Identification of novel bradyzoite-specific genes with domains for protein-protein interactions

Mol Biochem Parasitol. 2007 Oct 24 [Epub ahead of print]

Identification of novel bradyzoite-specific Toxoplasma gondii genes with domains for protein-protein interactions by suppression subtractive hybridization

Friesen J, Fleige T, Gross U, Bohne W

Institute of Medical Microbiology, University of Göttingen, Kreuzbergring 57, Göttingen D-37075, Germany.

By using suppression subtractive hybridization we identified five so far uncharacterized stage specific genes in Toxoplasma gondii, which are induced during tachyzoite-to-bradyzoite differentiation. The mRNA level of a putative zinc-finger protein was increased 23-fold in bradyzoites, while the remaining four genes displayed induction levels >100-fold. Two of these genes predict proteins with domains for protein-protein interactions. One protein (ANK1) contains both, a TPR-domain and an ankyrin motif, which consists of seven repeats. ANK1 was shown by epitope tagging experiments to be localized in the cytosol. In a fraction of parasites, the myc-tagged fusion protein was additionally localized in the nucleus, which is in agreement with the presence of a bipartite nuclear targeting sequence in ANK1. The identification of bradyzoite-specific proteins with TPR- and ankyrin-domains supports the concept that during stage conversion a variety of proteins which are involved in protein-protein interactions are induced, thereby assisting the rebuilding of the proteome.

PMID: 18061287 [PubMed - as supplied by publisher]