DEAD-box-protein-assisted RNA structure conversion towards and against thermodynamic equilibrium values

JOURNAL OF MOLECULAR BIOLOGY

卷:368

Article

Yang, Quansheng ; Fairman, Margaret E. ; Jankowsky, Eckhard

关键词: DEAD-box;    helicase;    RNA structure;    ATPase;    RNA chaperone;   

DOI  :  10.1016/j.jmb.2007.02.071

来源: Elsevier

【 摘 要 】

RNAs in biological processes often interconvert between defined structures. These RNA structure conversions are assisted by proteins and are frequently coupled to ATP hydrolysis. It is not well understood how OH proteins coordinate RNA structure conversions and which role ATP hydrolysis has in these processes. Here, we have investigated in vitro how DEAD-box ATPase Ded1 facilitates RNA structure conversions in a simple via two distinct pathways. One pathway requires ATP hydrolysis and involves the complete disassembly of the RNA strands. This pathway represents a kinetically controlled steady state between the RNA structures, which allows formation of less stable from more stable RNA conformations and thus RNA structure conversion against thermodynamic equilibrium values. The other pathway is ATP-independent and proceeds via multipartite intermediates that are stabilized by Ded1. Our results provide a basic mechanistic framework for protein-assisted RNA structure conversions that illuminates the role of ATP hydrolysis and reveal an unexpected diversity of pathways. (c) 2007 Elsevier Ltd. All rights reserved.

【 授权许可】

Free