6q6r
From Proteopedia
Recognition of different base tetrads by RHAU: X-ray crystal structure of G4 recognition motif bound to the 3-end tetrad of a DNA G-quadruplex
Structural highlights
FunctionDHX36_HUMAN Proposed to have a global role in regulating mRNA expression including transcriptional regulation and mRNA stability. Binds with high affinity to and resolves tetramolecular RNA and DNA quadruplex structures. Unwinds intramolecular quadruplexes derived from the ZIC1 and the MYC promoters. Binds to quadruplex structures in the promoters of YY1 and ALPL genes and regulates their expression. Binds to telomerase RNA template component (TERC) 5'-end (nucleotides 1-43) and unwinds an internal quadruplex formation in TERC 5'-end to promote P1 helix formation; the P1 helix acts as a template boundary ensuring accurate reverse transcription and is disrupted by quadruplex formation. May be involved in regulation of telomere length. Plays a role in degradation and deadenylation of mRNAs containing in their 3'-UTR the consensus ARE sequence element. May function in sex development and spermatogenesis. May play a role in ossification.[1] [2] [3] [4] [5] [6] [7] [8] [9] Publication Abstract from PubMedG-quadruplexes (G4) are secondary structures of nucleic acids that can form in cells and have diverse biological functions. Several biologically important proteins interact with G-quadruplexes, of which RHAU - a helicase from the DEAH-box superfamily, was shown to bind and unwind G-quadruplexes efficiently. We report a X-ray co-crystal structure at 1.5 A resolution of an N-terminal fragment of RHAU bound to the exposed tetrad of a parallel-stranded G-quadruplex. The RHAU peptide folds into an L-shaped alpha-helix, and binds to the G-quadruplex through pi-stacking and electrostatic interactions. X-ray crystal structure of our complex identified key amino acid residues important for G-quadruplex-peptide binding interaction at the 3'-end G*G*G*G tetrad. Together with previous solution and crystal structures of RHAU bound to the 5'-end G*G*G*G and G*G*A*T tetrads, our crystal structure highlights the occurrence of a robust G-quadruplex recognition motif within RHAU that can adapt to different accessible tetrads. Recognition of different base tetrads by RHAU: X-ray crystal structure of the G4 recognition motif bound to the 3'-end tetrad of a DNA G-quadruplex.,Heddi B, Vee Cheong V, Schmitt E, Mechulam Y, Tuan Phan A J Struct Biol. 2019 Oct 3. pii: S1047-8477(19)30210-2. doi:, 10.1016/j.jsb.2019.10.001. PMID:31586599[10] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. Loading citation details.. Citations No citations found See AlsoReferences
|
|
Categories: Homo sapiens | Large Structures | Unidentified | Cheong VV | Heddi B | Mechulam Y | Phan AT | Schmitt E