Toxoplasma gondii protease TgSUB1 is required for cell surface processing of micronemal adhesive complexes and efficient adhesion of tachyzoites

摘要: Summary Host cell invasion by Toxoplasma gondii is criti- cally dependent upon adhesive proteins secreted from the micronemes. Proteolytic trimming of microneme contents occurs rapidly after their secretion onto parasite surface and pro- posed to regulate complex activation enhance binding host receptors. However, proteases responsible exact function are still unknown. In this report, we show that T. tachyzoites lacking sub- tilisin protease TgSUB1 have a profound defect in processing proteins. Notably parasites lack activity for proteolytic MIC2, MIC4 M2AP release surface. Although complementation with full- length restores processing, complemen- tation Dsub1 GPI anchor (Dsub1::DGPISUB1) only partially protein processing. Loss decreases attachment vitro gliding efficiency leading lower initial rates invasion. Dsub1::DGPISUB1 also less virulent mice. Thus involved micronemal regulation properties macro- molecular complexes