Functional characterization of Caenorhabditis elegans DNA topoisomerase IIIalpha

Nucleic Acids Res. 2000 May 1;28(9):2012-7. doi: 10.1093/nar/28.9.2012.


To investigate the function of a DNA topoisomerase III enzyme in Caenorhabditis elegans, the full-length cDNA of C.elegans DNA topoisomerase IIIalpha was cloned. The deduced amino acid sequence exhibited identities of 48 and 39% with those of human DNA topoisomerase IIIalpha and Saccharomyces cerevisiae DNA topoisomerase III, respectively. The overexpressed polypeptide showed an optimal activity for removing negative DNA supercoils at a relatively high temperature of 52-57 degrees C, which is similar to the optimum temperatures of other eukaryotic DNA topoisomerase III enzymes. When topoisomerase IIIalpha expression was interfered with by a cognate double-stranded RNA injection, pleiotropic phenotypes with abnormalities in germ cell proliferation, oogenesis and embryo-genesis appeared. These phenotypes were well correlated with mRNA expression localized in the meiotic cells of gonad and early embryonic cells.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Caenorhabditis elegans / embryology
  • Caenorhabditis elegans / enzymology
  • Caenorhabditis elegans / genetics*
  • Catalysis
  • Cloning, Molecular
  • DNA Topoisomerases, Type I / genetics*
  • DNA Topoisomerases, Type I / metabolism
  • DNA, Complementary / chemistry
  • DNA, Complementary / genetics
  • Gene Expression Regulation, Developmental
  • Gene Expression Regulation, Enzymologic / drug effects
  • Genes / genetics
  • Glutathione Transferase / genetics
  • Glutathione Transferase / metabolism
  • In Situ Hybridization
  • Molecular Sequence Data
  • RNA, Antisense / administration & dosage
  • RNA, Antisense / genetics
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / metabolism
  • Sequence Analysis, DNA
  • Topoisomerase I Inhibitors


  • DNA, Complementary
  • RNA, Antisense
  • RNA, Messenger
  • Recombinant Fusion Proteins
  • Topoisomerase I Inhibitors
  • Glutathione Transferase
  • DNA Topoisomerases, Type I

Associated data

  • GENBANK/AF057032