Cd5
Function
Lymphoid-specific receptor expressed by all T-cells and in a subset of B-cells known as B1a cells. Plays a role in the regulation of TCR and BCR signaling, thymocyte selection, T-cell effector differentiation and immune tolerance (PubMed:35720357). Acts by interacting with several ligands expressed on B-cells such as CD5L or CD72 and thereby plays an important role in contact-mediated, T-dependent B-cell activation and in the maintenance of regulatory T and B-cell homeostasis (PubMed:24950378, PubMed:9064341, PubMed:9723705). Functions as a negative regulator of TCR signaling during thymocyte development by associating with several signaling proteins including LCK, CD3Z chain, PI3K or CBL (PubMed:11157848). Mechanistically, co-engagement of CD3 with CD5 enhances phosphorylated CBL recruitment leading to increased VAV1 phosphorylation and degradation (By similarity). Modulates B-cell biology through ERK1/2 activation in a Ca(2+)-dependent pathway via the non-selective Ca(2+) channel TRPC1, leading to IL-10 production (By similarity).
Post-translational modifications
Phosphorylated on serine, threonine and tyrosine residues following TCR stimulation (PubMed:11007759). Phosphorylated by LCK on Tyr-452 and Tyr-486 upon TCR engagement (PubMed:11157848).
Cellular localization
- Cell membrane
- Single-pass type I membrane protein
Alternative names
CD5, Ly-1, Cd5, T-cell surface glycoprotein CD5, Lymphocyte antigen 1, Lyt-1