The yeast ORF YDL202w codes for the mitochondrial ribosomal protein YmL11

Abstract

The Saccharomyces cerevisiae open reading frame YDL202w has been characterised in the course of the EUROFAN yeast genome analysis program. Disruption of YDL202w causes a respiratory deficient phenotype accompanied by a loss of mitochondrial DNA. This phenotype is usually found in mutants defective in mitochondrial replication or gene expression. YDL202w 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 predicted amino-acid sequence of YDL202w starts with a stretch which has neither any correspondence in the bacterial sequences nor in the protein isolated from mitochondrial ribosomes. Furthermore, this stretch matches the requirements for a signal sequence for mitochondrial protein import. A mitochondrial location of the YDL202w gene product was proven by use of a carboxy terminally HA-tagged version. These findings clearly indicate that YDL202w encodes this mitochondrial ribosomal protein (YmL11).