Product of Saccharomyces cerevisiae nuclear gene PET494 activates translation of a specific mitochondrial mRNA.

AUTOR(ES)

Costanzo, M C

RESUMO

The product of Saccharomyces cerevisiae nuclear gene PET494 is known to be required for a posttranscriptional step in the accumulation of one mitochondrial gene product, subunit III of cytochrome c oxidase (coxIII). Here we show that the PET494 protein probably acts in mitochondria by demonstrating that both a PET494-beta-galactosidase fusion protein and unmodified PET494 are specifically associated with mitochondria. To define the PET494 site of action, we isolated mutations that suppress a pet494 deletion. These mutations were rearrangements of the mitochondrial gene oxi2 that encodes coxIII. The suppressor oxi2 genes had acquired the 5'-flanking sequences of other mitochondrial genes and gave rise to oxi2 transcripts carrying the 5'-untranslated leaders of their mRNAs. These results demonstrate that in wild-type cells PET494 specifically promotes coxIII translation, probably by interacting with the 5'-untranslated leader of the oxi2 mRNA.

Documentos Relacionados

• PET111, a Saccharomyces cerevisiae Nuclear Gene Required for Translation of the Mitochondrial mRNA Encoding Cytochrome c Oxidase Subunit II
• The SPS4 gene of Saccharomyces cerevisiae encodes a major sporulation-specific mRNA.
• The product of the nuclear gene PET309 is required for translation of mature mRNA and stability or production of intron-containing RNAs derived from the mitochondrial COX1 locus of Saccharomyces cerevisiae.
• Pet111 Acts in the 5'-Leader of the Saccharomyces Cerevisiae Mitochondrial Cox2 mRNA to Promote Its Translation
• PDA1 mRNA: a standard for quantitation of mRNA in Saccharomyces cerevisiae superior to ACT1 mRNA.