A conserved and essential basic region mediates tRNA binding to the Elp1 subunit of the Saccharomyces cerevisiae Elongator complex.
Bottom Line: Since these modifications are required for the tRNAs to function efficiently, a translation defect caused by hypomodified tRNAs may therefore underlie the variety of phenotypes associated with Elongator dysfunction.The Elp1 carboxy-terminal domain contains a highly conserved arginine/lysine-rich region that resembles a nuclear localization sequence (NLS).Thus the conserved basic region in Elp1 may be essential for tRNA wobble uridine modification by acting as tRNA binding motif.
Affiliation: Centre for Gene Regulation & Expression, College of Life Sciences, MSI/WTB Complex, University of Dundee, Dundee, DD1 5EH, Scotland, UK.Show MeSH
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Mentions: The yeast Elp1 C-terminal domain contains an Arg/Lys-rich basic region that is highly conserved across eukaryotes (Fig. 1A), implying that it could be functionally important. This region had previously been noted to resemble a putative bipartite NLS (Fichtner et al., 2003), which has the classical consensus sequence (K/R)(K/R)X10–12(K/R)3/5 (Lange et al., 2007; Kosugi et al., 2009). To study the functional significance of this conserved basic region a series of mutations were designed throughout its sequence. A mutant allele (elp1–KR9A) was generated in which nine of the basic residues were substituted by alanine, as well as elp1–KR5A and elp1–KR4A alleles containing alanine substitutions in the first and second halves of the basic region respectively (Fig. 1B). All three mutants were incorporated into the genomic ELP1 locus using the ‘delitto perfetto’ approach.
Affiliation: Centre for Gene Regulation & Expression, College of Life Sciences, MSI/WTB Complex, University of Dundee, Dundee, DD1 5EH, Scotland, UK.