How differential distributions of actin-bindingproteins are formed in living cells.

肌动蛋白结合蛋白的差异分布如何在活细胞中形成。

基本信息

批准号：
15570153
负责人：
ISHIKAWA Ryoki
金额：
$ 2.18万
依托单位：
Gunma University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2003
资助国家：
日本
起止时间：
2003 至 2004
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-15570153/
关键词：
actin tropomyosin actin-binding protein fascin drebrin

项目摘要

We examined the distribution and dynamics of actin-binding proteins in Ng108-15 cells. EGFP/fascin localized in filopodia. Pseudo-unphosphorylated mutant, in which 39-serine of fascin was replaced to asparatic acid, localized in filopodia while pseudo-phosphorylated mutant, in which 39-serine was replaced to alanine, showed dispersed distribution, suggesting that localization of fascin is regulated by phosphorylation. EGFP/smooth muscle type tropomyosin localized only in stress fibers, while EGFP/nonmusle type tropomyosin localized in stress fibers, filopodia, and lamellipodia. EGFP/caldesmon localized in all the actin structures.Reconstituted characterization of purified proteins revealed that fascin formed tight F-actin bundles with polarity. Drebrin bound to F-actin with a stoichiometry of 5 actin versus 1 drebrin molecule. Drebrin inhibited the actin-binding of caldesmon, actin-binding of tropomyosin, and actin-binding of fascin.These results suggest that competitive binding between drebrin and tropomyosin/caldesmon, between drebrin and fascin, and between fascin and tropomyosin/caldesmon may cause the differential localization fascin, drebrin, and tropomyosin/caldesmon, resulting in different organization of actin structure.

我们检查了NG108-15细胞中肌动蛋白结合蛋白的分布和动力学。 EGFP/FASTIN位于丝状地位。伪非磷酸化的突变体，其中39个fascin的serine被替换为可叠酸的酸，而伪磷酸化的突变体，而伪磷酸化的突变体，其中39个链氨酸被替换为丙氨酸，显示出分散的分布，表明Fascin的定位受磷酸化的调节。 EGFP/平滑肌类型的肌球蛋白仅位于应力纤维中，而EGFP/Nonmusle型tropomyosin局部定位于应力纤维，丝状纤维和薄片中。 EGFP/caldesmon局部位于所有肌动蛋白结构中。纯化蛋白质的均取决于表征，表明Fascin形成了具有极性的紧密F-肌动蛋白束。 Drebrin与F-肌动蛋白结合，其化学计量法为5肌动蛋白与1个DREBRIN分子。 Drebrin inhibited the actin-binding of caldesmon, actin-binding of tropomyosin, and actin-binding of fascin.These results suggest that competitive binding between drebrin and tropomyosin/caldesmon, between drebrin and fascin, and between fascin and tropomyosin/caldesmon may cause the differential localization fascin, drebrin, and tropomyosin/caldesmon,导致肌动蛋白结构的不同组织。