小麦TCP基因家族的全基因组鉴定和对热胁迫的响应

Genome-Wide Identification of the Wheat TCP Gene Family and Its Response to Heat Stress

TCP是植物发育调控的重要转录因子。为了挖掘小麦TCP基因的功能,本研究利用生物信息学方法和qRT-PCR技术,对小麦TCP基因家族进行全基因组鉴定和在热胁迫下的表达分析。全基因组鉴定结果表明,普通小麦品种中国春中存在58个非冗余的TaTCP基因。根据与AtTCPs和OsTCPs的系统发育分析,在小麦中分别有26个PCF、20个CIN和12个CYC/TB1聚类。进一步预测TaTCP基因在达尔文进化下的压力选择,发现除了TaTCP16-A相对于乌拉尔图小麦中直系同源基因是正向选择,其他基因都是纯化选择的过程。利用在线RNA-seq数据分析TaTCPs基因在5种组织器官中与冷、热和干旱胁迫下的表达图谱,结果显示,小麦TCP基因在不同的组织和胁迫中存在差异表达。最后,通过qRT-PCR技术检测12个不同发育阶段的小麦叶片在短期热胁迫下TaTCP5部分同源基因的表达水平,结果表明,在35℃下处理1h,TaTCP5-D的相对表达量在拔节期、拔节后期、孕穗前期和抽穗期都有明显的上调,这些结果为进一步研究TaTCP基因的功能奠定了良好的基础。

TCP is an important transcription factor regulating plant development.In order to explore the function of wheat TCP genes,the TCP family of wheat genome was identified through genome and bioinformatics analysis and its expression responding to heat stress was detected by qRT-PCR.The results showed that there are 58 non-redundant TaTCPs genes in wheat cultivar‘Chinese Spring’.According to the phylogenetic analysis with AtTCPs and OsTCPs,there are 26 PCF,20 CIN and 12 CYC/TB1 clusters in wheat.The pressure selection of TaTCPs genes under Darwinian evolution was further predicted.It was found that,except for the positive selection of TaTCP16-A relative to T.urartu orthologous gene,other genes were purification selection.Online RNA-seq data was used to analyze expression profiles of TaTCPs genes under cold,heat,and drought stress in five tissues and organs.The results showed that there were differences among the expression of TCP gene in different tissues of wheat and under various stresses.Finally,the expression of three TaTCP5 alleles in wheat leaves at 12 different developmental stages under short-term heat stress were detected by qRT-PCR analysis.The expression changes of the three TaTCP5 alleles showed that the relative expression of TaTCP5-D was significantly increased at jointing stage,late jointing stage,early booting stage and heading stage at 35℃for 1 h.These results laid a good foundation for further study of wheat TCP gene function.