THE YEAST ORF YDL202W CODES FOR THE MITOCHONDRIAL RIBOSOMAL-PROTEIN YML11

The Saccharomyces cerevisiae open reading frame YDL202w has been chara cterised in the course of the EUROFAN yeast genome analysis program. D isruption of YDL202w causes a respiratory deficient phenotype accompan ied by a loss of mitochondrial DNA. This phenotype is usually found in mutants defective in mitochondrial replication or gene expression. YD L202w has the potential to encode a soluble protein of 249 amino acids . It shows significant similarities to the ribosomal protein L10 from various bacteria and to a previously determined amino-terminal peptide sequence of the yeast mitochondrial ribosomal protein L11. The predic ted amino-acid sequence of YDL202w starts with a stretch which has nei ther any correspondence in the bacterial sequences nor in the protein isolated from mitochondrial ribosomes. Furthermore, this stretch match es the requirements for a signal sequence for mitochondrial protein im port. A mitochondrial location of the YDL202w gene product was proven by use of a carboxy terminally HA-tagged version. These findings clear ly indicate that YDL202w encodes this mitochondrial ribosomal protein (YmL11).