辣椒胞质雄性不育系线粒体基因CaATP9的克隆与表达

Clone and Expression Profile Analyses of the Gene CaATP9 in Pepper(Capsicum annuum L.) Male Sterility Line

通过克隆辣椒胞质雄性不育系线粒体基因CaATP9及其表达情况,为研究辣椒胞质雄性不育机理提供依据。以辣椒胞质雄性不育系9704A和同型保持系9704B为试验材料,研究CaATP9的一级结构在2个材料之间的差异和RNA编辑现象,并利用实时荧光定量PCR研究了该基因的时空表达。结果表明,CaATP9的一级结构在2个材料之间没有差异;CaATP9在转录过程中存在5个C→T的编辑位点,导致4个亲水性氨基酸(DNA模板)变换成4个疏水氨基酸,增强了蛋白质的稳定性;CaATP9在辣椒的不同组织中均有表达,但表达量存在一定差异,繁殖器官中的表达量要普遍高于营养器官;在花蕾发育过程中,胞质雄性不育系中CaATP9的表达量与同型保持系存在差异,推测这种表达差异导致胞质雄性不育系花蕾能量供应紊乱,影响小孢子的正常发育而表现不育。

In this research,the pepper cytoplasmic male sterile line 9704 A and the homologous maintainer line 9704 B were used as experimental materials to study the differences between the primary structure of gene CaATP9 and the editing of RNA,and the realtime quantitative PCR was used to study the spatiotemporal expression of gene CaATP9.The results showed that the primary structure of gene CaATP9 did not differ between the two materials;the gene CaATP9 has five C→T editing sites during transcription,resulting in the conversion of four hydrophilic amino acids(DNA template)into four hydrophobic amino acids and enhancing the stability of the protein;gene CaATP9 is expressed in different tissues of pepper,but the expression level in reproductive tissues is generally higher than that in vegetative tissues;the expression level of gene CaATP9 in the male sterile line differed from that of the homologous maintainer line in the development of flower buds.It is speculated that this difference in expression leads to the disorder of the energy supply of the buds of the cytoplasmic male sterile line,affecting the normal development of microspores and showing infertility.