Repression of does not contribute to the synthetic growth defect conferred by an -marked deletion of in a mutant.

Powers et al. recently demonstrated that the cassette used to delete in yeast mutants leads to reduced expression in of the adjacent gene encoding the mitochondrial small subunit (SSU) ribosomal protein Mrp51. Here we provide evidence that elimination of Dbp1, not reduced expression, underlies the synthetic growth defect of a mutant on glucose-containing medium, where respiration is dispensable, consistent with our previous conclusion that Dbp1 and Ded1 perform overlapping functions in stimulating translation initiation on mRNAs burdened with long or structured 5'UTRs in cells cultured with glucose.