VSIG4
VSIG4, also known as Z39IG or CRIg, is a membrane protein with a V-set immunoglobulin domain that acts as a phagocytic receptor and a negative regulator of T-cell responses. It also binds the complement fragments C3b and iC3b and inhibits the alternative complement pathway. Browse Assay Genie's current range of VSIG4 research reagents below, or read on for the biology behind the target.
VSIG4 (V-set and immunoglobulin domain containing 4) is a phagocytic receptor that sits at the interface between innate and adaptive immunity. UniProt describes it as a strong negative regulator of T-cell proliferation and of IL2 production, and as a potent inhibitor of the alternative complement pathway convertases. It is also a receptor for the complement component 3 fragments C3b and iC3b, which links it directly to complement-mediated recognition.
The VSIG4 gene encodes a V-set and immunoglobulin-domain containing protein that is structurally related to the B7 family of immune regulatory proteins. This relationship to the B7 family is consistent with its proposed role as a negative regulator of T-cell responses. Alternate splicing of the gene results in multiple transcript variants. The VSIG4 protein is a membrane protein, and it is the form at the cell surface that engages complement fragments and takes part in phagocytosis.
HGNC places VSIG4 in two gene groups: V-set domain containing proteins, and complement system regulators and receptors. The alias CRIg is commonly used in the literature, and Z39IG is a further alias. Together these groupings reflect the dual nature of the protein. It acts as a complement receptor and regulator, and it also shares features with immune checkpoint-like molecules of the B7 family. For this reason VSIG4 is a useful target for researchers studying complement biology, phagocytosis and the control of T-cell activation.
VSIG4 binds C3b and iC3b and inhibits the alternative complement pathway convertases, making it a focus for studies of complement regulation.
VSIG4 is a strong negative regulator of T-cell proliferation and IL2 production, relevant to work on immune suppression.
As a phagocytic receptor for complement-opsonised targets, VSIG4 is relevant to research on how innate cells recognise and clear particles.
VSIG4 is structurally related to the B7 family of immune regulatory proteins, so it is studied alongside other negative regulators of immune responses.
VSIG4 is a phagocytic receptor and a strong negative regulator of T-cell proliferation and IL2 production. It is also a receptor for the complement fragments C3b and iC3b and a potent inhibitor of the alternative complement pathway convertases.
VSIG4 is also called CRIg and Z39IG, and its full name is V-set and immunoglobulin domain containing 4. NCBI Gene reports that alternate splicing produces multiple transcript variants. Check the datasheet of any product for its validated reactivity and isoform coverage.
VSIG4 is structurally related to the B7 family of immune regulatory proteins and may negatively regulate T-cell responses. HGNC classes it among V-set domain containing proteins and among complement system regulators and receptors.
Other V-set and immunoglobulin domain containing proteins with products at Assay Genie.
Gene and protein annotations from HGNC, NCBI Gene and UniProt Q9Y279; product specifications from Assay Genie datasheets.