We created CRISPR-Cas9 knock-out and overexpressing OsbZIP72 transgenic rice plants to gain a better understanding of the role and molecular mechanism of OsbZIP72 gene in stress tolerance,which has remained largely el...We created CRISPR-Cas9 knock-out and overexpressing OsbZIP72 transgenic rice plants to gain a better understanding of the role and molecular mechanism of OsbZIP72 gene in stress tolerance,which has remained largely elusive.OsbZIP72 was expressed and integrated into rice transgenic plant genomes,and the OsbZIP72 transcript in overexpression lines was elicited by salinity,abscisic acid(ABA)and drought stresses.OsbZIP72 overexpressing plants showed higher tolerance to drought and salinity stresses,while knock-out transgenic lines showed higher sensitivity to these stresses.The differentially expressed genes(DEGs)from RNA-sequencing data encompassed several abiotic stress genes,and the functional classification of these DEGs demonstrated the robust transcriptome diversity in OsbZIP72.Yeast one-hybrid,along with luciferase assay,indicated that OsbZIP72 acted as a transcriptional initiator.Remarkably,electrophoresis mobility assay revealed that OsbZIP72 bound directly to the ABAresponsive element in the OsHKT1;1 promoter region and activated its transcription.Overall,our findings revealed that OsbZIP72 can act as a transcriptional modulator with the ability to induce the expression of OsHKT1;1 in response to environmental stress through an ABA-dependent regulatory pathway,indicating that OsbZIP72 can play a crucial role in the ABA-mediated salt and drought tolerance pathway in rice.展开更多
Rice has a preference for uptake of ammonium over nitrate and can use ammonium-N efficiently. Consequently, transporters mediating ammonium uptake have been extensively studied, but nitrate transporters have been larg...Rice has a preference for uptake of ammonium over nitrate and can use ammonium-N efficiently. Consequently, transporters mediating ammonium uptake have been extensively studied, but nitrate transporters have been largely ignored. Recently, some reports have shown that rice also has high capacity to acquire nitrate from growth medium, so understanding the nitrate transport system in rice roots is very important for improving N use efficiency in rice. The present study Identified four putative NRT2 and two putative NAR2 genes that encode components of the high-affinity nitrate transport system (HATS) in the rice (Oryza sativa L. subsp, japonica cv. Nipponbare) genome. OsNRT2.1 and OsNRT2.2 share an Identical coding region sequence, and their deduced proteins are closely related to those from mono-cotyledonous plants. The two NAR2 proteins are closely related to those from mono-cotyledonous plants as well. However, OsNRT2.3 and OsNRT2.4 are more closely related to Arabidopsis NRT2 proteins. Relative quantitative reverse trsnscription-polymerase chain reaction analysis showed that all of the six genes were rapidly upregulated and then downrsgulated in the roots of N-starved rice plants after they were re-supplied with 0.2 mM nitrate, but the response to nitrate differed among gene members. The results from phylogenetic tree, gene structure and expression analysis implied the divergent roles for the Individual members of the rice NRT2 and NAR2 families. High-affinity nitrate influx rates associated with nitrate induction in rice roots were investigated and were found to be regulated by external pH. Compared with the nitrate influx rates at pH 6.5, alkaline pH (pH 8.0) inhibited nitrate influx, and acidic pH (pH 5.0) enhanced the nitrate influx in 1 h nitrate induced roots, but did not significantly affect that in 4 to 8 h nitrate induced roots.展开更多
Nitrate is a major nitrogen (N) source for most crops. Nitrate uptake by root cells is a key step of nitrogen metabolism and has been widely studied at the physiological and molecular levels. Understanding how nitra...Nitrate is a major nitrogen (N) source for most crops. Nitrate uptake by root cells is a key step of nitrogen metabolism and has been widely studied at the physiological and molecular levels. Understanding how nitrate uptake is regulated will help us engineer crops with improved nitrate uptake efficiency. The present study investigated the regulation of the high-affinity nitrate transport system (HATS) by exogenous abscisic acid (ABA) and glutamine (Gin) in wheat (Triticum aestivum L.) roots. Wheat seedlings grown in nutrient solution containing 2 mmol/L nitrate as the only nitrogen source for 2weeks were deprived of N for 4d and were then transferred to nutrient solution containing 50 μmol/L ABA, and 1 mmol/L Gin in the presence or absence of 2 mmol/L nitrate for 0, 0.5, 1, 2, 4, and 8 h. Treated wheat plants were then divided into two groups. One group of plants was used to investigate the mRNA levels of the HATS components NRT2 and NAR2 genes in roots through semi-quantitative RT-PCR approach, and the other set of plants were used to measure high-affinity nitrate influx rates in a nutrient solution containing 0.2 mmol/L ^15N-labeled nitrate. The results showed that exogenous ABA induced the expression of the TaNRT2.1, TaNRT2.2, TaNRT2.3, TaNAR2.1, and TaNAR2.2 genes in roots when nitrate was not present in the nutrient solution, but did not further enhance the induction of these genes by nitrate. Glutamine, which has been shown to inhibit the expression of NRT2 genes when nitrate is present in the growth media, did not inhibit this induction. When Gin was supplied to a nitrate-free nutrient solution, the expression of these five genes in roots was induced. These results imply that the inhibition by Gin of NRT2 expression occurs only when nitrate is present in the growth media. Although exogenous ABA and Gin induced HATS genes in the roots of wheat, they did not induce nitrate influx.展开更多
Cytokine-activated T cells (CATs) can be easily expanded and are widely applied to cancer immunotherapy. However, the good efficacy of CATs is rarely reported in clinical applications because CATs have no or very low ...Cytokine-activated T cells (CATs) can be easily expanded and are widely applied to cancer immunotherapy. However, the good efficacy of CATs is rarely reported in clinical applications because CATs have no or very low antigen specificity. The low-efficacy problem can be resolved using T cell antigen receptorengineered CAT (TCR-CAT). Herein, we demonstrate that NY-ESO-1157-165 HLA-A*02:01-specific high-affinity TCR (HAT)-transduced CATs can specifically kill cancer cells with good efficacy. With low micromolar range dissociation equilibrium constants, HAT-transduced CATs showed good specificity with no off-target killing. Furthermore, the high-affinity TCR-CATs delivered significantly better activation and cytotoxicity than the equivalent TCR-engineered T cells (TCR-Ts) in terms of interferon-γ and granzyme B production and in vitro cancer cell killing ability. TCR-CAT may be a very good alternative to the expensive TCR-T, which is considered an effective personalized cyto-immunotherapy.展开更多
To verify the feasibility of high-affinity nitrate transporter gene (Nrt2) as an indicator of nitrogen status, changes in the transcript levels of transcripts associated with phosphate starvation and different nitra...To verify the feasibility of high-affinity nitrate transporter gene (Nrt2) as an indicator of nitrogen status, changes in the transcript levels of transcripts associated with phosphate starvation and different nitrate concentrations were studied using real-time quantitative reverse-transcription PCR (QRT-PCR) technology in batch cultures of Skeletonema costatum. The results show that compared with P-replete condition, P starvation could reduce the Nrt2 transcript levels apparently. Nrt2 transcript levels had a significant negative linear correlation with nitrate concentrations below 40 pmol/L. The results of 48 h short-term incubation experiment under different nitrate concentrations confirmed this correlation, and the following regression equation is built: y = -3.305x + 98.95, R2 = 0.988, where x represents nitrate concentrations (〈40 btmol/L) and y represents the Nrt2 transcript levels.展开更多
Molecular recognition in water,the biological solvent,always receives significant research focus in supramolecular chemistry.The mechanisms of molecular recognition in water is key to comprehending biological processe...Molecular recognition in water,the biological solvent,always receives significant research focus in supramolecular chemistry.The mechanisms of molecular recognition in water is key to comprehending biological processes at the molecular level.Over the past five decades,supramolecular chemists have developed a vast array of synthetic receptors with highly diverse structures and recognition properties.Among them,cyclophanes represent an important family of macrocyclic receptors that have been extensively explored.The aromatic moieties in cyclophanes not only facilitate chemical modifications to impart water solubility but also enable forming hydrophobic cavities for guest inclusion in aqueous environments.Pioneered by Koga et al.,who reported the first inclusion complex of cyclophanes in water and solid state,numerous water-soluble cyclophanes,including derivatives of blue box,calixarenes,resorcinarenes,pillararenes,octopusarenes,biphenarenes,coronarenes,and naphthotubes,etc.,have been synthesized and subjected to investigation of the recognition capabilities in aqueous solutions.This review provides an overview of cyclophane receptors designed to bind organic guests in water.We categorize them into two classes based on the modifications made to their hydrophobic cavities:those with“exo-functionalized hydrophobic cavities”and those with“endo-functionalized hydrophobic cavities”.We introduce their distinctive features and discuss strategies to enhance recognition affinity and selectivity.This review aims to inspire the development of novel synthetic receptors with intriguing properties and foster practical applications of cyclophanes.展开更多
In halophytic plants, the high-affinity potassium transporter HKT gene family can selectively uptake K+ in the presence of toxic concentrations of Na+. This has so far not been well examined in glycophytic crops. He...In halophytic plants, the high-affinity potassium transporter HKT gene family can selectively uptake K+ in the presence of toxic concentrations of Na+. This has so far not been well examined in glycophytic crops. Here, we report the characterization of SbHKTI;4, a member of the HKT gene family from Sorghum bicolor. Upon Na+ stress, SbHKT1;4 expression was more strongly upregulated in salt-tolerant sorghum accession, correlating with a better balanced Na+/ K+ ratio and enhanced plant growth. Heterogeneous expression analyses in mutants of Saccharomyces cerevisiae and Arabidopsis thaliana indicated that overexpressing SbHKT1;4 resulted in hypersensitivity to Na+ stress, and such hypersensitivity could be alleviated with the supply of elevated levels of K+, implicating that SbHKT1;4 may mediate K+ uptake in the presence of excessive Na+. Further electrophysiological evidence demonstrated that SbHKT1;4 could transport Na+ and K+ when expressed in Xenopus laevis oocytes. The relevance of the finding that SbHKTI;4 functions to maintain optimal Na+/K+ balance under Na+ stress to the breeding of salt-tolerant glycophytic crops is discussed.展开更多
TaPHT1.2 is a functional, root predominantly expressed and low phosphate (Pi) inducible high-affinity Pi transporter in wheat, which is more abundant in the roots of P-efficient wheat genotypes (e.g., Xiaoyan 54) ...TaPHT1.2 is a functional, root predominantly expressed and low phosphate (Pi) inducible high-affinity Pi transporter in wheat, which is more abundant in the roots of P-efficient wheat genotypes (e.g., Xiaoyan 54) than in P-inefficient genotypes (e.g., Jing 411) under both Pi-deficient and Pi-sufficient conditions. To characterize TaPHT1.2 further, we genetically mapped a TaPHT1.2 transporter, TaPHT1.2-D1, on the long arm of chromosome 4D using a recombinant inbred line population derived from Xiaoyan 54 and Jing 411, and isolated a 1,302 bp fragment of the TaPHT1.2-D1 promoter (PrTaPHT1.2-D1) from Xiaoyan 54. TaPHT1.2-D1 shows collinearity with OsPHT1.2 that has previously been reported to mediate the translocation of Pi from roots to shoots. PrTaPHT1.2-D contains a number of Pi-starvation responsive elements, including P1BS, WRKY-binding W-box, and helix-loop-helix-binding elements. PrTaPHT1.2-D1 was then used to drive expression of 13-glucuronidase (GUS) reporter gene in Arabidopsis through Agrobacterium-mediated transformation. Histochemical analysis of transgenic Arabidopsis plants showed that the reporter gene was specifically induced by Pi-starvation and predominantly expressed in the roots. As there is only one SNP between the TaPHT1.2-D1 promoters of Xiaoyan 54 and Jing 411, and this SNP does not exist within the Pi-starvation responsive elements, the differential expression of TaPHT1.2 in Xiaoyan 54 and Jing 411 may not be caused by this SNP.展开更多
OsPT6:1,a phosphate transporter encoding gene from the leaf samples of Oryza sativa, was identified through PCR with specifically designed primers.The phylogenetic analysis and the conserved amino acid residue site de...OsPT6:1,a phosphate transporter encoding gene from the leaf samples of Oryza sativa, was identified through PCR with specifically designed primers.The phylogenetic analysis and the conserved amino acid residue site detection suggested OsPT6:1 a possible high-affinity phosphate transporter encoding gene.In situ hybridization and RT-PCR demonstrated the expression of OsPT6:1 in both roots and leaves.The peak expression signal was observed in mesophyll cells under low phosphorus(P)induction.A homologous recombination study indicated that OsPT6:1 can enhance the Pi uptake efficiency of Pichia pastoris.At the meantime,the introduction of OsPT6:1 was able to complement the Pi uptake function of yeast cells with high-affinity phosphate transporters de- ficient.Those results substantiated our contention that OsPT6:1 encoded a high-affinity phosphate transporter of Oryza sativa.展开更多
Mucormycosis is a lethal human disease caused by fungi of the order Mucorales.Mucormycosis is caused by fungi mainly belonging to the genera Mucor,Rhizopus,and Lichtheimia,all of which belong to the order Mucorales.Th...Mucormycosis is a lethal human disease caused by fungi of the order Mucorales.Mucormycosis is caused by fungi mainly belonging to the genera Mucor,Rhizopus,and Lichtheimia,all of which belong to the order Mucorales.The number of individuals with mucormycosis-causing disorders has increased in recent years,hence,leading to the spread of mucormycosis.Throughout the coronavirus disease 2019(COVID-19)pandemic,numerous cases of mucormycosis in COVID-19-infected patients have been reported worldwide,and the illness is now recognized as COVID-19-associated mucormycosis,with most of the cases being reported from India.Immunocompromised patients such as those with bone marrow sickness and uncontrolled diabetes are at a greater risk of developing mucormycosis.Genes,pathways,and other mechanisms have been studied in Mucorales,demonstrating a direct link between virulence and prospective therapeutic and diagnostic targets.This review discusses several proteins such as high-affinity iron permease(FTR1),calcineurin,spore coat protein(CotH),and ADP-ribosylation factors involved in the pathogenesis of mucormycosis that might prove to be viable target(s)for the development of novel diagnostic and therapeutic methods.展开更多
Objective To investigate the link between the polymorphism of -109 and Glu237 in the high-affinity IgE receptor β (FcεRⅠβ) gene and susceptibilty to allergic asthma in a Chinese population.Method Blood samples fro...Objective To investigate the link between the polymorphism of -109 and Glu237 in the high-affinity IgE receptor β (FcεRⅠβ) gene and susceptibilty to allergic asthma in a Chinese population.Method Blood samples from 216 allergic asthma patients and 198 age- and sex-matched controls were studied. A-109C/T and a coding variant Glu237Gly in FcεRⅠβ were detected with polymerase chain reaction-restriction fragment length polymorphism(PCR-RFLP). Results The genotype frequencies were 0.403 for -109T/T, 0.491 for -109T/C and 0.106 for -109C/C in allergic asthma in a Chinese population. No significant difference in the distribution of -109C/T polymorphism was found between allergic asthma subjects and healthy controls, however, homozygosity for the -109T allele was associated with increased total plasma IgE levels in subjects with allergic asthma (F=4.020,P<0.05). The allele frequency of Gly237 in the patients and control was 0.236 and 0.136 respectively. There was a significant association between the Gly/Gly genotype and allergic asthma. Among allergic asthma patients Gly237 was significantly associated with high IgE levels.Conclusions These results suggest that the Gly237 variant of the FcεRⅠβ gene is involved in the development of allergic asthma. The-109C/T and Glu237Gly polymorphisms are two of the genetic factor identified thus far, which affect total plasma IgE levels of allergic asthma patients in a Chinese population.展开更多
基金supported by the earmarked funds for China Agriculture Research System(Grant No.CARS-01-61)National Science and Technology Support Program of China(Grant No.2015BAD01B01)+3 种基金Science and Technology Support Program of Jiangsu Province,China(Grant Nos.BE2016370-3 and BE2017323)the Natural Science Foundation of Jiangsu Province,China(Grant No.BK20161299)the Financial Grant Support Program of Lianyungang City,Jiangsu Province,China(Grant Nos.QNJJ1704 and QNJJ1912)National Natural Science Foundation of China(Grant No.31701395).
文摘We created CRISPR-Cas9 knock-out and overexpressing OsbZIP72 transgenic rice plants to gain a better understanding of the role and molecular mechanism of OsbZIP72 gene in stress tolerance,which has remained largely elusive.OsbZIP72 was expressed and integrated into rice transgenic plant genomes,and the OsbZIP72 transcript in overexpression lines was elicited by salinity,abscisic acid(ABA)and drought stresses.OsbZIP72 overexpressing plants showed higher tolerance to drought and salinity stresses,while knock-out transgenic lines showed higher sensitivity to these stresses.The differentially expressed genes(DEGs)from RNA-sequencing data encompassed several abiotic stress genes,and the functional classification of these DEGs demonstrated the robust transcriptome diversity in OsbZIP72.Yeast one-hybrid,along with luciferase assay,indicated that OsbZIP72 acted as a transcriptional initiator.Remarkably,electrophoresis mobility assay revealed that OsbZIP72 bound directly to the ABAresponsive element in the OsHKT1;1 promoter region and activated its transcription.Overall,our findings revealed that OsbZIP72 can act as a transcriptional modulator with the ability to induce the expression of OsHKT1;1 in response to environmental stress through an ABA-dependent regulatory pathway,indicating that OsbZIP72 can play a crucial role in the ABA-mediated salt and drought tolerance pathway in rice.
基金the National Natural Science Foundation of China (30390080and 30521001)the Ministry of Science and Technology of China(2005CB120900 and 2004CB117200)
文摘Rice has a preference for uptake of ammonium over nitrate and can use ammonium-N efficiently. Consequently, transporters mediating ammonium uptake have been extensively studied, but nitrate transporters have been largely ignored. Recently, some reports have shown that rice also has high capacity to acquire nitrate from growth medium, so understanding the nitrate transport system in rice roots is very important for improving N use efficiency in rice. The present study Identified four putative NRT2 and two putative NAR2 genes that encode components of the high-affinity nitrate transport system (HATS) in the rice (Oryza sativa L. subsp, japonica cv. Nipponbare) genome. OsNRT2.1 and OsNRT2.2 share an Identical coding region sequence, and their deduced proteins are closely related to those from mono-cotyledonous plants. The two NAR2 proteins are closely related to those from mono-cotyledonous plants as well. However, OsNRT2.3 and OsNRT2.4 are more closely related to Arabidopsis NRT2 proteins. Relative quantitative reverse trsnscription-polymerase chain reaction analysis showed that all of the six genes were rapidly upregulated and then downrsgulated in the roots of N-starved rice plants after they were re-supplied with 0.2 mM nitrate, but the response to nitrate differed among gene members. The results from phylogenetic tree, gene structure and expression analysis implied the divergent roles for the Individual members of the rice NRT2 and NAR2 families. High-affinity nitrate influx rates associated with nitrate induction in rice roots were investigated and were found to be regulated by external pH. Compared with the nitrate influx rates at pH 6.5, alkaline pH (pH 8.0) inhibited nitrate influx, and acidic pH (pH 5.0) enhanced the nitrate influx in 1 h nitrate induced roots, but did not significantly affect that in 4 to 8 h nitrate induced roots.
基金Supported by the National Natural Science Foundation of China(30390083 and 30521001)the State Key Basic Research and Development Plan of China(2005CB120904 and 2004CB117200)
文摘Nitrate is a major nitrogen (N) source for most crops. Nitrate uptake by root cells is a key step of nitrogen metabolism and has been widely studied at the physiological and molecular levels. Understanding how nitrate uptake is regulated will help us engineer crops with improved nitrate uptake efficiency. The present study investigated the regulation of the high-affinity nitrate transport system (HATS) by exogenous abscisic acid (ABA) and glutamine (Gin) in wheat (Triticum aestivum L.) roots. Wheat seedlings grown in nutrient solution containing 2 mmol/L nitrate as the only nitrogen source for 2weeks were deprived of N for 4d and were then transferred to nutrient solution containing 50 μmol/L ABA, and 1 mmol/L Gin in the presence or absence of 2 mmol/L nitrate for 0, 0.5, 1, 2, 4, and 8 h. Treated wheat plants were then divided into two groups. One group of plants was used to investigate the mRNA levels of the HATS components NRT2 and NAR2 genes in roots through semi-quantitative RT-PCR approach, and the other set of plants were used to measure high-affinity nitrate influx rates in a nutrient solution containing 0.2 mmol/L ^15N-labeled nitrate. The results showed that exogenous ABA induced the expression of the TaNRT2.1, TaNRT2.2, TaNRT2.3, TaNAR2.1, and TaNAR2.2 genes in roots when nitrate was not present in the nutrient solution, but did not further enhance the induction of these genes by nitrate. Glutamine, which has been shown to inhibit the expression of NRT2 genes when nitrate is present in the growth media, did not inhibit this induction. When Gin was supplied to a nitrate-free nutrient solution, the expression of these five genes in roots was induced. These results imply that the inhibition by Gin of NRT2 expression occurs only when nitrate is present in the growth media. Although exogenous ABA and Gin induced HATS genes in the roots of wheat, they did not induce nitrate influx.
文摘Cytokine-activated T cells (CATs) can be easily expanded and are widely applied to cancer immunotherapy. However, the good efficacy of CATs is rarely reported in clinical applications because CATs have no or very low antigen specificity. The low-efficacy problem can be resolved using T cell antigen receptorengineered CAT (TCR-CAT). Herein, we demonstrate that NY-ESO-1157-165 HLA-A*02:01-specific high-affinity TCR (HAT)-transduced CATs can specifically kill cancer cells with good efficacy. With low micromolar range dissociation equilibrium constants, HAT-transduced CATs showed good specificity with no off-target killing. Furthermore, the high-affinity TCR-CATs delivered significantly better activation and cytotoxicity than the equivalent TCR-engineered T cells (TCR-Ts) in terms of interferon-γ and granzyme B production and in vitro cancer cell killing ability. TCR-CAT may be a very good alternative to the expensive TCR-T, which is considered an effective personalized cyto-immunotherapy.
基金The National Basic Research Program of China(973Program)under contract No.2010CB428706the National Natural Science Foundation of China for Creative Research Groups under contract No.41121064the National High Technology Research and Development Program of China under contract No.2008AA09Z107
文摘To verify the feasibility of high-affinity nitrate transporter gene (Nrt2) as an indicator of nitrogen status, changes in the transcript levels of transcripts associated with phosphate starvation and different nitrate concentrations were studied using real-time quantitative reverse-transcription PCR (QRT-PCR) technology in batch cultures of Skeletonema costatum. The results show that compared with P-replete condition, P starvation could reduce the Nrt2 transcript levels apparently. Nrt2 transcript levels had a significant negative linear correlation with nitrate concentrations below 40 pmol/L. The results of 48 h short-term incubation experiment under different nitrate concentrations confirmed this correlation, and the following regression equation is built: y = -3.305x + 98.95, R2 = 0.988, where x represents nitrate concentrations (〈40 btmol/L) and y represents the Nrt2 transcript levels.
基金supported by the National Natural Science Foundation of China(Nos.22271164,U20A20259)the Fundamental Research Funds for the Central Universitiesthe NCC Fund(No.NCC2020FH04).
文摘Molecular recognition in water,the biological solvent,always receives significant research focus in supramolecular chemistry.The mechanisms of molecular recognition in water is key to comprehending biological processes at the molecular level.Over the past five decades,supramolecular chemists have developed a vast array of synthetic receptors with highly diverse structures and recognition properties.Among them,cyclophanes represent an important family of macrocyclic receptors that have been extensively explored.The aromatic moieties in cyclophanes not only facilitate chemical modifications to impart water solubility but also enable forming hydrophobic cavities for guest inclusion in aqueous environments.Pioneered by Koga et al.,who reported the first inclusion complex of cyclophanes in water and solid state,numerous water-soluble cyclophanes,including derivatives of blue box,calixarenes,resorcinarenes,pillararenes,octopusarenes,biphenarenes,coronarenes,and naphthotubes,etc.,have been synthesized and subjected to investigation of the recognition capabilities in aqueous solutions.This review provides an overview of cyclophane receptors designed to bind organic guests in water.We categorize them into two classes based on the modifications made to their hydrophobic cavities:those with“exo-functionalized hydrophobic cavities”and those with“endo-functionalized hydrophobic cavities”.We introduce their distinctive features and discuss strategies to enhance recognition affinity and selectivity.This review aims to inspire the development of novel synthetic receptors with intriguing properties and foster practical applications of cyclophanes.
基金supported by the "One Hundred Talents" Program of the Chinese Academy of Sciences (KSCX2‐YW‐G‐067)the National Science Foundation grant (Y4643A1001)
文摘In halophytic plants, the high-affinity potassium transporter HKT gene family can selectively uptake K+ in the presence of toxic concentrations of Na+. This has so far not been well examined in glycophytic crops. Here, we report the characterization of SbHKTI;4, a member of the HKT gene family from Sorghum bicolor. Upon Na+ stress, SbHKT1;4 expression was more strongly upregulated in salt-tolerant sorghum accession, correlating with a better balanced Na+/ K+ ratio and enhanced plant growth. Heterogeneous expression analyses in mutants of Saccharomyces cerevisiae and Arabidopsis thaliana indicated that overexpressing SbHKT1;4 resulted in hypersensitivity to Na+ stress, and such hypersensitivity could be alleviated with the supply of elevated levels of K+, implicating that SbHKT1;4 may mediate K+ uptake in the presence of excessive Na+. Further electrophysiological evidence demonstrated that SbHKT1;4 could transport Na+ and K+ when expressed in Xenopus laevis oocytes. The relevance of the finding that SbHKTI;4 functions to maintain optimal Na+/K+ balance under Na+ stress to the breeding of salt-tolerant glycophytic crops is discussed.
基金supported by the Ministry of Science and Technology of China (No.2005CB120904 and 2006AA10A105)the National Natural Science Foundation of China (No.30890133 and 30521001)the Chinese Academy of Sciences (No.KSCX2-YW-N-001)
文摘TaPHT1.2 is a functional, root predominantly expressed and low phosphate (Pi) inducible high-affinity Pi transporter in wheat, which is more abundant in the roots of P-efficient wheat genotypes (e.g., Xiaoyan 54) than in P-inefficient genotypes (e.g., Jing 411) under both Pi-deficient and Pi-sufficient conditions. To characterize TaPHT1.2 further, we genetically mapped a TaPHT1.2 transporter, TaPHT1.2-D1, on the long arm of chromosome 4D using a recombinant inbred line population derived from Xiaoyan 54 and Jing 411, and isolated a 1,302 bp fragment of the TaPHT1.2-D1 promoter (PrTaPHT1.2-D1) from Xiaoyan 54. TaPHT1.2-D1 shows collinearity with OsPHT1.2 that has previously been reported to mediate the translocation of Pi from roots to shoots. PrTaPHT1.2-D contains a number of Pi-starvation responsive elements, including P1BS, WRKY-binding W-box, and helix-loop-helix-binding elements. PrTaPHT1.2-D1 was then used to drive expression of 13-glucuronidase (GUS) reporter gene in Arabidopsis through Agrobacterium-mediated transformation. Histochemical analysis of transgenic Arabidopsis plants showed that the reporter gene was specifically induced by Pi-starvation and predominantly expressed in the roots. As there is only one SNP between the TaPHT1.2-D1 promoters of Xiaoyan 54 and Jing 411, and this SNP does not exist within the Pi-starvation responsive elements, the differential expression of TaPHT1.2 in Xiaoyan 54 and Jing 411 may not be caused by this SNP.
基金supported by the National Natural Science Foundation of China(Grant No.30300193)the Youth Science and Technology Phosphor Foundation of Shanghai(Grant No.05QMX1408)Excellent Young Teacher in Support Candidates of Shanghai Universities(Grant No.04YQHB006).
文摘OsPT6:1,a phosphate transporter encoding gene from the leaf samples of Oryza sativa, was identified through PCR with specifically designed primers.The phylogenetic analysis and the conserved amino acid residue site detection suggested OsPT6:1 a possible high-affinity phosphate transporter encoding gene.In situ hybridization and RT-PCR demonstrated the expression of OsPT6:1 in both roots and leaves.The peak expression signal was observed in mesophyll cells under low phosphorus(P)induction.A homologous recombination study indicated that OsPT6:1 can enhance the Pi uptake efficiency of Pichia pastoris.At the meantime,the introduction of OsPT6:1 was able to complement the Pi uptake function of yeast cells with high-affinity phosphate transporters de- ficient.Those results substantiated our contention that OsPT6:1 encoded a high-affinity phosphate transporter of Oryza sativa.
文摘Mucormycosis is a lethal human disease caused by fungi of the order Mucorales.Mucormycosis is caused by fungi mainly belonging to the genera Mucor,Rhizopus,and Lichtheimia,all of which belong to the order Mucorales.The number of individuals with mucormycosis-causing disorders has increased in recent years,hence,leading to the spread of mucormycosis.Throughout the coronavirus disease 2019(COVID-19)pandemic,numerous cases of mucormycosis in COVID-19-infected patients have been reported worldwide,and the illness is now recognized as COVID-19-associated mucormycosis,with most of the cases being reported from India.Immunocompromised patients such as those with bone marrow sickness and uncontrolled diabetes are at a greater risk of developing mucormycosis.Genes,pathways,and other mechanisms have been studied in Mucorales,demonstrating a direct link between virulence and prospective therapeutic and diagnostic targets.This review discusses several proteins such as high-affinity iron permease(FTR1),calcineurin,spore coat protein(CotH),and ADP-ribosylation factors involved in the pathogenesis of mucormycosis that might prove to be viable target(s)for the development of novel diagnostic and therapeutic methods.
基金ThisprojectwassupportedbyagrantfromtheNationalNaturalScienceFoundationofChina (No 3 0 10 0 169)
文摘Objective To investigate the link between the polymorphism of -109 and Glu237 in the high-affinity IgE receptor β (FcεRⅠβ) gene and susceptibilty to allergic asthma in a Chinese population.Method Blood samples from 216 allergic asthma patients and 198 age- and sex-matched controls were studied. A-109C/T and a coding variant Glu237Gly in FcεRⅠβ were detected with polymerase chain reaction-restriction fragment length polymorphism(PCR-RFLP). Results The genotype frequencies were 0.403 for -109T/T, 0.491 for -109T/C and 0.106 for -109C/C in allergic asthma in a Chinese population. No significant difference in the distribution of -109C/T polymorphism was found between allergic asthma subjects and healthy controls, however, homozygosity for the -109T allele was associated with increased total plasma IgE levels in subjects with allergic asthma (F=4.020,P<0.05). The allele frequency of Gly237 in the patients and control was 0.236 and 0.136 respectively. There was a significant association between the Gly/Gly genotype and allergic asthma. Among allergic asthma patients Gly237 was significantly associated with high IgE levels.Conclusions These results suggest that the Gly237 variant of the FcεRⅠβ gene is involved in the development of allergic asthma. The-109C/T and Glu237Gly polymorphisms are two of the genetic factor identified thus far, which affect total plasma IgE levels of allergic asthma patients in a Chinese population.