title: Loss of rRNA modifications in the decoding center of the ribosome impairs translation and strongly delays pre-rRNA processing.
abstract: The ribosome decoding center is rich in modified rRNA nucleotides and little is known about their effects. Here, we examine the consequences of systematically deleting eight pseudouridine and 2'-O-methylation modifications in the yeast decoding center. Loss of most modifications individually has no apparent effect on cell growth. However, deletions of 2-3 modifications in the A- and P-site regions can cause (1) reduced growth rates (approximately 15%-50% slower); (2) reduced amino acid incorporation rates (14%-24% slower); and (3) a significant deficiency in free small subunits. Negative and positive interference effects were observed, as well as strong positional influences. Notably, blocking formation of a hypermodified pseudouridine in the P region delays the onset of the final cleavage event in 18S rRNA formation ( approximately 60% slower), suggesting that modification at this site could have an important role in modulating ribosome synthesis.
authors.affiliation: Department of Biochemistry and Molecular Biology, University of Massachusetts, Amherst, Massachusetts 01003, USA.
authors.forename: Xue-Hai
authors.initials: XH
authors.lastname: Liang
authors.forename: Qing
authors.initials: Q
authors.lastname: Liu
authors.forename: Maurille J
authors.initials: MJ
authors.lastname: Fournier
mesh_terms: D001483:Base Sequence; D049109:Cell Proliferation; D025141:Drug Resistance, Fungal / Q000235:genetics; D004526:Efficiency; D008954:Models, Biological; D008958:Models, Molecular; D009154:Mutation / Q000502:physiology; D009690:Nucleic Acid Conformation; D030781:Organisms, Genetically Modified; D014176:Protein Biosynthesis / Q000235:genetics; D012322:RNA Precursors / Q000235:genetics / Q000378:metabolism*; D012323:RNA Processing, Post-Transcriptional / Q000235:genetics* / Q000502:physiology; D012335:RNA, Ribosomal / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D012337:RNA, Ribosomal, 18S / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D012270:Ribosomes / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D015003:Yeasts / Q000235:genetics / Q000378:metabolism
chemical_list: D012322:RNA Precursors; D012335:RNA, Ribosomal; D012337:RNA, Ribosomal, 18S