|CD27||TNFRSF7 (tumor necrosis factor receptor superfamily, member 7), S152, T14, Tp55|
|Molecule Type||Antigen Expression||Molecular Weight|
Min / Max
|Lineage Restricted Molecule|
Type 1 glycoprotein
|55 / 55|
110 / 110
120 / 120
|CD27 is expressed on hemopoetic stem cells, a majority of peripheral blood T cells, early progenitor cells, preferentially on CD45RA+ T cells after activation, medullary thymocytes and on activated and memory-type B cells. B-cells acquire CD27 expression in the germinal center and keep on expressing the molecule until the plasma cell stage. CD27 is also expressed on NK cells.|
|MOLECULAR FAMILY NAME: Belongs to the tumor necrosis factor receptor superfamily.|
CD27 is a single-pass type-1 disulfide-linked homodimeric 240 aa glycoprotein. It contains an 171 aa extracellular domain which contains 2 cysteine-rich domains, a membrane-proximal half-TNF receptor domain and a N- and 3 O-glycosylation sites, a 21 aa transmembrane domain and a 48 aa C-terminal cytoplasmic domain containing a serine phosphorylation site but does not contain any known signaling motif. PIQEDYR motif in the cytoplasmic domain is essential for binding of TNF receptor associated fators TRAF2 and TRAF5.
CD27 cDNA does not contain a downstream poly A tract, causing the size difference between the cDNA of 1.2 kb and the mRNA of 1.3 kb.
CD27 has 1 N-linked and 3 O-linked glycosylation sites in the extracellular domain. Soluble CD27 is produced by lymphocytes upon activation, probably due to proteolytic cleavage. CD27 undergoes serine-phosphorylation in the intracellular cytoplasmic domain.
| LIGANDS AND MOLECULES ASSOCIATED WITH CD27 |
|CD27 is a T cell associated molecule and is important to B cells because it is a ligand for CD70 and is highly expressed on memory B cells. Ligating CD27 with CD70 drives memory B cells to become plasma cells. CD27 mediates a co-stimulatory signal for T and B cell activation and is involved in murine T cell development. Cells expressing CD70 can interact via CD27 to co-stimulate T cell proliferation, regulates differentiation of effector cells, generates cytotoxic T cells and enhance cytokine production. CD70 binding to CD27 on B cells, co-stimulates B cell proliferation and immunoglobulin production. Triggering on murine hematopoietic stem cells and early progenitors by CD70 inhibits differentiation to leukocytes. Knockout mice have normal overall hematopoiesis but have increased numbers of leukocytes, particularily B cells, and display impaired T cell responses after antigenic challenge. CD27 is involved in activation of NF-κB and stress-activated protein kinase (SAPK)/cJun N-terminal kinase (JNK). |
CD27 is phosphorylated on serine residues and hyperphosphorylated with T cell activation. Tyrosine-phosphorylation of ZAP-70 following CD27 ligation of T cells has been reported, but not confirmed independently.
DISEASE RELEVANCE AND FUNCTION OF CD27 IN INTACT ANIMAL
Levels of soluble CD27 in biological fluids increase in patients suffering from a variety of immunopathological diseases as a marker for T cell activation in vivo.
|MOLECULAR INTERACTIONS -|
PROTEINS AND DNA ELEMENTS WHICH REGULATE TRANSCRIPTION OF CD27
SUBSTRATES: No information.
ENZYMES WHICH MODIFY CD27: No information.
CD27/CD70 interactions regulate B cell proliferation and differentiation by T cells, in addition to T cell activation.
Database accession numbers
Revised June 25, 2008