B-cell antigen receptor complex-associated protein beta chain (CD79B)

Required in collaboration with CD79A for initiation of the signal transduction cascade triggered by the B-cell antigen receptor complex (BCR) which contributes to internalization of the complex, trafficking to late endosomes and antigen presentation. Improves phosphorylation of CD79A, possibly by recruiting kinases which phosphorylate CD79A or by recruiting proteins which bind to CD79A and protect it from dephosphorylation.