酿酒酵母新型分泌缺陷突变株突变基因的鉴定  

Characteristics identification of the mutated gene in a secretion-deficient mutant strain of Saccharomyces cerevisiae with new secretory deficiency performance

作　　者：刘泽静[1] 张媚[1] 薛文达[1] 彭飞[1] 许晓风[1] 

机构地区：[1]南京师范大学生命科学学院,南京210046

出　　处：《安徽农业大学学报》2010年第4期703-708,共6页Journal of Anhui Agricultural University

基　　金：南京师范大学回国人员科研启动基金(2009104XLH0047)资助

摘　　要：对酿酒酵母新型分泌缺陷突变株分泌缺陷特性进行鉴定,结果发现Invertase和Bgl2p的分泌在37℃下受阻,但电镜观察未见胞内分泌小泡积累。用酵母基因组文库挽救突变株,克隆挽救片段上各候选基因与pRS315构建重组质粒并转化突变株以检验它们的挽救效果,发现具有挽救功能的基因是TEL2。从突变株克隆了TEL2的全序列并进行序列测定,检测到了两个突变位点,即:P367→L,S545→F。对该基因突变前后编码的蛋白质产物进行了生物信息学分析,推测出TEL2蛋白可能参与极性外排途径的结构功能域在246～434氨基酸范围内。本试验首次揭示了端粒长度调控基因TEL2在极性外排途径中的重要作用。The secretion characters of a new secretion-deficient mutant of Saccharomyces cerevisiae were identified,and the results showed both Invertase and Bgl2p secretion were blocked at 37℃,while no intracellular vesicle accumulation was observed under electron microscopy.Yeast genomic library was used to transform the mutant to scan the rescue fragment,and a rescue fragment which contained two genes of ESP1 and TEL2 was obtained.ESP1 and TEL2 were cloned separately and ligated to pRS315 to establish the single gene rescue recombinant plasmids and they were transformed into the mutant to test the rescue effect of each candidate gene.As a result,only TEL2 showed the rescue function.The mutated sequence of TEL2 was then cloned from mutant strain and sequenced,and two mutated amino acids were found e.g.P367→L and S545→F.Furthermore,the translation products of TEL2 and mutated TEL2 were analyzed by using bioinformatics tools and their structural/functional domain related to exocytosis was supposed to be within the region of residues 246～434.This is the first time to reveal the relation of TEL2 with polarized exocytosis pathway,though it has long been known as a telomere length maintaining gene.

关 键 词：酿酒酵母 分泌缺陷突变株 TEL2 极性外排途径 

分 类 号：Q75[生物学—分子生物学]