Rarely at rest

Abstract

RNA helicases are compact, machine-like proteins that can harness the energy of nucleoside triphosphate binding and hydrolysis to dynamically remodel RNA structures and protein-RNA complexes. Through such activities, helicases participate in virtually every process associated with the expression of genetic information. Often found as components of multi-enzyme assemblies, RNA helicases facilitate the processivity of RNA degradation, the remodeling of protein interactions during maturation of structured RNA precursors, and fidelity checks of RNA quality. In turn, the assemblies modulate and guide the activities of the helicases. We describe the roles of RNA helicases with a conserved “DExD/H box” sequence motif in representative examples of such machineries from bacteria, archaea and eukaryotes. The recurrent occurrence of such helicases in complex assemblies throughout the course of evolution suggests a common requirement for their activities to meet cellular demands for the dynamic control of RNA metabolism.

Keywords: :

• DExD/H box helicase
• RNA degradosome
• RNA helicase
• RNA surveillance
• RNA turnover
• RNA-protein interactions
• exosome
• non-coding RNA
• post-transcriptional regulation
• ribonuclease

Disclosure of Potential Conflicts of Interest

No potential conflicts of interest were disclosed.

Acknowledgments

The authors are supported by the Wellcome Trust. We thank Martyn Symmons, Gadi Schuster, A.J. Carpousis, Mark Carrington and Patrick Linder for invaluable comments and stimulating discussions. We thank the anonymous reviewers for helpful comments. Resources: the RNA helicase database (www.rnahelicase.org/index.html).