期刊
MOLECULAR CELL
卷 52, 期 5, 页码 643-654出版社
CELL PRESS
DOI: 10.1016/j.molcel.2013.10.005
关键词
-
资金
- Swiss National Science Foundation (SNSF)
- National Center of Excellence in Research (NCCR) Structural Biology program of the SNSF
- European Research Council under the European Community [250071]
- Boehringer-Ingelheim Fonds
- NIH [R01 GM078024]
- Packard and Lucile Award in Science and Engineering
The universally conserved signal recognition particle (SRP) system mediates the targeting of membrane proteins to the translocon in a multistep process controlled by GTP hydrolysis. Here we present the 2.6 angstrom crystal structure of the GTPase domains of the E. coli SRP protein (Ffh) and its receptor (FtsY) in complex with the tetraloop and the distal region of SRP-RNA, trapped in the activated state in presence of GDP:AlF4. The structure reveals the atomic details of FtsY recruitment and, together with biochemical experiments, pinpoints G83 as the key RNA residue that stimulates GTP hydrolysis. Insertion of G83 into the FtsY active site orients a single glutamate residue provided by Ffh (E277), triggering GTP hydrolysis and complex disassembly at the end of the targeting cycle. The complete conservation of the key residues of the SRP-RNA and the SRP protein implies that the suggested chemical mechanism of GTPase activation is applicable across all kingdoms.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据