title: Lys53 of ribosomal protein L36AL and the CCA end of a tRNA at the P/E hybrid site are in close proximity on the human ribosome.
abstract: Previously we have shown that the CCA end of a P-tRNA can be crosslinked with the RPL36AL protein of the large subunit of mammalian ribosomes; it belongs to the L44e protein family present in all eukaryotic and archaeal ribosomes. Here we confirm and extend this finding and demonstrate that: 1) this crosslink is specific for a tRNA at the P/E hybrid site, as a tRNA in all other tRNA positions of pre-translocational ribosomes could not be crosslinked with a ribosomal protein, 2) the crosslink was formed most efficiently with C74 and C75 of P/E-tRNA, but could also connect the ultimate A of this tRNA with Lys53 of protein RPL36AL, 3) this protein contains seven monomethylated residues (three lysyl and three arginyl residues, as well as glutaminyl residue 51), 4) Q51 is part of a conserved GGQ motif in the L44e proteins in eukaryotic 80S ribosomes that is identical to the universally conserved motif of release factors implicated in promoting peptidyl-tRNA hydrolysis, and 5) the large number of modifications, in which some of the residues were methylated to about 50 %, might indicate that protein RPL36AL is a preferential target for regulation.
authors.affiliation: Equipe de Photobiologie Moléculaire, UPMC Université Paris 06, 2 Place Jussieu, 75252 Paris Cedex 05, France. codjo.hountondji@upmc.fr
authors.forename: Codjo
authors.initials: C
authors.lastname: Hountondji
authors.forename: Konstantin
authors.initials: K
authors.lastname: Bulygin
authors.forename: Anne
authors.initials: A
authors.lastname: Woisard
authors.forename: Pierre
authors.initials: P
authors.lastname: Tuffery
authors.forename: Jean-Bernard
authors.initials: JB
authors.lastname: Créchet
authors.forename: Markus
authors.initials: M
authors.lastname: Pech
authors.forename: Knud H
authors.initials: KH
authors.lastname: Nierhaus
authors.forename: Galina
authors.initials: G
authors.lastname: Karpova
authors.forename: Soria
authors.initials: S
authors.lastname: Baouz
mesh_terms: D020816:Amino Acid Motifs; D000818:Animals; D001665:Binding Sites; D002417:Cattle; D003432:Cross-Linking Reagents; D006801:Humans; D008239:Lysine / Q000737:chemistry* / Q000378:metabolism; D008958:Models, Molecular; D009690:Nucleic Acid Conformation; D011485:Protein Binding; D014176:Protein Biosynthesis; D012346:RNA, Transfer, Amino Acyl / Q000737:chemistry* / Q000378:metabolism; D012269:Ribosomal Proteins / Q000737:chemistry* / Q000378:metabolism; D012270:Ribosomes / Q000737:chemistry* / Q000378:metabolism; D012441:Saccharomyces cerevisiae; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D003432:Cross-Linking Reagents; D012346:RNA, Transfer, Amino Acyl; C471570:RPL36AL protein, human; D012269:Ribosomal Proteins; C019037:tRNA, peptidyl-; D008239:Lysine