Human SH2D1A Antibody

SH2D1A (Src-Homology 2 Domain-Containing protein A1; also SAP and DSHP) is a 15-19 kDa protein that represents the product of the XLP (X-linked Lymphoproliferative Disease) gene. It is a cytoplasmic protein that is expressed in T cells, NK cells, and memory B cells. SH2D1A interacts with the SH2 binding domains of at least six SLAM family cell membrane proteins, including Ly9, CD84, 2B4/CD244, NTBA, CS1 and SLAM/CD150. This has the effect of blocking an SHP2 interaction with the above phosphorylated receptors and abrogating downstream signaling. Notably, SH2D1A also recruits and activates the Src kinase Fyn when bound to SLAM family molecules, and this action presumably impacts additional downstream signaling. Human SH2D1A is 128 amino acids (aa) in length. Although it contains only one SH2 domain (aa 6-104), this domain can be utilized simultaneously by SLAM and Fyn, creating a trimeric complex. There are multiple splice variants for SH2D1A. One shows a three aa deletion of aa 114-116, a second possesses a nine aa substitution for aa 68-128, a third contains a 16 aa substitution for aa 47-128, a fourth possesses a 12 aa substitution for aa 47-128, while a fifth contains a 37 aa substitution for aa 40-128. Full length human SH2D1A shares 88% aa identity with mouse SH2D1A.