, n = 10). A complete spinal cord transection was performed at the 10^th thoracic level. Electrical stimulation of the injured spinal cord region was applied for 4 hours per day for 7 days. On days 2 and 7 post SCI, the Touch-Test Sensory Evaluators and the Basso-Beattie-Bresnahan locomotor scale were used to evaluate rat sensory and motor function. Somatosensory-evoked potentials of the tibial nerve of a hind paw of the rat were measured to evaluate the electrophysiological function of injured spinal cord. Western blot analysis was performed to measure p38-RhoA and ERK1/2-Bcl-2 pathways related protein levels in the injured spinal cord. Rat sensory and motor functions were similar between SCI and ES groups. Com- pared with the SCI group, in the ES group, the latencies of the somatosensory-evoked potential of the tibial nerve of rats were significantly shortened, the amplitudes were significantly increased, RhoA protein level was significantly decreased, protein gene product 9.5 expression, ERK1/2, p38, and Bcl-2 protein levels in the spinal cord were significantly increased. These data suggest that ES can promote the recovery of electrophysiological function of the injured spinal cord through regulating p38-RhoA and ERK1/2-Bcl-2 pathway-related protein levels in the injured spinal cord.