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. Interacts with CTTNBP2. Interacts with CTTNBP2NL (By similarity). Detected in cell bodies and dendrites of neurons, but not in axons. Highly expressed in adrenal gland, spinal cord, brain and cerebellum. Detected at lower levels in heart and skeletal muscle, and at very low levels in spleen, liver and intestine. Phosphorylated on serine residues. Belongs to the MOB1/phocein family.