Overproduction of EF-1A suppresses RTD in a tan1-Δ trm44-Δ mutant. (A) Overproduction of TEF1 or TEF2 partially suppresses the temperature-sensitive phenotype of tan1-Δ trm44-Δ mutants. Strains with MORF plasmids expressing TEF1 or TEF2 (or a vector control) were grown and plated on YP media containing raffinose and galactose as described in Figure 1A. (B) Overproduction of TEF1 prevents degradation of tRNASer(CGA) and tRNASer(UGA) in tan1-Δ trm44-Δ mutants. Strains were grown at 28°C, treated with thiolutin (TL), and shifted to 36°C for the times indicated, and RNA was extracted, resolved by PAGE, transferred, and hybridized. RNA levels were quantified by normalizing to 5.8 S RNA levels and then normalizing to the values in the wild type (BY4741) at time zero. Diamonds indicate wild type; open squares, tan1-Δ trm44-Δ; and triangles, tan1-Δ trm44-Δ [TEF1].
