Characterisation of a DM domain-containing transcription factor from Trichostrongylus vitrinus (Nematoda: Strongylida)

The sequence and expression profile of Tv-mab-23, a gene encoding a DM domain-containing protein from the parasitic nematode Trichostrongylus vitrinus, were investigated. The gene, containing an open reading frame (ORF) of 537 bp, encoded a predicted protein which had an overall amino acid identity of 45% to the MAB-23 molecule of the free-living nematode Caenorhabditis elegans. High levels of conservation were particularly predominant at the amino terminus of the proteins, with 86% identity over the first 58 amino acid residues in a region containing the highly conserved zinc module of the DM domain and conserved regions of the recognition helix of DM domain-containing transcription factors. Tv-mab-23 was expressed in a stage-specific manner in T. vitrinus. The highest levels of expression in fourth stage larvae coincide with the period in which profound gender-specific alterations in physiology occur in both the parasitic and free-living nematodes.