title: A time-resolved investigation of ribosomal subunit association.
abstract: The notion that the ribosome is dynamic has been supported by various biochemical techniques, as well as by differences observed in high-resolution structures of ribosomal complexes frozen in various functional states. Yet, the mechanisms and extent of rRNA dynamics are still largely unknown. We have used a novel, fast chemical-modification technique to provide time-resolved details of 16 S rRNA structural changes that occur as bridges are formed between the ribosomal subunits as they associate. Association of different 16 S rRNA regions was found to be a sequential, multi-step process involving conformational rearrangements within the 30 S subunit. Our results suggest that key regions of 16 S rRNA, necessary for decoding and tRNA A-site binding, are structurally altered in a time-dependent manner by association with the 50 S ribosomal subunits.
authors.affiliation: Division of Biological Sciences, The University of Montana, Missoula, MT 59812, USA.
authors.forename: Scott P
authors.initials: SP
authors.lastname: Hennelly
authors.forename: Ayman
authors.initials: A
authors.lastname: Antoun
authors.forename: Måns
authors.initials: M
authors.lastname: Ehrenberg
authors.forename: Claudio O
authors.initials: CO
authors.lastname: Gualerzi
authors.forename: William
authors.initials: W
authors.lastname: Knight
authors.forename: J Stephen
authors.initials: JS
authors.lastname: Lodmell
authors.forename: Walter E
authors.initials: WE
authors.lastname: Hill
mesh_terms: D020029:Base Pairing; D001665:Binding Sites; D018360:Crystallography, X-Ray; D004926:Escherichia coli / Q000737:chemistry / Q000378:metabolism; D008958:Models, Molecular; D009690:Nucleic Acid Conformation; D011487:Protein Conformation; D012329:RNA, Bacterial / Q000737:chemistry / Q000378:metabolism; D012336:RNA, Ribosomal, 16S / Q000737:chemistry* / Q000378:metabolism; D012343:RNA, Transfer / Q000737:chemistry* / Q000378:metabolism; D012270:Ribosomes / Q000378:metabolism*; D013997:Time Factors
chemical_list: D012329:RNA, Bacterial; D012336:RNA, Ribosomal, 16S; D012343:RNA, Transfer