LY9
LY9 (lymphocyte antigen 9, also known as CD229 or SLAMF3) is a self-ligand cell-surface receptor of the signalling lymphocytic activation molecule (SLAM) family. It helps regulate the activation and differentiation of immune cells, and is also written mLY9 or hly9 in some sources. Browse Assay Genie's current range of LY9 research reagents below, or read on for the biology behind the target.
LY9 is a self-ligand receptor belonging to the SLAM family of immunomodulatory receptors. SLAM receptors are triggered by homotypic or heterotypic cell-cell interactions, and they modulate the activation and differentiation of a wide variety of immune cells. In this way they take part in regulating and linking the innate and adaptive immune responses. Their activity is controlled by the presence or absence of small cytoplasmic adapter proteins, SH2D1A (SAP) and/or SH2D1B (EAT-2). LY9 interacts with SAP, and it may take part in adhesion between T lymphocytes and accessory cells through homophilic interaction.
Functional studies summarised in UniProt place LY9 at the interface between T-cell activation and tolerance. It promotes T-cell differentiation towards a helper T-cell Th17 phenotype, leading to increased IL-17 secretion. This costimulatory activity requires SH2D1A, and LY9 promotes recruitment of RORC to the IL-17 promoter. LY9 may also act as a negative regulator of the immune response, helping to maintain peripheral tolerance. It may disable autoantibody responses and inhibit IFN-gamma secretion by CD4(+) T-cells, and it may negatively regulate the size of the thymic innate CD8(+) T-cell population and the development of invariant natural killer T (iNKT) cells.
The human LY9 gene encodes a membrane protein that localises to the cell membrane. HGNC classifies it among the CD molecules and the immunoglobulin-like domain containing genes. The protein is known as CD229 and SLAMF3, and its mouse counterpart is Ly9. Researchers studying the LY9 gene or the LY9 protein often examine it alongside other SLAM family receptors and their SAP-family adapters.
LY9 promotes helper T-cell differentiation towards a Th17 phenotype with increased IL-17 secretion, making it relevant to studies of effector T-cell programming.
LY9 may act as a negative regulator of the immune response and may disable autoantibody responses, so it is studied in peripheral tolerance.
LY9 signalling depends on adapters such as SH2D1A/SAP and SH2D1B/EAT-2, which makes it a model for adapter-controlled receptor function.
LY9 may negatively regulate thymic innate CD8(+) T-cell numbers and iNKT cell development, linking it to lymphocyte lineage research.
LY9 is a self-ligand SLAM family receptor that modulates immune cell activation and differentiation. It may mediate T-cell adhesion to accessory cells, promotes Th17 differentiation with IL-17 secretion, and may negatively regulate immune responses to support peripheral tolerance. Its signalling is controlled by SAP and EAT-2 adapters.
LY9 stands for lymphocyte antigen 9, and UniProt names the protein T-lymphocyte surface antigen Ly-9. Aliases include CD229, SLAMF3, mLY9 and hly9. The SLAMF3 name reflects its place in the SLAM family, and CD229 is its cluster of differentiation designation.
Yes, the mouse ortholog is Ly9. The human gene is annotated as a CD molecule and an immunoglobulin-like domain containing gene. No rat ortholog is given in the data used here, so check the datasheet of any product for its validated reactivity.
Other lymphocyte antigens, immune receptors and related immunology targets with products at Assay Genie.
Gene and protein annotations from HGNC, NCBI Gene and UniProt Q9HBG7; product specifications from Assay Genie datasheets.