Hungry codons promote frameshifting in human mitochondrial ribosomes.
Human mitochondria are not strict adherents to the universal genetic code, with modifications that include the apparent recoding of two arginine triplets to termination signals. This use of both AGA and AGG occurs rarely in other mammals, and this putative change has long posed a challenging conundrum. A -1 mitoribosome frameshift upstream of the rare codons would necessitate recognition of only the conventional UAA and UAG termination codons. By using a sequence-specific endoribonuclease, we show that the rare arginine codons, presumably in association with other cis elements, promote frameshifting in human mitoribosomes.
Temperley
Richard
R
The Mitochondrial Research Group, Institute for Ageing and Health, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4HH, UK.
Richter
Ricarda
R
Dennerlein
Sven
S
Lightowlers
Robert N
RN
Chrzanowska-Lightowlers
Zofia M
ZM
D020413:3' Untranslated Regions; D001120:Arginine / Q000235:genetics; D018388:Codon, Terminator / Q000235:genetics*; D004722:Endoribonucleases / Q000378:metabolism; D018965:Frameshifting, Ribosomal; D050259:Genes, Mitochondrial; D006801:Humans; D008928:Mitochondria / Q000235:genetics* / Q000648:ultrastructure; D024101:Mitochondrial Proteins / Q000235:genetics / Q000378:metabolism; D016366:Open Reading Frames; D010454:Peptide Termination Factors / Q000235:genetics / Q000378:metabolism; D012313:RNA / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism*; D000077278:RNA, Mitochondrial; D012270:Ribosomes / Q000235:genetics* / Q000378:metabolism
D020413:3' Untranslated Regions; D018388:Codon, Terminator; C523958:MTRF1L protein, human; D024101:Mitochondrial Proteins; D010454:Peptide Termination Factors; D012333:RNA, Messenger; D000077278:RNA, Mitochondrial; D012313:RNA; D001120:Arginine; D004722:Endoribonucleases