May play a role in membrane trafficking, specifically in membrane budding reactions. Binds STRN, STRN3 and STRN4. Part of a ternary complex containing MOB4/PHOCN, STRN and/or STRN3 and PPA2. Interacts with DNM1 and EPS15. Interacts with nucleoside diphosphate kinase (By similarity). Interacts with CTTNBP2 and CTTNBP2NL (By similarity). Phosphorylated on serine residues. Belongs to the MOB1/phocein family.