Rit1, a tRNA backbone-modifying enzyme that mediates initiator and elongator tRNA discrimination.
1994 (English)In: Cell, ISSN 0092-8674, Vol. 79, no 3, 535-546 p.Article in journal (Refereed) Published
Using a genetic screen in yeast aimed at identifying cellular factors involved in initiator and elongator methionine tRNA discrimination in the translational process, we have identified a mutation that abolish the requirement for elongator methionine tRNA. The gene affected, which we call the ribosylation of the initiator tRNA gene or RIT1, encodes a 2'-O-ribosyl phosphate transferase. This enzyme modifies exclusively the initiator tRNA in position 64 using 5'-phosphoribosyl-1'-pyrophosphate as the modification donor. As the initiator tRNA participates both in the initiation and elongation of translation in a rit1 strain, we conclude that the 2'-O-ribosyl phosphate modification discriminates the initiator tRNAs from the elongator tRNAs during protein synthesis. The modification enzyme was shown to recognize the stem-loop IV region that is unique in eukaryotic cytoplasmic initiator tRNAs.
Place, publisher, year, edition, pages
1994. Vol. 79, no 3, 535-546 p.
Biochemistry and Molecular Biology Biochemistry and Molecular Biology
IdentifiersURN: urn:nbn:se:umu:diva-32181PubMedID: 7954819OAI: oai:DiVA.org:umu-32181DiVA: diva2:301469