CD45
CD45 (protein tyrosine phosphatase receptor type C, encoded by PTPRC) is a receptor-type protein tyrosine phosphatase that regulates antigen receptor and cytokine receptor signalling. It is also known as LCA, T200, GP180, LY5, B220 and CD45R. Browse Assay Genie's current range of CD45 research reagents below, or read on for the biology behind the target.
CD45 is a member of the protein tyrosine phosphatase (PTP) family, a group of signalling molecules that regulate cell growth, differentiation, mitosis and oncogenic transformation. It is an essential regulator of T- and B-cell antigen receptor signalling. It acts either through direct interaction with components of the antigen receptor complexes or by activating Src family kinases that the antigen receptor signalling pathway requires. CD45 also suppresses JAK kinases, so it works as a regulator of cytokine receptor signalling as well.
The CD45 protein is a receptor-type PTP. It has an extracellular domain, a single transmembrane segment and two tandem intracytoplasmic catalytic domains. It belongs to the protein-tyrosine phosphatase family, receptor class 1/6 subfamily, and is listed by HGNC within the CD molecules, fibronectin type III domain containing and receptor-type protein tyrosine phosphatase gene groups. UniProt places it at the cell membrane, in membrane rafts and at the synapse. The CD45 gene (PTPRC) has mouse and rat orthologs, both named Ptprc, and alternatively spliced transcript variants encoding distinct isoforms have been reported.
CD45 also has a role in microbial infection. It acts as a receptor for the human cytomegalovirus protein UL11 and mediates binding of UL11 to T-cells. This reduces the induction of tyrosine phosphorylation of multiple signalling proteins after T-cell receptor stimulation and impairs T-cell proliferation. The many names for the protein, including leukocyte common antigen (LCA), T200, GP180, LY5, B220 and CD45R, reflect its study across several systems.
CD45 is an essential regulator of T-cell antigen receptor signalling, acting through the receptor complex or through Src family kinases.
CD45 regulates B-cell antigen receptor signalling, making it a central target for studying how phosphatase activity shapes B-cell responses.
CD45 suppresses JAK kinases and so regulates cytokine receptor signalling, linking tyrosine dephosphorylation to cytokine responses.
CD45 is a receptor for human cytomegalovirus UL11, which reduces T-cell receptor signalling and impairs T-cell proliferation.
CD45 is a receptor-type protein tyrosine phosphatase and an essential regulator of T- and B-cell antigen receptor signalling. It interacts with antigen receptor components or activates Src family kinases, and it suppresses JAK kinases to regulate cytokine receptor signalling.
The CD45 gene symbol is PTPRC. Aliases include LCA, T200, GP180, LY5, B220 and CD45R. The official name is protein tyrosine phosphatase receptor type C. Alternatively spliced transcript variants encoding distinct isoforms have been reported.
Mouse and rat both have a Ptprc ortholog. In human infection, CD45 acts as a receptor for cytomegalovirus protein UL11, which binds T-cells and reduces T-cell receptor signalling and proliferation. Check the datasheet of any product for its validated reactivity.
Other receptor-type phosphatases, Src and Janus kinases, and immune cell markers involved in antigen receptor and cytokine signalling.
Gene and protein annotations from HGNC, NCBI Gene and UniProt P08575; product specifications from Assay Genie datasheets.