Drought is one of the most important abiotic stresses affecting maize growth and development and therefore resulting in yield loss.Thus it is essential to understand molecular mechanisms of drought stress responses in...Drought is one of the most important abiotic stresses affecting maize growth and development and therefore resulting in yield loss.Thus it is essential to understand molecular mechanisms of drought stress responses in maize for drought tolerance improvement.The root plays a critical role in plants sensing water deficit.In the present study,two maize inbred lines,H082183,a drought-tolerant line,and Lv28,a drought-sensitive line,were grown in the field and treated with different water conditions(moderate drought,severe drought,and well-watered conditions)during vegetative stage.The transcriptomes of their roots were investigated by RNA sequencing.There were 1428 and 512 drought-responsive genes(DRGs)in Lv28,688 and 3363 DRGs in H082183 under moderate drought and severe drought,respectively.A total of 31 Gene Ontology(GO)terms were significantly over-represented in the two lines,13 of which were enriched only in the DRGs of H082183.Based on results of Kyoto encyclopedia of genes and genomes(KEGG)enrichment analysis,"plant hormone signal transduction"and"starch and sucrose metabolism"were enriched in both of the two lines,while"phenylpropanoid biosynthesis"was only enriched in H082183.Further analysis revealed the different expression patterns of genes related to abscisic acid(ABA)signal pathway,trehalose biosynthesis,reactive oxygen scavenging,and transcription factors might contribute to drought tolerance in maize.Our results contribute to illustrating drought-responsive molecular mechanisms and providing gene resources for maize drought improvement.展开更多
Plants orchestrate drought responses at metabolic level but the genetic basis remains elusive in rice.In this study,233 drought-responsive metabolites(DRMs)were quantified in a large rice population comprised of 510 d...Plants orchestrate drought responses at metabolic level but the genetic basis remains elusive in rice.In this study,233 drought-responsive metabolites(DRMs)were quantified in a large rice population comprised of 510 diverse accessions at the reproductive stage.Large metabolic variations in drought responses were detected,and little correlation of metabolic levels between drought and normal conditions were observed.Interestingly,most of these DRMs could predict drought resistance in high accuracy.Genome-wide association study revealed 2522 significant association signals for 233 DRMs,and 98%(2471/2522)of the signals were co-localized with the association loci for droughtrelated phenotypic traits in the same population or the linkage-mapped QTLs for drought resistance in other populations.Totally,10 candidate genes were efficiently identified for nine DRMs,seven of which harbored cis-eQTLs under drought condition.Based on comparative GWAS of common DRMs in rice and maize,representing irrigated and upland crops,we have identified three pairs of homologous genes associated with three DRMs between the two crops.Among the homologous genes,a transferase gene responsible for metabolic variation of N-feruloylputrescine was confirmed to confer enhanced drought resistance in rice.Our study provides not only genetic architecture of metabolic responses to drought stress in rice but also metabolic data resources to reveal the common and specific metabolite-mediated drought responses in different crops.展开更多
基金supported by the Sci-Tech Innovation Program of Chinese Academy of Agricultural Sciences (Y2016PT10)
文摘Drought is one of the most important abiotic stresses affecting maize growth and development and therefore resulting in yield loss.Thus it is essential to understand molecular mechanisms of drought stress responses in maize for drought tolerance improvement.The root plays a critical role in plants sensing water deficit.In the present study,two maize inbred lines,H082183,a drought-tolerant line,and Lv28,a drought-sensitive line,were grown in the field and treated with different water conditions(moderate drought,severe drought,and well-watered conditions)during vegetative stage.The transcriptomes of their roots were investigated by RNA sequencing.There were 1428 and 512 drought-responsive genes(DRGs)in Lv28,688 and 3363 DRGs in H082183 under moderate drought and severe drought,respectively.A total of 31 Gene Ontology(GO)terms were significantly over-represented in the two lines,13 of which were enriched only in the DRGs of H082183.Based on results of Kyoto encyclopedia of genes and genomes(KEGG)enrichment analysis,"plant hormone signal transduction"and"starch and sucrose metabolism"were enriched in both of the two lines,while"phenylpropanoid biosynthesis"was only enriched in H082183.Further analysis revealed the different expression patterns of genes related to abscisic acid(ABA)signal pathway,trehalose biosynthesis,reactive oxygen scavenging,and transcription factors might contribute to drought tolerance in maize.Our results contribute to illustrating drought-responsive molecular mechanisms and providing gene resources for maize drought improvement.
文摘Plants orchestrate drought responses at metabolic level but the genetic basis remains elusive in rice.In this study,233 drought-responsive metabolites(DRMs)were quantified in a large rice population comprised of 510 diverse accessions at the reproductive stage.Large metabolic variations in drought responses were detected,and little correlation of metabolic levels between drought and normal conditions were observed.Interestingly,most of these DRMs could predict drought resistance in high accuracy.Genome-wide association study revealed 2522 significant association signals for 233 DRMs,and 98%(2471/2522)of the signals were co-localized with the association loci for droughtrelated phenotypic traits in the same population or the linkage-mapped QTLs for drought resistance in other populations.Totally,10 candidate genes were efficiently identified for nine DRMs,seven of which harbored cis-eQTLs under drought condition.Based on comparative GWAS of common DRMs in rice and maize,representing irrigated and upland crops,we have identified three pairs of homologous genes associated with three DRMs between the two crops.Among the homologous genes,a transferase gene responsible for metabolic variation of N-feruloylputrescine was confirmed to confer enhanced drought resistance in rice.Our study provides not only genetic architecture of metabolic responses to drought stress in rice but also metabolic data resources to reveal the common and specific metabolite-mediated drought responses in different crops.
