Screening and identification of Theileria annulata proteins interacting with bovine TFG proteins

Int J Biol Macromol. 2025 Jun 25:145516. doi: 10.1016/j.ijbiomac.2025.145516. Online ahead of print.

Abstract

Bovine monocytes infected with Theileria annulata (T. annulata) could proliferate indefinitely in vitro, and the expression of Tropomyosin-receptor fused gene (TFG) increased accordingly. At present, the molecular mechanism of regulation of host cell transformation by T. annulata protein binding TFG protein is still not fully determined. Therefore, this study aimed to screen T. annulata protein, which interacts with TFG, to explore the molecular mechanism of T. annulata regulating bovine monocyte transformation. T. annulata protein interacting with TFG protein was screened and identified by yeast two-hybrid (Y2-H), co-immunoprecipitation (Co-IP) and confocal analysis. After overexpression of TFG and TA11965 in transformed cells by lentiviral packaging technology, flow cytometry detected the host cell cycle and apoptosis. The results showed that Ta11965 interacted with bovine TFG protein. In addition, overexpression of Ta11965 inhibited apoptosis, promoted cell proliferation, and upregulated the mRNA and protein levels of TFG. Similarly, overexpression of TFG in transformed cells of T. annulata inhibited apoptosis and stimulated cell proliferation. In the above experiments, we systematically screened and validated Ta11965, a T. annulata protein interacting with bovine TFG protein, and revealed the regulatory mechanism by which Ta11965 in host cell transformation. These findings will lay the foundation for studying the molecular mechanism of the pathogenesis of T. annulata.

Keywords: Apoptosis; Bovine TFG protein; Co-immunoprecipitation; Proliferation; Theileria annulata; Yeast two-hybrid.