title: Use of photoaffinity crosslinking and molecular modeling to analyze the global architecture of ribonuclease P RNA.
abstract: Bacterial ribonuclease P (RNase P), an endonuclease involved in tRNA maturation, is a ribonucleoprotein containing a catalytic RNA. The secondary structure of this ribozyme is well established, but comparatively little is understood about its 3-D structure. In this analysis, orientation and distance constraints between elements within the Escherichia coli RNase P RNA-pre-tRNA complex were determined by intra- and intermolecular crosslinking experiments. A molecular mechanics-based RNA structure refinement protocol was used to incorporate the distance constraints indicated by crosslinking, along with the known secondary structure of RNase P RNA and the tertiary structure of tRNA, into molecular models. Seven different structures that satisfy the constraints equally well were generated and compared by superposition to estimate helix positions and orientations. Manual refinement within the range of conformations indicated by the molecular mechanics analysis was used to derive a model of RNase P RNA with bound substrate pre-tRNA that is consistent with the crosslinking results and the available phylogenetic comparisons.
authors.affiliation: Department of Biology, Indiana University, Bloomington 47405.
authors.forename: M E
authors.initials: ME
authors.lastname: Harris
authors.forename: J M
authors.initials: JM
authors.lastname: Nolan
authors.forename: A
authors.initials: A
authors.lastname: Malhotra
authors.forename: J W
authors.initials: JW
authors.lastname: Brown
authors.forename: S C
authors.initials: SC
authors.lastname: Harvey
authors.forename: N R
authors.initials: NR
authors.lastname: Pace
mesh_terms: D000345:Affinity Labels; D001386:Azides / Q000737:chemistry; D001483:Base Sequence; D003198:Computer Simulation; D003432:Cross-Linking Reagents; D004722:Endoribonucleases / Q000737:chemistry* / Q000378:metabolism; D029968:Escherichia coli Proteins; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D012322:RNA Precursors / Q000737:chemistry; D012329:RNA, Bacterial / Q000737:chemistry* / Q000378:metabolism; D016337:RNA, Catalytic / Q000737:chemistry* / Q000378:metabolism; D012343:RNA, Transfer / Q000737:chemistry; D043262:Ribonuclease P; D014466:Ultraviolet Rays
chemical_list: D000345:Affinity Labels; D001386:Azides; D003432:Cross-Linking Reagents; D029968:Escherichia coli Proteins; D012322:RNA Precursors; D012329:RNA, Bacterial; D016337:RNA, Catalytic; D012343:RNA, Transfer; D004722:Endoribonucleases; D043262:Ribonuclease P; C470865:ribonuclease P, E coli