马铃薯miR319基因家族靶基因预测及其功能分析

Targets Prediction and Function Analysis of Potato miR319 Gene Family

通过生物信息分析发现,马铃薯miR319基因家族(Stu-miR319)共有3个前体基因,可生成5种成熟序列。序列比对发现,miR319成熟体序列在不同物种间具有高度的保守性,保守位点的分布差异较大。通过构建miR319前体基因的系统演化树发现,Stu-miR319的3个前体基因分属不同分支,且不同物种间的演化关系存在差异。组织特异性表达分析结果表明,Stu-miR319的5种成熟体在叶片中均有高表达。通过构建Stu-miR319前体基因过量表达转基因植株以及转录组测序分析发现,Stu-miR319-5p、Stu-miR319-3p、Stu-miR319a-5p和Stu-miR319b各有4个候选靶基因,Stu-miR319a-3p有2个候选靶基因。通过透射电镜分析发现,在Stu-miR319过量表达的植株中,导管细胞的细胞壁均有降解趋势,说明Stu-miR319基因家族对调控导管细胞细胞壁的完整性具有重要作用。

The Stu-miR319 sequences were analyzed to illustrate the function of miR319 gene family in potato.The results showed that there were three Stu-miR319 precursor genes generating five mature sequences.Sequence alignment showed that miR319 mature sequences were highly conserved among different species,while the conservative location distributions are quite different.Phylogenetic analysis revealed that these three Stu-miR319 precursor genes belonged to different clades,which had different evolutionary relationships.Tissue specific expression analysis showed that five mature Stu-miR319 were highly expressed in leaves.Three Stu-miR319 precursor genes overexpressing transgenic lines were generated,and the candidate targets of each Stu-miR319 mature sequences were analyzed.The results showed that each of Stu-miR319-5p,Stu-miR319-3p,Stu-miR319A-5p and Stu-miR319b have four candidate targets,while Stu-miR319a-3p has only two.Transmission electron microscopy analysis showed that the cell wall of leaf vessel elements in lines with Stu-miR319 overexpressing was severely degraded.The results indicate that the Stu-miR319 gene family plays an important role in regulating the cell wall integrity of leaf vessel elements.