A proposed model for MoEnd3 function.

During germ tube development, GPCR Pth11 and membrane sensor MoSho1 are regulated by MoEnd3-mediated endocytosis. MoEnd3 function in endocytosis is negatively regulated by MoArk1-initiated phosphorylation, leading to an efficient endocytosis. Following transport to endosomal systems by endocytic vesicles, Pth11 and MoSho1 can trigger a downstream MAPK cascade, consisting of Mst11, Mst7, Pmk1 and adaptor Mst50. The MAPK cascade facilitates successful nuclear degradation/autophagy, appressorium formation, penetration and pathogenicity. In addition, MoEnd3 is also involved in an endocytosis/exocytosis coupling pathway to facilitate effector secretion and biotrophic growth.