Molecular cloning of Drosophila mus308, a gene involved in DNA cross-link repair with homology to prokaryotic DNA polymerase I genes

Mol Cell Biol. 1996 Oct;16(10):5764-71. doi: 10.1128/MCB.16.10.5764.


Mutations in the Drosophila mus308 gene confer specific hypersensitivity to DNA-cross-linking agents as a consequence of defects in DNA repair. The mus308 gene is shown here to encode a 229-kDa protein in which the amino-terminal domain contains the seven conserved motifs characteristic of DNA and RNA helicases and the carboxy-terminal domain shares over 55% sequence similarity with the polymerase domains of prokaryotic DNA polymerase I-like enzymes. This is the first reported member of this family of DNA polymerases in a eukaryotic organism, as well as the first example of a single polypeptide with homology to both DNA polymerase and helicase motifs. Identification of a closely related gene in the genome of Caenorhabditis elegans suggests that this novel polypeptide may play an evolutionarily conserved role in the repair of DNA damage in eukaryotic organisms.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Bacillus / enzymology
  • Caenorhabditis elegans / enzymology
  • Caenorhabditis elegans / genetics
  • Cloning, Molecular
  • DNA Helicases / chemistry
  • DNA Polymerase I / biosynthesis
  • DNA Polymerase I / chemistry
  • DNA Polymerase I / genetics*
  • DNA Repair Enzymes
  • DNA Repair*
  • DNA-Directed DNA Polymerase
  • Drosophila Proteins*
  • Drosophila melanogaster / enzymology
  • Drosophila melanogaster / genetics*
  • Escherichia coli / enzymology
  • Genes, Insect*
  • Models, Structural
  • Molecular Sequence Data
  • Protein Structure, Secondary*
  • Recombinant Proteins / biosynthesis
  • Recombinant Proteins / chemistry
  • Saccharomyces cerevisiae / enzymology
  • Sequence Homology, Amino Acid
  • Streptococcus pneumoniae / enzymology


  • Drosophila Proteins
  • Recombinant Proteins
  • DNA Polymerase I
  • DNA-Directed DNA Polymerase
  • DNApol-theta protein, Drosophila
  • DNA Helicases
  • DNA Repair Enzymes

Associated data

  • GENBANK/D29641
  • GENBANK/D31241
  • GENBANK/D35423
  • GENBANK/D36993
  • GENBANK/D37217
  • GENBANK/D64204
  • GENBANK/D67135
  • GENBANK/D68935
  • GENBANK/L76559
  • GENBANK/P32639
  • GENBANK/P35207
  • GENBANK/U00066
  • GENBANK/U09877
  • GENBANK/U20861
  • GENBANK/U22156
  • GENBANK/U35242
  • GENBANK/U42580
  • GENBANK/U50184
  • GENBANK/Z42372
  • GENBANK/Z49325