粟酒裂殖酵母Cyc2定位及功能的研究  

Localization and Function of Cyc2 in Schizosaccharomyces pombe

作　　者：杨贵红 黄鹰[1] Yang Guihong;Huang Ying(School of Life Sciences,Nanjing Normal University,Nanjing 210023,China)

机构地区：[1]南京师范大学生命科学学院,江苏南京210023

出　　处：《南京师大学报（自然科学版）》2020年第2期108-113,139,共7页Journal of Nanjing Normal University(Natural Science Edition)

基　　金：国家自然科学基金项目(31770810、31470778).

摘　　要：芽殖酵母中CYC2蛋白与Cyt c的装配有关,对线粒体功能的发挥十分重要.但该蛋白在粟酒裂殖酵母中的同源蛋白Cyc2的功能还未可知,本文研究了粟酒裂殖酵母中Cyc2的定位及其对线粒体功能的影响.构建Δcyc2菌株后观察其在甘油培养基上的表型,并构建回补菌株验证表型,结果发现Δcyc2在甘油板上表现出了生长缺陷;通过检测Δcyc2菌株内由mtDNA编码的呼吸链蛋白的表达量,结果发现Cyc2的缺失并不会影响呼吸链蛋白的表达;利用生物信息学分析Cyc2序列,发现它的N端含有一段线粒体定位序列(MTS)且该蛋白没有跨膜区域,为确定该蛋白在细胞中的具体定位,分别构建Cyc-GFP和Tom20-Flag/Cyc2-Myc菌株,通过荧光观察及生化方法确定该蛋白为线粒体内膜外周蛋白.综上所述,粟酒裂殖酵母Cyc2为线粒体内膜外周蛋白,不会影响线粒体呼吸链蛋白的表达,可能通过其他途径参与线粒体功能的发挥.The CYC2 protein in budding yeast is related to the assembly of Cyt c,which is of great significance to the function of mitochondria. But in Schizosaccharomyces pombe,the function of the protein Cyc2 which is the homologous protein of CYC2 has not been known. In this paper,the location and function of Cyc2 were studied. The homologous recombination method was used to construct Δcyc2 mutants,it was observed the phenotype of Δcyc2 strain on non-fermentation medium(glycerol plate),and construct a complementing strain to verify the phenotype. As a result,Δcyc2 showed growth defects on the glycerol plate. By detecting the expression of respiratory streptavidin encoded by the mitochondrial genome,it was found that the deletion of cyc2 does not affect the expression of respiratory streptavidin. The sequence of Cyc2 was analyzed by bioinformatics and the result showed that the N-terminus of Cyc2 contained a mitochondrial localization sequence(MTS)and the protein has no transmembrane region. In order to determine the specific localization of the protein in the cell,it was constructed Cyc-GFP and Tom20-Flag/Cyc2-Myc strains,respectively,and identified the protein as a mitochondrial inner membrane peripheral protein by fluorescence observation and biochemical methods. To sum up,Cyc2 is a mitochondrial inner membrane peripheral protein,which does not affect the expression of mitochondrial respiratory chain protein,and may affect the function of mitochondria through other channels.

关 键 词：粟酒裂殖酵母 线粒体 Cyc2 定位 

分 类 号：R331.31[医药卫生—人体生理学]