7mpi
From Proteopedia
Stm1 bound vacant 80S structure isolated from cbf5-D95A
Structural highlights
FunctionRSSA1_YEAST Required for the assembly and/or stability of the 40S ribosomal subunit. Required for the processing of the 20S rRNA-precursor to mature 18S rRNA in a late step of the maturation of 40S ribosomal subunits.[1] [2] Publication Abstract from PubMedPseudouridine, the most abundant form of RNA modification, is known to play important roles in ribosome function. Mutations in human DKC1, the pseudouridine synthase responsible for catalyzing the ribosome RNA modification, cause translation deficiencies and are associated with a complex cancer predisposition. The structural basis for how pseudouridine impacts ribosome function remains uncharacterized. Here, we characterized structures and conformations of a fully modified and a pseudouridine-free ribosome from Saccharomyces cerevisiae in the absence of ligands or when bound with translocation inhibitor cycloheximide by electron cryomicroscopy. In the modified ribosome, the rearranged N1 atom of pseudouridine is observed to stabilize key functional motifs by establishing predominately water-mediated close contacts with the phosphate backbone. The pseudouridine-free ribosome, however, is devoid of such interactions and displays conformations reflective of abnormal inter-subunit movements. The erroneous motions of the pseudouridine-free ribosome may explain its observed deficiencies in translation. CryoEM structures of pseudouridine-free ribosome suggest impacts of chemical modifications on ribosome conformations.,Zhao Y, Rai J, Yu H, Li H Structure. 2022 Jul 7;30(7):983-992.e5. doi: 10.1016/j.str.2022.04.002. Epub 2022 , Apr 29. PMID:35489333[3] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
|