YmL9, a nucleus-encoded mitochondrial ribosomal protein of yeast, is homologous to L3 ribosomal proteins from all natural kingdoms and photosynthetic organelles

Eur J Biochem. 1992 Jun 1;206(2):373-80. doi: 10.1111/j.1432-1033.1992.tb16937.x.


The nuclear gene for mitochondrial ribosomal protein YmL9 (MRP-L9) of yeast has been cloned and sequenced. The deduced amino acid sequence characterizes YmL9 as a basic (net charge + 30) protein of 27.5 kDa with a putative signal peptide for mitochondrial import of 19 amino acid residues. The intact MRP-L9 gene is essential for mitochondrial function and is located on chromosome XV or VII. YmL9 shows significant sequence similarities to Escherichia coli ribosomal protein L3 and related proteins from various organisms of all three natural kingdoms as well as photosynthetic organelles (cyanelles). The observed structural conservation is located mostly in the C-terminal half and is independent of the intracellular location of the corresponding genes [Graack, H.-R., Grohmann, L. & Kitakawa, M. (1990) Biol. Chem. Hoppe Seyler 371, 787-788]. YmL9 shows the highest degree of sequence similarity to its eubacterial and cyanelle homologues and is less related to the archaebacterial or eukaryotic cytoplasmic ribosomal proteins. Due to their high sequence similarity to the YmL9 protein two mammalian cytoplasmic ribosomal proteins [MRL3 human and rat; Ou, J.-H., Yen, T. S. B., Wang, Y.-F., Kam, W. K. & Rutter, W. J. (1987) Nucleic Acids Res. 15, 8919-8934] are postulated to be true nucleus-encoded mitochondrial ribosomal proteins.

MeSH terms

  • Amino Acid Sequence
  • Base Sequence
  • Cell Nucleus / metabolism
  • Chromosome Mapping
  • Chromosomes, Fungal
  • Cloning, Molecular
  • DNA, Fungal
  • Electrophoresis, Agar Gel
  • Escherichia coli / metabolism
  • Fungal Proteins / genetics*
  • Mitochondria / metabolism*
  • Mitochondrial Proteins
  • Molecular Sequence Data
  • Organelles / metabolism*
  • Photosynthesis*
  • Protein Sorting Signals / genetics
  • Restriction Mapping
  • Ribosomal Protein L3
  • Ribosomal Proteins / genetics*
  • Saccharomyces cerevisiae / metabolism*
  • Saccharomyces cerevisiae Proteins*
  • Sequence Alignment
  • Sequence Homology, Nucleic Acid


  • DNA, Fungal
  • Fungal Proteins
  • MRPL9 protein, S cerevisiae
  • Mitochondrial Proteins
  • Protein Sorting Signals
  • RPL3 protein, human
  • Ribosomal Protein L3
  • Ribosomal Proteins
  • Saccharomyces cerevisiae Proteins

Associated data

  • GENBANK/S87180
  • GENBANK/S87218
  • GENBANK/S87221
  • GENBANK/S87223
  • GENBANK/X65014
  • GENBANK/X65121
  • GENBANK/X65178
  • GENBANK/X65179
  • GENBANK/X65180
  • GENBANK/X65181