4frg

Crystal structure of the cobalamin riboswitch aptamer domainCrystal structure of the cobalamin riboswitch aptamer domain

Structural highlights 4frg is a 2 chain structure with sequence from Marine metagenome. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Ligands: , , Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Publication Abstract from PubMed Structures of riboswitch receptor domains bound to their effector have shown how messenger RNAs recognize diverse small molecules, but mechanistic details linking the structures to the regulation of gene expression remain elusive. To address this, here we solve crystal structures of two different classes of cobalamin (vitamin B(12))-binding riboswitches that include the structural switch of the downstream regulatory domain. These classes share a common cobalamin-binding core, but use distinct peripheral extensions to recognize different B(12) derivatives. In each case, recognition is accomplished through shape complementarity between the RNA and cobalamin, with relatively few hydrogen bonding interactions that typically govern RNA-small molecule recognition. We show that a composite cobalamin-RNA scaffold stabilizes an unusual long-range intramolecular kissing-loop interaction that controls mRNA expression. This is the first, to our knowledge, riboswitch crystal structure detailing how the receptor and regulatory domains communicate in a ligand-dependent fashion to regulate mRNA expression. B12 cofactors directly stabilize an mRNA regulatory switch.,Johnson JE Jr, Reyes FE, Polaski JT, Batey RT Nature. 2012 Dec 6;492(7427):133-7. doi: 10.1038/nature11607. Epub 2012 Oct 14. PMID:23064232 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See Also Riboswitch 3D structures

spinqualitylabelsall models 4frg, resolution 2.95Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image