New insights into the transmembrane protein tyrosine phosphatase CD45.
CD45 is expressed on all nucleated haematopoietic cells and was originally identified as the first and prototypic transmembrane protein tyrosine phosphatase. In CD45 mutant cell lines, CD45-deficient mice and CD45-deficient human SCID patients, CD45 is required for signal transduction through antigen receptors. CD45 can operate as a positive as well as a negative regulator of Src-family kinases. Moreover, CD45 was identified as the elusive JAK tyrosine phosphatase that negatively regulates cytokine receptor activation involved in the differentiation, proliferation and antiviral immunity of haematopoietic cells. Modulation of CD45 splice variants provides a unique opportunity to design drugs that turn off or turn on antigen and cytokine receptor signaling in cancer, transplantation or autoimmunity
Sasaki
T
T
Department of Pharmacology, Tokyo Metropolitan Institute of Medical Science, 3-18-22 Honkomagome, Bunkyo-ku, 113-8613, Tokyo, Japan. tsasaki@rinshoken.or.jp
Sasaki-Irie
J
J
Penninger
J M
JM
D000818:Animals; D004789:Enzyme Activation; D006801:Humans; D017493:Leukocyte Common Antigens / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D019860:Lymphocyte Specific Protein Tyrosine Kinase p56(lck) / Q000378:metabolism; D011505:Protein-Tyrosine Kinases / Q000378:metabolism; D015398:Signal Transduction
D011505:Protein-Tyrosine Kinases; D019860:Lymphocyte Specific Protein Tyrosine Kinase p56(lck); D017493:Leukocyte Common Antigens