Background of the antigen
B cell adaptor for phosphoinositide 3-kinase (BCAP) is a tyrosine kinase substrate that bridges B cell receptor (BCR) associated kinases to the PIK3 pathway. Syk, Btk or Lyn-dependent tyrosine phosphorylation of BCAP, provides binding sites for the p85 subunit of PIK3. BCAP mRNA is present in mouse spleen, thymus, liver, lung, macrophage and B cell lines. Human BCAP maps to chromosome 10q24.2.