REQUIREMENT OF THE DEAD-BOX PROTEIN DED1P FOR MESSENGER-RNA TRANSLATION

The DED1 gene, which encodes a putative RNA helicase, has been implica ted in nuclear pre-messenger RNA splicing in the yeast Saccharomyces c erevisiae. It is shown here by genetic and biochemical analysis that t ranslation, rather than splicing, is severely impaired in two newly is olated ded1 conditional mutants, Preliminary evidence suggests that th e protein Ded1p may be required for the initiation step of translation , as is the distinct DEAD-box protein, eukaryotic initiation factor 4A (eIF4A), The DED1 gene could be functionally replaced by a mouse homo log, PL10, which suggests that the function of Ded1p in translation is evolutionarily conserved.