Open AccessThe secreted Theileria annulata Ta9 protein contributes to activation of the AP-1 transcription factor
Author(s) -
Ahmet Hakan Ünlü,
Shahin Tajeri,
Hüseyin Bilgin Bilgiç,
Hasan Eren,
Tülin Karagenç,
Gordon Langsley
Publication year - 2018
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0196875
Subject(s) - biology , microbiology and biotechnology , transcription factor , activator (genetics) , theileria , hek 293 cells , mhc class i , transcription (linguistics) , cd8 , gene , antigen , genetics , parasite hosting , linguistics , philosophy , world wide web , computer science
Theileria annulata is an obligate intracellular protozoan parasite of the phylum Apicomplexa . Theileria sporozoites invade bovine leukocytes and develop into a multinucleate syncytial macroschizont that causes uncontrolled proliferation and dissemination of infected and transformed leukocytes. Activator protein 1 (AP-1) is a transcription factor driving expression of genes involved in proliferation and dissemination and is therefore a key player in Theileria -induced leukocytes transformation. Ta9 possesses a signal peptide allowing it to be secreted into the infected leukocyte cytosol and be presented to CD8 T cells in the context of MHC class I. First, we confirmed that Ta9 is secreted into the infected leukocyte cytosol, and then we generated truncated versions of GFP-tagged Ta9 and tested their ability to activate AP-1 in non-infected HEK293T human kidney embryo cells. The ability to activate AP-1-driven transcription was found to reside in the C-terminal 100 amino acids of Ta9 distant to the N-terminally located epitopes recognised by CD8+ T cells. Secreted Ta9 has therefore, not only the ability to stimulate CD8+ T cells, but also the potential to activate AP-1-driven transcription and contribute to T . annulata -induced leukocyte transformation.