THE PROTEIN ENCODED BY THE MFT1 GENE IS A TARGETING FACTOR FOR MITOCHONDRIAL PRECURSOR PROTEINS, AND NOT A CORE RIBOSOMAL-PROTEIN

Yeast cells harboring mft1 mutations are compromised in mitochondrial protein targeting, and Mft1p has previously been identified as a ribos omal protein, However, two genes, PLC2 and YML062C, are present in the MFT1 locus, and we show that mft1 mutant cells are compromised in the function of the cytosolic protein encoded by YML062C, The ribosomal p rotein (YS3a) is actually encoded by the tightly linked PLC2 gene, and does not play a role in targeting proteins to the mitochondria. (C) 1 997 Federation of European Biochemical Societies.