21kDa肌动蛋白结合蛋白丝切蛋白在各组织中的分布及细胞内定位

Distribution among tissues and intracellular localization of cofilin, a 21kDa actin-binding protein.

作者信息

Yonezawa N, Nishida E, Koyasu S, Maekawa S, Ohta Y, Yahara I, Sakai H

机构信息

Department of Biophysics and Biochemistry, Faculty of Science, University of Tokyo, Japan.

出版信息

Cell Struct Funct. 1987 Oct;12(5):443-52. doi: 10.1247/csf.12.443.

DOI:10.1247/csf.12.443

PMID:3315240

Abstract

Cofilin, a 21kDa actin-binding protein, binds to F-actin in a 1:1 molar ratio of cofilin to actin molecule (Nishida, E., S. Maekawa, and H. Sakai, Biochemistry, 23, 5307-5313, 1984) and is capable of controlling actin polymerization and depolymerization in vitro in a pH-sensitive manner (Yonezawa, N., E. Nishida, and H. Sakai, J. Biol. Chem., 260, 14410-14412, 1985). In this study, immunoblot analysis using monospecific antibodies against cofilin showed that cofilin is ubiquitously distributed in a variety of bovine and rat organs and tissues. Cofilin is also present in various cultured cell lines. Indirect immunofluorescence staining of mouse fibroblastic cells and human epidermoid carcinoma cells indicated that cofilin is distributed nearly uniformly in the cytoplasm and is concentrated in ruffling membranes where F-actin is also concentrated as revealed by staining with rhodamine-phalloin. Stress fiber structures were not strongly stained with the anti-cofilin antibody, although stress fiber staining was sometimes observed near the cell periphery in mouse 3T3 cells. These results suggest that the bulk of cofilin may not be associated with F-actin bundles in vivo.

摘要

丝切蛋白是一种21kDa的肌动蛋白结合蛋白，它以丝切蛋白与肌动蛋白分子1:1的摩尔比与F-肌动蛋白结合（西田英、前川幸司、酒井浩，《生物化学》，23卷，5307 - 5313页，1984年），并且能够在体外以pH敏感的方式控制肌动蛋白的聚合和解聚（米泽直、西田英、酒井浩，《生物化学杂志》，260卷，14410 - 14412页，1985年）。在本研究中，使用针对丝切蛋白的单特异性抗体进行免疫印迹分析表明，丝切蛋白广泛分布于多种牛和大鼠的器官及组织中。丝切蛋白也存在于各种培养的细胞系中。对小鼠成纤维细胞和人表皮样癌细胞进行间接免疫荧光染色表明，丝切蛋白在细胞质中分布几乎均匀，并集中在褶皱膜中，如用罗丹明 - 鬼笔环肽染色所示，F-肌动蛋白也集中在那里。应力纤维结构未被抗丝切蛋白抗体强烈染色，尽管在小鼠3T3细胞的细胞周边有时观察到应力纤维染色。这些结果表明，在体内大部分丝切蛋白可能不与F-肌动蛋白束相关。