The awn can contribute to photosynthesis and carbohydrates,enhancing grain yield in wheat.We mapped QAwn.sxau-5A,a major QTL for awn development in wheat(Triticum aestivum).This QTL was delimited to a 994-kb interval ...The awn can contribute to photosynthesis and carbohydrates,enhancing grain yield in wheat.We mapped QAwn.sxau-5A,a major QTL for awn development in wheat(Triticum aestivum).This QTL was delimited to a 994-kb interval at the B1 locus on chromosome 5A,which included the candidate gene encoding a zinc finger protein(TraesCS5A01G542800)as an awn length inhibitor(ALI).The Ali-A1 allele for the awnless trait showed abundant sequence differences in the promoter regions compared to the ali-A1 allele for the long-awn trait.The results of the swap experiment on the promoters from the two ALI-A1 alleles showed that the two promoters caused a difference in the protein level,indicating the gene was regulated at the transcript level.However,the ali-A1 allele contained an SNP that caused a premature stop codon in its coding region,resulting in a truncated protein compared to the functional Ali-A1 protein.The Ali-A1 protein contained two ethylene-responsive element binding factor-associated amphiphilic repression(EAR)motifs,one at the N terminus(EAR-N)and the other at the C terminus(EAR-C),and they were involved in interactions with the wheat co-repressor protein TOPLESS(TPL1).The ali-A1 protein retained the EAR-N motif but lost the EAR-C motif,resulting in the attenuated ability to interact with TPL1.The tpl1 mutant produced a longer awn compared to the wild type.Ali-A1 repressed the transcription of two downstream genes,TaLRP-A1 and TaARF-B1,involved in endogenous auxin concentrations and auxin responses in wheat.We concluded that the awn length is regulated not only by the ALI-A1 gene at transcript levels but also by Ali-A1 and TPL1 at the protein level in wheat.展开更多
基金supported by the Grand Science and Technology Special Project in Shanxi Province(202201140601025-2)the National Natural Science Foundation of China(32201749)supported by the Agriculture and Food Research Initiative Competitive Grant 2022-68013-36439(WheatCAP)from the USDA National Institute of Food and Agriculture.
文摘The awn can contribute to photosynthesis and carbohydrates,enhancing grain yield in wheat.We mapped QAwn.sxau-5A,a major QTL for awn development in wheat(Triticum aestivum).This QTL was delimited to a 994-kb interval at the B1 locus on chromosome 5A,which included the candidate gene encoding a zinc finger protein(TraesCS5A01G542800)as an awn length inhibitor(ALI).The Ali-A1 allele for the awnless trait showed abundant sequence differences in the promoter regions compared to the ali-A1 allele for the long-awn trait.The results of the swap experiment on the promoters from the two ALI-A1 alleles showed that the two promoters caused a difference in the protein level,indicating the gene was regulated at the transcript level.However,the ali-A1 allele contained an SNP that caused a premature stop codon in its coding region,resulting in a truncated protein compared to the functional Ali-A1 protein.The Ali-A1 protein contained two ethylene-responsive element binding factor-associated amphiphilic repression(EAR)motifs,one at the N terminus(EAR-N)and the other at the C terminus(EAR-C),and they were involved in interactions with the wheat co-repressor protein TOPLESS(TPL1).The ali-A1 protein retained the EAR-N motif but lost the EAR-C motif,resulting in the attenuated ability to interact with TPL1.The tpl1 mutant produced a longer awn compared to the wild type.Ali-A1 repressed the transcription of two downstream genes,TaLRP-A1 and TaARF-B1,involved in endogenous auxin concentrations and auxin responses in wheat.We concluded that the awn length is regulated not only by the ALI-A1 gene at transcript levels but also by Ali-A1 and TPL1 at the protein level in wheat.
