番茄多胺氧化酶(PAO)基因家族鉴定及表达分析

摘要

该研究通过生物信息学手段,从番茄基因组中鉴定出11个编码多胺氧化酶(polyamine oxidase,PAO)的家族基因(命名为SlPAO1～11),分为3个亚家族(Ⅰ、Ⅱ、Ⅲ);基因结构分析、蛋白质二级结构预测、亚细胞定位预测结果均显示,SlPAOs基因家族具有明显的亚家族分类特征.序列和进化分析结果显示,亚家族Ⅰ和Ⅱ中的SlPAO1～8属于典型的PAO基因,而亚家族Ⅲ中的Sl PAO9～11编码蛋白还含有特异性的SWIRM结构域,SlPAO9～11属于组蛋白赖氨酸特异性脱甲基化酶,而非真正的PAO.选取上述鉴定的8个典型SlPAO基因(SlPAO1 8),采用qRT PCR技术对SlPAO1 8基因在不同组织中(干燥种子,新鲜的真叶、子叶、茎、根)的相对表达分析显示,SlPAO1-8在不同组织中的表达水平差异显著,推测SlPAOs基因家族的组织表达多样性与功能多样性之间可能具有一定的相关性.%In this study,we used bioinformatics approaches to retrieve 11 family genes encoding for PAO from tomato genome,which were further named as SlPAO1-11 grouped into three subfamilies (Ⅰ,Ⅱ,and Ⅲ).In addition,gene structure analysis,protein secondary structure prediction and subcellular location prediction results are demonstrated that SlPAOs gene family have distinct subfamily categorization characteristics.Sequence and phylogenetic analysis suggest that SlPAO1-8 belonging to subfamily Ⅱ and Ⅱ are typical PAO genes.Proteins encoded by SlPAO9-11 belonging to subfamily Ⅲ contain specific SWIRM domain,SlPAO9-11 are characterized as histone lysine-specific demethylases,but not real PAO.Then,we used qRT-PCR to analyze the relative expression level of 8 typical SlPAOs (SlPAO1-8) in different tissues (dry seeds,fresh leaf,cotyledon,stem,root) of tomato plant,the results showed that the expression levels of SlPAO1-8 in different tissues were significantly different.It is speculated that there may be a certain correlation between the diversity of expression and functional diversity of the SlPAOs gene family.