Neospora caninum ROP16 play an important role in the pathogenicity by phosphorylating host cell STAT3.

摘要: Neospora caninum is a common cause of abortions in cattle and nervous system dysfunctions dogs. Our analysis shows that NcROP16 TgROP16 have similar structures may functions. To our surprise, we found to the T. gondii RH strain, N. Nc-1 strain could phosphorylate STAT3Y705, but contrast gondii, not STAT6Y641. We constructed gene-knockout plasmid screened ΔNcROP16 strains at gene, protein transcription levels. Plaque assays, invasion assays intracellular proliferation tests indicated phenotypes had changed, resulting smaller plaques slower growth. A virulence showed cerebral loads parasite mice infected with were significantly reduced compared strain. In contrast, overexpression ROP16 led largest number parasites observed mouse brains. Similarly, caused most powerful mice. addition, takes part STAT3 signaling pathway different host cells. This occurs by secretion into cell, where it phosphorylates STAT3, phosphorylated then migrates cell nucleus. can enter nucleus continuously induction apoptosis. The engineered over express induce increased apoptotic-related genes, such as Fas, FasL Bax enhanced ANA1 results show key factor caninum, promoting apoptosis enhancing pathogenicity for phosphorylating STAT3.