小麦E3泛素连接酶基因TaSINA-3A与多种环境下的株高和千粒重相关

An E3 ubiquitin ligase gene TaSINA-3A is associated with plant height and 1000-grain weight in various environments in wheat

E3泛素连接酶SINA(seven in absentia)家族参与植物的生长发育、免疫共生并响应逆境胁迫。本研究克隆了位于小麦染色体3A上的TaSINA-3A基因,其基因组序列长度为3897 bp,其中启动子区为2001 bp,基因序列为1896 bp,编码244个氨基酸,在50~91位氨基酸处有一个RING(really interesting new gene)保守结构域。RT-qPCR结果显示,TaSINA-3A基因在小麦的各个发育阶段的不同组织中均有表达。序列多态性分析表明,在TaSINA-3A的启动子区存在33个SNP(single nucleotide polymorphism)位点,编码区有4个SNP位点。基于启动子区的变异位点SNP-159、SNP-418和SNP-1286开发分子标记,扫描小麦自然群体,并与表型性状进行关联分析。结果表明,标记CAPS-159与多种环境下的株高和倒二节长显著相关,SNP-159-C是倒二节较短的矮秆等位变异,标记dCAPS-418分别与多种环境下的穗长和千粒重显著关联,SNP-418-A是长穗、高千粒重的优异等位变异;TaSINA-3A负调控穗和籽粒的发育,TaSINA-3A的表达可能受到MYC转录因子的抑制;在我国小麦育种进程中SNP-418-A受到正向选择,在育成品种中的频率逐步增加,但尚未充分利用。研究结果为深入探讨小麦株高、倒二节长及产量的形成机制提供参考,并为培育高产稳产广适新品种提供了基因资源。

The SINA(seven in absentia)family of E3 ubiquitin ligases is involved in plant growth and development,immune symbiosis and response to stresses.In this study,we cloned the TaSINA-3A gene located on chromosome 3A in wheat.The TaSINA-3A genome sequence spans 3897 bp,including a 2001 bp promoter region and a 1896 bp coding region.The TaSINA-3A genome encods 244 amino acids,and contains a conserved RING(really interesting new gene)domain at amino acids 50-91.Sequence polymorphism analysis revealed the presence of 33 single nucleotide polymorphisms(SNPs)in the promoter region and 4 SNPs in the coding region.Quantitative analysis showed that the TaSINA-3A gene exhibited tissue-specific expression during different developmental stages of wheat.Molecular markers based on the SNP loci SNP-159,SNP-418,and SNP-1286 in the promoter region were developed to genotype the natural population of wheat.Association analysis between genotypes and phenotypic traits revealed significant associations between molecular marker CAPS-159 and penultimate internode length(PIL)and plant height(PH)under various environmental conditions,and Association analysis between genotypes and phenotypic traits revealed significant associations between molecular marker dCAPS-418 and spike length(SL)and 1000-grain weight(TGW)under various environmental conditions.Among these associations,the allelic variant SNP-159-C was associated with shorter PIL and PH,while SNP-418-A was associated with longer SL and higher TGW.TaSINA-3A was found to negatively regulate spike and grain development,and its expression may be suppressed by the MYC transcription factor.In the context of wheat breeding in China,SNP-418-A has been positively selected and its frequency in modern cultivars has gradually increased;however,its full potential has not been fully utilized.These results provide valuable insights for further exploration of the mechanisms underlying penultimate internode length,plant height,spike length,and grain yield.Moreover,they provide genetic resources for breeding new varieties with high yield,stable yield and wide suitability.