The Toxoplasma nuclear factor TgAP2XI-4 controls bradyzoite gene expression and cyst formation

Robert Walker, Mathieu Gissot, Matthew M. Croken, Ludovic Huot, David Hot, Kami Kim, Stanislas Tomavo

Research output: Contribution to journalArticle

41 Citations (Scopus)

Abstract

Toxoplasma gondii undergoes many phenotypic changes during its life cycle. The recent identification of AP2 transcription factors in T.gondii has provided a platform for studying the mechanisms controlling gene expression. In the present study, we report that a recombinant protein encompassing the TgAP2XI-4 AP2 domain was able to specifically bind to a DNA motif using gel retardation assays. TgAP2XI-4 protein is localized in the parasite nucleus throughout the tachyzoite life cycle in vitro, with peak expression occurring after cytokinesis. We found that the TgAP2XI-4 transcript level was higher in bradyzoite cysts isolated from brains of chronically infected mice than in the rapidly replicating tachyzoites. A knockout of the TgAP2XI-4 gene in both T.gondii virulent type I and avirulent type II strains reveals its role in modulating expression and promoter activity of genes involved in stage conversion of the rapidly replicating tachyzoites to the dormant cyst forming bradyzoites. Furthermore, mice infected with the type II KO mutants show a drastically reduced brain cyst burden. Thus, our results validate TgAP2XI-4 as a novel nuclear factor that regulates bradyzoite gene expression during parasite differentiation and cyst formation.

Original languageEnglish (US)
Pages (from-to)641-655
Number of pages15
JournalMolecular Microbiology
Volume87
Issue number3
DOIs
StatePublished - Feb 2013

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Toxoplasma
Cysts
Gene Expression
Life Cycle Stages
Parasites
Transcription Factor AP-2
Nucleotide Motifs
Cytokinesis
Brain
Electrophoretic Mobility Shift Assay
Recombinant Proteins
Genes
Proteins

ASJC Scopus subject areas

  • Molecular Biology
  • Microbiology

Cite this

Walker, R., Gissot, M., Croken, M. M., Huot, L., Hot, D., Kim, K., & Tomavo, S. (2013). The Toxoplasma nuclear factor TgAP2XI-4 controls bradyzoite gene expression and cyst formation. Molecular Microbiology, 87(3), 641-655. https://doi.org/10.1111/mmi.12121

The Toxoplasma nuclear factor TgAP2XI-4 controls bradyzoite gene expression and cyst formation. / Walker, Robert; Gissot, Mathieu; Croken, Matthew M.; Huot, Ludovic; Hot, David; Kim, Kami; Tomavo, Stanislas.

In: Molecular Microbiology, Vol. 87, No. 3, 02.2013, p. 641-655.

Research output: Contribution to journalArticle

Walker, R, Gissot, M, Croken, MM, Huot, L, Hot, D, Kim, K & Tomavo, S 2013, 'The Toxoplasma nuclear factor TgAP2XI-4 controls bradyzoite gene expression and cyst formation', Molecular Microbiology, vol. 87, no. 3, pp. 641-655. https://doi.org/10.1111/mmi.12121
Walker, Robert ; Gissot, Mathieu ; Croken, Matthew M. ; Huot, Ludovic ; Hot, David ; Kim, Kami ; Tomavo, Stanislas. / The Toxoplasma nuclear factor TgAP2XI-4 controls bradyzoite gene expression and cyst formation. In: Molecular Microbiology. 2013 ; Vol. 87, No. 3. pp. 641-655.
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