Elongator—a tRNA modifying complex that promotes efficient translational decoding

摘要

Naturally occurring modifications of the nucleosides in the anticodon region of tRNAs influence their translational decoding properties. Uridines present at the wobble position in eukaryotic cytoplasmic tRNAs often contain a 5-carbamoylmethyl (ncm5) or 5-methoxycarbonylmethyl (mcm5) side-chain and sometimes also a 2-thio or 2′-O-methyl group. The first step in the formation of the ncm5and mcm5side-chains requires the conserved six-subunit Elongator complex. Although Elongator has been implicated in several different cellular processes, accumulating evidence suggests that its primary, and possibly only, cellular function is to promote modification of tRNAs. In this review, we discuss the biosynthesis and function of modified wobble uridines in eukaryotic cytoplasmic tRNAs, focusing on thein vivorole of Elongator-dependent modifications inSaccharomyces cerevisiae. This article is part of a Special Issue entitled: SI: Regulation of tRNA synthesis and modification in physiological conditions and disease edited by Dr. Boguta Magdalena.