输入蛋白β在微管组装中将Ran与下游靶点偶联中的作用。

Role of importin-beta in coupling Ran to downstream targets in microtubule assembly.

作者信息

Wiese C, Wilde A, Moore M S, Adam S A, Merdes A, Zheng Y

机构信息

Department of Embryology, Howard Hughes Medical Institute, Carnegie Institution of Washington, Baltimore, MD 21210, USA.

出版信息

Science. 2001 Jan 26;291(5504):653-6. doi: 10.1126/science.1057661.

DOI:10.1126/science.1057661

PMID:11229403

Abstract

The guanosine triphosphatase Ran stimulates assembly of microtubule asters and spindles in mitotic Xenopus egg extracts. A carboxyl-terminal region of the nuclear-mitotic apparatus protein (NuMA), a nuclear protein required for organizing mitotic spindle poles, mimics Ran's ability to induce asters. This NuMA fragment also specifically interacted with the nuclear transport factor, importin-beta. We show that importin-beta is an inhibitor of microtubule aster assembly in Xenopus egg extracts and that Ran regulates the interaction between importin-beta and NuMA. Importin-beta therefore links NuMA to regulation by Ran. This suggests that similar mechanisms regulate nuclear import during interphase and spindle assembly during mitosis.

摘要

鸟苷三磷酸酶Ran可刺激非洲爪蟾卵有丝分裂提取物中微管星状体和纺锤体的组装。核有丝分裂器蛋白（NuMA）是一种组织有丝分裂纺锤体极所必需的核蛋白，其羧基末端区域可模拟Ran诱导星状体的能力。该NuMA片段还与核转运因子输入蛋白β特异性相互作用。我们发现，输入蛋白β是非洲爪蟾卵提取物中微管星状体组装的抑制剂，且Ran可调节输入蛋白β与NuMA之间的相互作用。因此，输入蛋白β将NuMA与Ran的调节联系起来。这表明，在间期调节核输入和在有丝分裂期间调节纺锤体组装的机制可能相似。