Suppr超能文献

酵母核孔蛋白Nup145p前体的自催化切割

Self-catalyzed cleavage of the yeast nucleoporin Nup145p precursor.

作者信息

Teixeira M T, Fabre E, Dujon B

机构信息

Unité de Génétique Moléculaire des levures, Institut Pasteur, Département des Biotechnologies, 25 Rue du Docteur Roux, 75724 Paris Cedex 15, France.

出版信息

J Biol Chem. 1999 Nov 5;274(45):32439-44. doi: 10.1074/jbc.274.45.32439.

Abstract

Nup145p is a component of the nuclear pore complex of Saccharomyces cerevisiae and is essential for mRNA export. Nup145p and its apparent vertebrate homologue are the only known nucleoporins to be composed of two functionally independent peptide moieties resulting from the post-translational cleavage of a large precursor molecule. In this study, the proteolytic cleavage site of Nup145p has been mapped upstream of an evolutionary conserved serine residue. Cleavage occurs at the same site when a precursor is artificially expressed in Escherichia coli. A hydroxyl-containing residue is critical for the reaction, although a thiol-containing residue offers an acceptable replacement. In vitro kinetics experiments using a purified precursor molecule demonstrate that the cleavage is self-catalyzed and that the catalytic domain lies within the N-terminal moiety. Taken altogether, our data are consistent with a proteolytic mechanism involving an N>O acyl rearrangement and a subsequent ester intermediate uncovered in other self-processing proteins.

摘要

Nup145p是酿酒酵母核孔复合体的一个组成部分,对mRNA输出至关重要。Nup145p及其明显的脊椎动物同源物是已知仅有的由一个大的前体分子经翻译后切割产生的两个功能独立的肽部分组成的核孔蛋白。在本研究中,Nup145p的蛋白水解切割位点已定位在一个进化保守的丝氨酸残基上游。当在大肠杆菌中人工表达前体时,切割发生在同一位点。尽管含硫醇的残基可提供可接受的替代,但含羟基的残基对该反应至关重要。使用纯化的前体分子进行的体外动力学实验表明,切割是自我催化的,并且催化结构域位于N端部分。总体而言,我们的数据与涉及N>O酰基重排和随后在其他自我加工蛋白中发现的酯中间体的蛋白水解机制一致。

文献AI研究员

20分钟写一篇综述,助力文献阅读效率提升50倍。

立即体验

用中文搜PubMed

大模型驱动的PubMed中文搜索引擎

马上搜索

文档翻译

学术文献翻译模型,支持多种主流文档格式。

立即体验