Heterodimer with AMPH. Binds SH3GLB1 (By similarity). Interacts (via SH3 domain) with SYNJ1. Interacts (via SH3 domain) with DNM1. Isoform IIA interacts with CLTC. Isoform IIB does not interact with CLTC. Isoform IIC1 does not interact with CLTC. Isoform IIC2 does not interact with CLTC. Interacts with AP2A2. Interacts with AP2B1. Interacts with MYC (via N-terminal transactivation domain); the interaction requires the integrity of the conserved MYC box regions 1 and 2. Interacts with BIN2. Interacts (SH3 domain) with HCV NS5A.