Yeast ribosomal protein S3 has an endonuclease activity on AP DNA

Mol Cells. 2001 Aug 31;12(1):84-90.

Abstract

The mammalian ribosomal protein S3 (rpS3) is a component of the 40S ribosomal subunit. It is known to function as a DNA repair enzyme, UV endonuclease III, which cleaves DNA that is irradiated by UV. It also has an endonuclease activity on AP DNA. In this report, the yeast ribosomal protein S3 (Rps3p) in S. cerevisiae was cloned, expressed in E. coli, and affinity-purified by 285 fold. Rps3p is composed of 240 amino acids and has a 78% amino acid similarity with the human counterpart that has 243 amino acids. The major difference in the amino acid sequence between the two proteins lies in most of the C-terminal 50 residues. Surprisingly, Rps3p only showed an endonuclease activity on AP DNA, but not on DNA that was irradiated with UV. The AP endonuclease activity of Rps3p was affected by pH, KCl, and beta-mercaptoethanol, but Triton X-100 and EDTA did not affect the enzyme activity. From these results, both the mammalian rpS3 and Rps3p appear to be involved in DNA damage processing, but in different modes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Carbon-Oxygen Lyases / metabolism*
  • Cloning, Molecular
  • DNA / metabolism*
  • DNA / radiation effects
  • DNA Repair
  • DNA-(Apurinic or Apyrimidinic Site) Lyase
  • Endodeoxyribonucleases / metabolism*
  • Humans
  • Hydrogen-Ion Concentration
  • Molecular Sequence Data
  • Multienzyme Complexes / metabolism*
  • N-Glycosyl Hydrolases / metabolism*
  • Plasmids
  • Recombinant Fusion Proteins / metabolism
  • Ribosomal Proteins / genetics
  • Ribosomal Proteins / isolation & purification
  • Ribosomal Proteins / metabolism*
  • Saccharomyces cerevisiae / enzymology
  • Saccharomyces cerevisiae / metabolism*
  • Saccharomyces cerevisiae Proteins / genetics
  • Saccharomyces cerevisiae Proteins / isolation & purification
  • Saccharomyces cerevisiae Proteins / metabolism
  • Sequence Alignment

Substances

  • Multienzyme Complexes
  • Recombinant Fusion Proteins
  • Ribosomal Proteins
  • Saccharomyces cerevisiae Proteins
  • ribosomal protein S3
  • UV endonuclease
  • DNA
  • Endodeoxyribonucleases
  • N-Glycosyl Hydrolases
  • Carbon-Oxygen Lyases
  • DNA-(Apurinic or Apyrimidinic Site) Lyase