毛竹PeCIGRs基因的克隆及表达分析

Cloning and expression analysis of PeCIGRs gene from Phyllostachys edulis

【目的】探究PeCIGRs基因在毛竹Phyllostachysedulis茎秆发育和逆境胁迫中的作用,为毛竹高生长及抗逆机制研究提供参考。【方法】以3 m幼竹中部位置的节间为材料进行PeCIGRs基因的克隆,利用生物信息学分析探究PeCIGRs蛋白的理化性质和系统进化关系,基于转录组数据对PeCIGRs基因在不同组织和非生物胁迫(盐、干旱)、植物生长调节剂(脱落酸、水杨酸)处理下的表达模式进行分析。【结果】在毛竹中共克隆得到4条CIGR基因,依次命名为PeCIGR1-a、PeCIGR1-b、PeCIGR2-a、PeCIGR2-b。4条CIGR基因核苷酸序列长度为1635~1716 bp,氨基酸序列长度为544~571 bp。多序列比对发现:4条CIGR基因均具有保守的GRAS结构域,属于GRAS家族。组织特异性表达分析发现:PeCIGRs基因主要在毛竹茎秆表达,且在3 m高幼竹顶部达到峰值。此外,不同非生物胁迫和植物生长调节剂处理表达分析发现:在干旱(PEG)、盐(NaCl)胁迫和水杨酸(SA)处理下,PeCIGRs基因相对表达量均呈现先升高后下降的趋势。在脱落酸处理下,PeCIGR1-a、PeCIGR1-b基因相对表达量呈现先升高后下降的趋势,PeCIGR2-a、PeCIGR2-b则在处理24 h后呈现下调趋势。【结论】PeCIGRs基因参与调控毛竹茎秆生长发育、非生物胁迫(盐、干旱)响应以及植物生长调节剂(脱落酸、水杨酸)应答。

[Objective]The aim is to explore the role of PeCIGRs in the development of Phyllostachys edulis stem and abiotic stresss,as to provide reference for the study of high growth and stress resistance mechanism.[Method]The PeCIGRs gene was cloned from the internodes located in the middle of a 3-m young Ph.edulis.The physical and chemical properties and phylogenetic relationship of PeCIGRs protein were explored by bioinformatics analysis.The expression pattern of PeCIGRs gene in different tissues and under abiotic stresses and hormone treatment were analyzed based on transcriptome data.[Result]Four CIGR genes were cloned from Ph.edulis,named PeCIGR1-a,PeCIGR1-b,PeCIGR2-a and PeCIGR2-b.The nucleotide sequence length of the four CIGR genes was 1635−1716 bp,and the amino acid sequence length was 544−571 bp.Multiple sequence alignment revealed that all four CIGR genes had conserved GRAS domains,which belonged to GRAS family.Tissue-specific expression analysis revealed that PeCIGRs was mainly expressed in Ph.edulis stem and reached its peak at the top of 3-m young Ph. edulis. In addition, the expression analysis under different stresses and hormone treatments found that PeCIGRs showed a trend of first increasing and then decreasing under drought, salt stress and salicylic acid treatment. Under abscisic acid treatment, PeCIGR1-a and PeCIGR1-b genes increased first and then decreased, while PeCIGR2-a and PeCIGR2-b showed a downward trend after 24 h of treatment. [Conclusion] PeCIGRs gene is involved in the regulation of the growth and development of Ph. edulis stem, and response to abiotic stress (drought and salt) and hormone (abscisic acid and salicylic acid) as well.