THE AMINO TERMINUS OF THE YEAST F1-ATPASE BETA-SUBUNIT PRECURSOR FUNCTIONS AS A MITOCHONDRIAL IMPORT SIGNAL
THE AMINO TERMINUS OF THE YEAST F1-ATPASE BETA-SUBUNIT PRECURSOR FUNCTIONS AS A MITOCHONDRIAL IMPORT SIGNAL
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DOI：
10.1083/jcb.102.2.523
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发表时间：
1986-02-01
影响因子：
7.8
通讯作者：
DOUGLAS, MG
中科院分区：
文献类型：
--
作者：
EMR, SD;VASSAROTTI, A;DOUGLAS, MG
酿酒酵母ATP2基因编码线粒体F1-ATPase的β-亚基蛋白。为了确定该蛋白在体内靶向和输入线粒体所需的氨基酸序列决定因素，我们构建了ATP2基因与大肠杆菌LacZ基因或酿酒酵母SUC2基因(编码转化酶)之间的基因融合。ATP2-LacZ和ATP2-SUC2基因融合编码了在体内有效靶向酵母线粒体的杂交蛋白。线粒体相关的杂交蛋白与线粒体内膜分离，在分离的细胞器中对蛋白酶消化具有抵抗力。通过基因融合和靶向缺陷的ATP2缺失突变体获得的结果提供了证据，证明β-亚基蛋白前体的氨基末端27个氨基酸足以指导该蛋白对酵母线粒体的特异性分选和其输入到细胞器中。此外，我们还观察到某些线粒体相关的Atp2-LacZ和Atp2-SUC2杂合蛋白赋予酵母细胞一种新的呼吸缺陷表型。
The ATP2 gene of Saccharomyces cerevisiae codes for the cytoplasmically synthesized .beta.-subunit protein of the mitochondrial F1-ATPase. To define the amino acid sequence determinants necessary for the in vivo targeting and import of this protein into mitochondria, we have constructed gene fusions between the ATP2 gene and either the Escherichia coli lacZ gene or the S. cerevisiae SUC2 gene (which codes for invertase). The ATP2-lacZ and ATP2-SUC2 gene fusions codes for hybrid proteins that are efficiently targeted to yeast mitochondria in vivo. The mitochondrially associated hybrid proteins fractionate with the inner mitochondrial membrane and are resistant to proteinase digestion in the isolated organelle. Results obtained with the gene fusions and with targeting-defective ATP2 deletion mutants provide evidence that the amino-terminal 27 amino acids of the .beta.-subunit protein precursor are sufficient to direct both specific sorting of this protein to yeast mitochondria and its import into the organelle. Also, we have observed that certain of the mitochondrially associated Atp2-LacZ and Atp2-Suc2 hybrid proteins confer a novel respiration-defective phenotype to yeast cells.