TRANSMEMBRANE SIGNALING BY THE B-CELL ANTIGEN RECEPTOR

Crosslinking the B-cell antigen receptor is sufficient to generate int racellular signals. Recent work has shown that this signalling capabil ity can be ascribed to the presence of the alpha and beta sheath prote ins within the antigen receptor that couple it to signal transduction pathways. However, a variety of other transmembrane proteins, includin g CD19, CD21, CD22, CD32 and CD45, can also associate with the recepto r and we are beginning to understand how they may act in concert with it to efficiently regulate B lymphocyte activity in response to antige n.