5gi4
DEAD-box RNA helicaseDEAD-box RNA helicase
Structural highlights
FunctionDEAD_ECOLI DEAD-box RNA helicase involved in various cellular processes at low temperature, including ribosome biogenesis, mRNA degradation and translation initiation. Exhibits RNA-stimulated ATP hydrolysis and RNA unwinding activity at low temperature. Involved in 50S ribosomal subunit assembly, acting after SrmB, and could also play a role in the biogenesis of the 30S ribosomal subunit. In addition, is involved in mRNA decay, via formation of a cold-shock degradosome with RNase E. Also stimulates translation of some mRNAs, probably at the level of initiation.[HAMAP-Rule:MF_00964][1] [2] [3] [4] [5] [6] Publication Abstract from PubMedCsdA has been proposed to be essential for the biogenesis of ribosome and gene regulation after cold shock. However, the structure of CsdA and the function of its long C-terminal regions are still unclear. Here, we solved all of the domain structures of CsdA and found two previously uncharacterized auxiliary domains: a dimerization domain (DD) and an RNA-binding domain (RBD). Small-angle X-ray scattering experiments helped to track the conformational flexibilities of the helicase core domains and C-terminal regions. Biochemical assays revealed that DD is indispensable for stabilizing the CsdA dimeric structure. We also demonstrate for the first time that CsdA functions as a stable dimer at low temperature. The C-terminal regions are critical for RNA binding and efficient enzymatic activities. CsdA_RBD could specifically bind to the regions with a preference for single-stranded G-rich RNA, which may help to bring the helicase core to unwind the adjacent duplex. Insights into the Structure of Dimeric RNA Helicase CsdA and Indispensable Role of Its C-Terminal Regions.,Xu L, Wang L, Peng J, Li F, Wu L, Zhang B, Lv M, Zhang J, Gong Q, Zhang R, Zuo X, Zhang Z, Wu J, Tang Y, Shi Y Structure. 2017 Dec 5;25(12):1795-1808.e5. doi: 10.1016/j.str.2017.09.013. Epub, 2017 Oct 26. PMID:29107486[7] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
|
|