Understanding how maize(Zea mays)responds to cold stress is crucial for facilitating breeding programs of cold-tolerant varieties.Despite extensive utilization of the genome-wide association study(GWAs)approach for ex...Understanding how maize(Zea mays)responds to cold stress is crucial for facilitating breeding programs of cold-tolerant varieties.Despite extensive utilization of the genome-wide association study(GWAs)approach for exploring favorable natural alleles associated with maize cold tolerance,few studies have successfully identified candidate genes that contribute to maize cold tolerance.In this study,we used a diverse panel of inbred maize lines collected from different germplasm sources to perform a GWAS on var-iations in the relative injured area of maize true leaves during cold stress-a trait very closely correlated with maize cold tolerance.We identified HsF21,which encodes a B-class heat shock transcription factor(HSF)that positively regulates cold tolerance at both the seedling and germination stages.Natural varia-tions in the promoter of the cold-tolerant HSF21Hap1 allele led to increased HSF21 expression under cold stress by inhibiting binding of the basic leucine zipper bziP68 transcription factor,a negative regulator of cold tolerance.By integrating transcriptome deep sequencing,DNA affinity purification sequencing,and targeted lipidomic analysis,we revealed the function of HsF21 in regulating lipid metabolism homeo-stasis to modulate cold tolerance in maize.In addition,we found that HsF21 confers maize cold tolerance without incurring yield penalties.Collectively,this study establishes HsF21 as a key regulator that en-hances cold tolerance in maize,providing valuable genetic resources for breeding of cold-tolerant maize varieties.展开更多
基金supported by Biological Breeding-National Science and Technology Major Project of China(2023ZD0407104)the National Natural Science Foundation of China(32272025 and 31730011)the Pinduoduo-China Agricultural University Research Fund(PC2023B01001),and the Chinese Universities Scientific Fund.
文摘Understanding how maize(Zea mays)responds to cold stress is crucial for facilitating breeding programs of cold-tolerant varieties.Despite extensive utilization of the genome-wide association study(GWAs)approach for exploring favorable natural alleles associated with maize cold tolerance,few studies have successfully identified candidate genes that contribute to maize cold tolerance.In this study,we used a diverse panel of inbred maize lines collected from different germplasm sources to perform a GWAS on var-iations in the relative injured area of maize true leaves during cold stress-a trait very closely correlated with maize cold tolerance.We identified HsF21,which encodes a B-class heat shock transcription factor(HSF)that positively regulates cold tolerance at both the seedling and germination stages.Natural varia-tions in the promoter of the cold-tolerant HSF21Hap1 allele led to increased HSF21 expression under cold stress by inhibiting binding of the basic leucine zipper bziP68 transcription factor,a negative regulator of cold tolerance.By integrating transcriptome deep sequencing,DNA affinity purification sequencing,and targeted lipidomic analysis,we revealed the function of HsF21 in regulating lipid metabolism homeo-stasis to modulate cold tolerance in maize.In addition,we found that HsF21 confers maize cold tolerance without incurring yield penalties.Collectively,this study establishes HsF21 as a key regulator that en-hances cold tolerance in maize,providing valuable genetic resources for breeding of cold-tolerant maize varieties.
