核桃JrMYB44基因的结构与表达分析

Structure and expression analysis of the JrMYB44 gene in Juglans regia

MYB转录因子广泛参与植物生长发育、次生代谢以及植物响应胁迫的调控过程。为研究MYB在核桃生长发育过程中的作用,采用生物信息学方法研究了JrMYB44基因及其编码蛋白的结构特点,并分析了JrMYB44在不同核桃组织和低温胁迫下的转录水平。结果表明,JrMYB44基因长1362 bp,最大开放阅读框966 bp,具1个外显子,无内含子,编码321个氨基酸等电点为7.60,属于弱碱性蛋白,编码蛋白的分子量为34.79 kD,该蛋白无信号肽,且不存在跨膜区域;进一步对JrMYB44编码的蛋白功能预测,其参与依赖ABA途径的非生物胁迫,并且互作蛋白中部分与响应低温胁迫有关,经同源进化分析发现其与毛果杨PtMYB44进化关系较近。低温处理48 h后,“辽宁8号”和“清香”JrMYB44转录表达显著升高,分别是对照组的4.00倍和3.03倍;结合“清香”不同组织转录组数据分析,JrMYB44在“清香”芽、幼叶和雌花中表达量较高,推测其可能参与幼嫩器官发育及响应低温胁迫的调控过程。

The MYB transcription factor was widely involved the in regulation process of plant growth,development,secondary metabolism and response to stress.In order to study the effect of MYB in the growth and development of the Juglans regia,we used bioinformatics method to study the structural characteristics of the JrMYB44 gene and its encoded protein,and analyzed the transcription level of the JrMYB44 under different tissues and low temperature stress.The results showed that the length of the JrMYB44 gene was 1362 bp,the maximum open reading frame was 966 bp.It had one exon,no intron,and the isoelectric point of coding 321 amino acids was 7.60.It was a weak-basic protein,and the molecular weight of the coding protein was 34.79 kD,the protein had no signal peptide and no transmembrane region.Furthermore,the function of the JrMYB44 protein was predicted to be involved in abiotic stress dependent on ABA pathway,its participation depended on the ABA pathway and participated in obiotic stress,and some of the interacting proteins were related to response to low temperature stress.Homologous evolutionary analysis showed that the JrMYB44 was closely related to the evolution of the PtMYB44.After 48 hours of low temperature treatment,the transcriptional expression of the JrMYB44 in‘Liaoning 8’and‘Qingxiang’was significantly increased,which was 4.00 and 3.03 times more than that of the control group,respectively.Combined with the analysis of transcriptome data of different tissues of‘Qingxiang’,the expression of the JrMYB44 was higher in buds,young leaves and female flowers of‘Qingxiang’,suggesting that the JrMYB44 may be involved in the regulation process of young organs development and response to stress.The study laid a foundation for further analysis of the regulatory mechanism of the Juglans regia JrMYB44 gene in response to low temperature stress.