Liu Y, Ishii S, Tokai M, Tsutsumi H, Ohki O, Akada R, Tanaka K, Tsuchiya E, Fukui S, Miyakawa T
Department of Fermentation Technology, Faculty of Engineering, Hiroshima University, Japan.
Mol Gen Genet. 1991 May;227(1):52-9. doi: 10.1007/BF00260706.
Saccharomyces cerevisiae genomic clones that encode calmodulin-binding proteins were isolated by screening a lambda gt11 expression library using 125I-labeled calmodulin as probe. Among the cloned yeast genes, we found two closely related genes (CMP1 and CMP2) that encode proteins homologous to the catalytic subunit of phosphoprotein phosphatase. The presumed CMP1 protein (62,999 Da) and CMP2 protein (68,496 Da) contain a 23 amino acid sequence very similar to those identified as calmodulin-binding sites in many calmodulin-regulated proteins. The yeast genes encode proteins especially homologous to the catalytic subunit of mammalian phosphoprotein phosphatase type 2B (calcineurin). The products of the CMP1 and CMP2 genes were identified by immunoblot analysis of cell extracts as proteins of 62,000 and 64,000 Da, respectively. Gene disruption experiments demonstrated that elimination of either or both of these genes had no effect on cell viability, indicating that these genes are not essential for normal cell growth.
通过使用¹²⁵I标记的钙调蛋白作为探针筛选λgt11表达文库，分离出了编码钙调蛋白结合蛋白的酿酒酵母基因组克隆。在克隆的酵母基因中，我们发现了两个密切相关的基因（CMP1和CMP2），它们编码与磷蛋白磷酸酶催化亚基同源的蛋白质。推测的CMP1蛋白（62,999道尔顿）和CMP2蛋白（68,496道尔顿）含有一个23个氨基酸的序列，与许多钙调蛋白调节蛋白中确定为钙调蛋白结合位点的序列非常相似。酵母基因编码的蛋白质与哺乳动物2B型磷蛋白磷酸酶（钙调神经磷酸酶）的催化亚基特别同源。通过对细胞提取物的免疫印迹分析，将CMP1和CMP2基因的产物分别鉴定为62,000道尔顿和64,000道尔顿的蛋白质。基因破坏实验表明，消除这些基因中的一个或两个对细胞活力没有影响，这表明这些基因对于正常细胞生长不是必需的。
