B cell adapter molecule (BAM32) is also designated a dual adapter for phosphotyrosine and 3-phosphotyrosine, and 3-phosphoinositide (DAPP1) or B lymphocyte adapter protein. BAM32 is a B cell-associated adapter that is crucial for B cell antigen receptor signaling regulation. BAM32 interacts with Ptdlns and PLC (gamma)2 and, upon B cell activation, the protein is phosphorylated on tyrosine residues. It is a mainly cytoplasmic protein that can translocate to the cell membrane after cell stimulation. BAM32, which contains one PH domain and one SH2 domain, is primarily expressed in placenta and lung tissues, but can also be detected in heart, liver, pancreas and brain.