The SH2-domain of SHIP1 interacts with the SHIP1 C-terminus: Impact on SHIP1/Ig-α interaction

► SHIP1 is a crucial negative regulator of B cell antigen receptor signal transduction. ► The SH2-domain of SHIP1 binds to the phospho-ITAM of Ig-α in vitro and in vivo. ► The SH2-domain of SHIP1 binds to the phospho-Y1020 in its C-terminus. ► Thus, SHIP1 is able to dimerize and potentially form larger oligomers. ► This intermolecular interaction of SHIP1 competes against SHIP1/Ig-α interaction.