SH2 Domain Containing 1a (SH2D1A) Human Recombinant Protein

This gene encodes a protein that plays a major role in the bidirectional stimulation of T and B cells. This protein contains an SH2 domain and a short tail. It associates with the signaling lymphocyte-activation molecule, thereby acting as an inhibitor of this transmembrane protein by blocking the recruitment of the SH2-domain-containing signal-transduction molecule SHP-2 to its docking site. This protein can also bind to other related surface molecules that are expressed on activated T, B and NK cells, thereby modifying signal transduction pathways in these cells. Mutations in this gene cause lymphoproliferative syndrome X-linked type 1 or Duncan disease, a rare immunodeficiency characterized by extreme susceptibility to infection with Epstein-Barr virus, with symptoms including severe mononucleosis and malignant lymphoma. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jul 2008]

SH2D1A: Inhibitor of the SLAM self-association. Acts by blocking recruitment of the SH2-domain-containing signal-transduction molecule SHP-2 to a docking site in the SLAM cytoplasmic region. Mediates interaction between FYN and SLAMF1. May also regulate the activity of the neurotrophin receptors NTRK1, NTRK2 and NTRK3. Interacts with NTRK1, NTRK2 and NTRK3. Interacts with CD84, CD244, LY9, SLAMF1 and FYN. Expressed at a high level in thymus and lung, with a lower level of expression in spleen and liver. Expressed in peripheral blood leukocytes, including T lymphocytes. Tends to be expressed at lower levels in peripheral blood leukocytes in patients with rheumatoid arthritis. 6 isoforms of the human protein are produced by alternative splicing.

Protein type: Apoptosis; Adaptor/scaffold

Chromosomal Location of Human Ortholog: Xq25

Cellular Component: cytoplasm

Molecular Function: protein binding; SH3/SH2 adaptor activity

Biological Process: cell-cell signaling; positive regulation of signal transduction; cellular defense response; positive regulation of natural killer cell mediated cytotoxicity; humoral immune response

Disease: Lymphoproliferative Syndrome, X-linked, 1