4zlc | pdb_00004zlc
Crystal structure of the ROQ domain of human Roquin-2
Structural highlights
Function[RC3H2_HUMAN] Post-transcriptional repressor of mRNAs containing a conserved stem loop motif, called constitutive decay element (CDE), which is often located in the 3'-UTR, as in HMGXB3, ICOS, IER3, NFKBID, NFKBIZ, PPP1R10, TNF and in many more mRNAs (By similarity). Binds to CDE and promotes mRNA deadenylation and degradation. This process does not involve miRNAs (By similarity). In follicular helper T (Tfh) cells, represses of ICOS and TNFRSF4 expression, thus preventing spontaneous Tfh cell differentiation, germinal center B-cell differentiation in the absence of immunization and autoimmunity (By similarity). In resting or LPS-stimulated macrophages, controls inflammation by suppressing TNF expression (By similarity). Also recognizes CDE in its own mRNA and in that of paralogous RC3H2, possibly leading to feedback loop regulation (By similarity). Publication Abstract from PubMedRoquin mediates mRNA degradation by recognizing the constitutive-decay element (CDE) in the 3' untranslated region of the target gene followed by recruitment of the deadenylation machinery. Deficiency or dysfunction of Roquin has been associated with autoimmunity and inflammation. To establish the structural basis for the recognition of CDE RNA by Roquin, the crystal structure of the ROQ domain of human Roquin-2 was determined in ligand-free and CDE-derived RNA-bound forms. The ROQ domain of Roquin-2 folded into a winged-helix structure in which the wing region showed structural flexibility and acted as a lid for RNA binding. The CDE RNA, forming a stem-loop structure, bound to the positively charged surface of the ROQ domain and was mainly recognized via direct interactions with the phosphate backbone in the 5' half of the stem-loop and its triloop and via indirect water-mediated interactions. Structural comparison with Roquin-1 revealed conserved features of the RNA-binding mode. Therefore, it is suggested that the Roquin proteins function redundantly in mRNA degradation. Structure of human Roquin-2 and its complex with constitutive-decay element RNA.,Sakurai S, Ohto U, Shimizu T Acta Crystallogr F Struct Biol Commun. 2015 Aug 1;71(Pt 8):1048-54. doi:, 10.1107/S2053230X15011887. Epub 2015 Jul 29. PMID:26249698[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
| ||||||||||||||||||
