TIGIT
TIGIT (T cell immunoreceptor with Ig and ITIM domains) is an inhibitory receptor on the cell membrane that modulates immune responses. It is also known as VSIG9 or VSTM3 and acts on T cells and NK cells. Browse Assay Genie's current range of TIGIT research reagents below, or read on for the biology behind the target.
TIGIT is an inhibitory receptor that helps modulate immune responses. It suppresses T-cell activation by promoting the generation of mature immunoregulatory dendritic cells. Its ligands, PVR (CD155) and NECTIN2 (CD112), are expressed on antigen-presenting cells. When a ligand binds, TIGIT sends an inhibitory signal to the T cell or NK cell. TIGIT also acts as a receptor for NECTIN4, through which it inhibits NK cell cytotoxicity.
The signalling mechanism is described in some detail. Ligand engagement leads Src family tyrosine kinases such as FYN or LCK to phosphorylate the cytoplasmic tail. This allows the adapter GRB2 and SHIP1 (INPP5D) to bind, and in turn inhibits the PI3K and MAPK signalling cascades. TIGIT also associates with beta-arrestin-2 (ARRB2) to recruit SHIP1. This suppresses autoubiquitination of TRAF6 and inhibits the NF-kappa-B signalling pathway.
The TIGIT gene encodes a member of the PVR (poliovirus receptor) family of immunoglobulin proteins, and HGNC places it in the V-set domain containing group. The protein is expressed on several classes of T cells, including follicular B helper T cells (TFH). It binds PVR with high affinity, and this binding is thought to assist interactions between TFH and dendritic cells to regulate T cell-dependent B cell responses. Earlier names for the gene include VSIG9 and VSTM3. The mouse ortholog is Tigit.
TIGIT is an inhibitory receptor that suppresses T-cell activation and sends inhibitory signals to T cells and NK cells when bound to its ligands.
TIGIT inhibits NK cell cytotoxicity on binding NECTIN4, and signals to NK cells through PVR and NECTIN2.
TIGIT engagement recruits GRB2, SHIP1 and beta-arrestin-2 to inhibit PI3K, MAPK and NF-kappa-B signalling, making it a model for inhibitory receptor pathways.
TIGIT is expressed on follicular B helper T cells and is thought to shape their interactions with dendritic cells to regulate B cell responses.
TIGIT is an inhibitory receptor that modulates immune responses. When it binds PVR/CD155 or NECTIN2/CD112 on antigen-presenting cells, it sends inhibitory signals to T cells or NK cells. It also suppresses T-cell activation by promoting mature immunoregulatory dendritic cells.
The full name is T cell immunoreceptor with Ig and ITIM domains. Previous gene names are VSIG9 and VSTM3, and other aliases include FLJ39873 and DKFZp667A205. Searching under any of these should reach the same TIGIT gene and protein.
A mouse ortholog, Tigit, is recorded for this gene, which allows comparative work in mouse models. No rat ortholog is listed in the data used here. Check the datasheet of any product for its validated reactivity.
Ligands, adapters and kinases in the TIGIT inhibitory signalling pathway, with products at Assay Genie.
Gene and protein annotations from HGNC, NCBI Gene and UniProt Q495A1; product specifications from Assay Genie datasheets.