title: Photocrosslinking of thiolated aminoacyl-tRNA to ribosomal RNA and proteins.
abstract: tRNA has been converted to a form that can be photoactivated by chemical modification of some of the exposed cytidine residues to thio-4-uridine A certain percentage of the modified molecules can be charged and bound to the ribosome; thiolated fMet-tRNAfMet is bound to the P-site as shown by puromycin reactivity. Near the UV irradiation produces covalent crosslinks between total thiolated AA-tRNA or fMet-tRNAfMet and the ribosome. AA-tRNA becomes crosslinked to both 30S and 50S subunits but fMet-tRNAfMet to 50S subunits alone. In each case, crosslinking of tRNA was found to be not only to ribosomal proteins, but also to rRNA. The covalent complexes appear sufficiently stable to allow identification of the proteins or rRNA sequences involved.
mesh_terms: D004926:Escherichia coli; D012335:RNA, Ribosomal / Q000378:metabolism* / Q000528:radiation effects; D012346:RNA, Transfer, Amino Acyl / Q000378:metabolism* / Q000528:radiation effects; D012358:RNA, Transfer, Met; D012269:Ribosomal Proteins / Q000378:metabolism* / Q000528:radiation effects; D013891:Thiouridine / Q000378:metabolism; D014466:Ultraviolet Rays
chemical_list: D012335:RNA, Ribosomal; D012346:RNA, Transfer, Amino Acyl; D012358:RNA, Transfer, Met; D012269:Ribosomal Proteins; C024988:tRNA, formylmethionine-; D013891:Thiouridine