ZAP-70: a 70 kd protein-tyrosine kinase that associates with the TCR zeta chain.
Protein-tyrosine kinases (PTKs) play an integral role in T cell activation. Stimulation of the T cell antigen receptor (TCR) results in tyrosine phosphorylation of a number of cellular substrates. One of these is the TCR zeta chain, which can mediate the transduction of extracellular stimuli into cellular effector functions. We have recently identified a 70 kd tyrosine phosphoprotein (ZAP-70) that associates with zeta and undergoes tyrosine phosphorylation following TCR stimulation. Here we report the isolation of a cDNA clone encoding ZAP-70. ZAP-70 represents a novel PTK and is expressed in T and natural killer cells. Moreover, tyrosine phosphorylation and association of ZAP-70 with zeta require the presence of src family PTKs and provide a potential mechanism by which the src family PTKs and ZAP-70 may interact to mediate TCR signal transduction.
Chan
A C
AC
Division of Rheumatology, University of California, San Francisco 94143.
Iwashima
M
M
Turck
C W
CW
Weiss
A
A
D000595:Amino Acid Sequence; D001483:Base Sequence; D015152:Blotting, Northern; D015153:Blotting, Western; D003001:Cloning, Molecular; D006801:Humans; D008565:Membrane Proteins / Q000378:metabolism*; D008969:Molecular Sequence Data; D010766:Phosphorylation; D011505:Protein-Tyrosine Kinases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D011948:Receptors, Antigen, T-Cell / Q000378:metabolism*; D015183:Restriction Mapping; D017386:Sequence Homology, Amino Acid; D015398:Signal Transduction / Q000502:physiology; D014407:Tumor Cells, Cultured; D014443:Tyrosine / Q000378:metabolism; D051746:ZAP-70 Protein-Tyrosine Kinase
D008565:Membrane Proteins; D011948:Receptors, Antigen, T-Cell; C054979:antigen T cell receptor, zeta chain; D014443:Tyrosine; D011505:Protein-Tyrosine Kinases; D051746:ZAP-70 Protein-Tyrosine Kinase; C497261:ZAP70 protein, human