Fig. 8.

Model of TAT-5 trafficking to inhibit EV release. TAT-5 maintains PE asymmetry in the plasma membrane to inhibit recruitment of the ESCRT machinery to release EVs by plasma membrane budding. PAD-1 is required for TAT-5 flippase activity, which inhibits the externalization of PE and EV release. TAT-5 is endocytosed and needs to be recycled from sorting endosomes to the plasma membrane through both SNX-1–SNX-6–mediated and SNX-3–mediated tubulation and vesicle formation. RME-8 and PI3K mediate TAT-5 recycling through multiple pathways. MON-2 and PAD-1 regulate an unknown step of endosomal trafficking, here drawn as a third recycling pathway preventing membrane cargos from being delivered to multivesicular endosomes for degradation. When both SNX-mediated recycling and MON-2/PAD-1–mediated trafficking are lost, TAT-5 is mislocalized to late endosomes where it can no longer maintain plasma membrane asymmetry.