The hSNM1 protein is a DNA 5'-exonuclease

Nucleic Acids Res. 2007;35(18):6115-23. doi: 10.1093/nar/gkm530. Epub 2007 Sep 5.

Abstract

The human SNM1 protein is a member of a highly conserved group of proteins catalyzing the hydrolysis of nucleic acid substrates. Although overproduction is unstable in mammalian cells, we have overproduced a recombinant hSNM1 protein in an insect cell system. The protein is a single-strand 5'-exonuclease, like its yeast homolog. The enzyme utilizes either DNA or RNA substrates, requires a 5'-phosphate moiety, shows very little activity on double-strand substrates, and functions at a size consistent with a monomer. The exonuclease activity requires the conserved beta-lactamase domain; site-directed mutagenesis of a conserved aspartate inactivates the exonuclease.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Aspartic Acid / genetics
  • Cell Line
  • DNA Repair Enzymes / chemistry
  • DNA Repair Enzymes / genetics
  • DNA Repair Enzymes / metabolism*
  • DNA, Single-Stranded / metabolism
  • Drosophila melanogaster / cytology
  • Endodeoxyribonucleases / metabolism
  • Exodeoxyribonucleases / chemistry
  • Exodeoxyribonucleases / genetics
  • Exodeoxyribonucleases / metabolism*
  • Fibroblasts / metabolism
  • Humans
  • Mutagenesis, Site-Directed
  • Nuclear Proteins / chemistry
  • Nuclear Proteins / genetics
  • Nuclear Proteins / metabolism*
  • Phosphates / metabolism

Substances

  • DNA, Single-Stranded
  • Nuclear Proteins
  • Phosphates
  • Aspartic Acid
  • DCLRE1B protein, human
  • Endodeoxyribonucleases
  • Exodeoxyribonucleases
  • DNA Repair Enzymes