Characterisation of the TA15705 protein of Theileria annulata and determination of its role in AP-1 activation

Theileria annulata is an obligate intracellular protozoa parasite of the phylum apicomplexa. T. annulata causes tropical theiloriosis in cattle and is transmitted by the ticks of the genus Hyalomma. Theileria sporozoites invade bovine leukocytes, develop into a multinucleate syncytial schizont form and alter the metabolic activity of the infected host cell. Infected leukocytes do not undergo apoptosis and display uncontrolled proliferation like cancer cells.AP-1 is a transcription factor that controls a number of cellular processes including differantiation, proliferation and apoptosis. AP-1 plays a role in cell transformation in Theileria infected leukocytes.TA15705 protein also known as Ta9 expressed at T. annulata macroschizont is a target of cytotoxic T cells and B cells. The study was carried out between September 2008 and October 2009 to characterise the TA15705 protein and determine its role in parasite-induced AP-1 activation. In the present, it was shown that TA15705 was an inducer of AP-1 which plays a role in transformation event of infected cells. It was also demonstrated that TA15705 was co-localises with the parasite and secreted into the cytosol of infected B lymphocytes and macrophages.Keywords: TA15705, AP-1, Theileria annulata, Apoptosis