核桃JrbHLH转录因子家族鉴定与响应冷胁迫基因表达分析

Identification of JrbHLH transcription factor family in walnut and analysis of gene expression in response to chilling stress

为了探究核桃bHLH转录因子家族在响应冷胁迫过程中的作用,本研究通过转录组数据结合隐马尔可夫模型筛选技术在核桃全基因组挖掘出bHLH转录因子家族成员并进行结构分析,进一步对该家族成员响应冷胁迫的差异表达基因进行冷胁迫不同时间与不同组织中的表转录水平分析。结果表明,核桃bHLH转录因子家族包含72个基因,编码72条蛋白,开放阅读框为393-1839 bp,编码的蛋白长度为130-612个氨基酸,等电点为4.61-9.51,均为亲水性蛋白;各成员均含有典型的碱性区域和螺旋-环-螺旋结构域;与拟南芥同家族聚类分析发现,核桃bHLH家族成员可分布到15个亚群,且同源性较高。结合转录组数据筛选到16个响应冷胁迫的差异表达基因,在冷胁迫不同时间后出现不同程度响应,并且在不同组织中存在特异性表达。本研究将为核桃bHLH转录因子家族在响应冷胁迫过程中的作用研究奠定基础。

In order to explore the role of the walnut bHLH transcription factor family in response to chilling stress,this study used the constructive transcriptome data combined with the Hidden Markov model screening technology to mine the bHLH transcription factor family members in the whole walnut genome and conduct structural analysis.Then the differentially expressed genes of this family in response to chilling stress were analyzed in different tissues at different times of chilling stress.The results showed that the walnut bHLH transcription factor family contained 72 genes,encoding 72 proteins,whose open reading frame were 393-1839 bp.The length of the encoded proteins were 130-612 amino acids with the isoelectric points ranged in 4.61-9.51.Each member contained a typical basic region and helix-loop-helix domain.Cluster analysis with Arabidopsis thaliana showed that the members of the walnut bHLH family can be divided into 15 subgroups with high homology.Combined with transcriptome data,16 differentially expressed genes in response to chilling stress were screened out.They were specifically expressed in different tissues responding differently to chilling stress at different times.This study will lays a foundation for the study of the role of the walnut bHLH transcription factor family in response to chilling stress.