IL-2-dependent in vivo and in vitro tyrosine phosphorylation of IL-2 receptor gamma chain.
We previously reported a molecule, p64, which was tentatively named the gamma chain, coprecipitable with the beta chain of human interleukin-2 receptor (IL-2R). The present study demonstrated that the gamma chain, as well as the beta chain expressed on IL-2-responsive cells, is phosphorylated on tyrosine residues in an IL-2-dependent manner in vivo and in vitro. The in vivo tyrosine phosphorylation of both chains was similarly induced within 1 min after IL-2 stimulation, and their in vitro tyrosine phosphorylation with the anti-IL-2R beta antibody-directed immunocomplex was also increased by treatment of cells with IL-2. These results suggest that a tyrosine kinase is associated with the beta gamma subunit complex, of which activation by IL-2 may result in transduction of intracellular signals.
Asao
H
H
Department of Microbiology, Tohoku University School of Medicine, Sendai, Japan.
Kumaki
S
S
Takeshita
T
T
Nakamura
M
M
Sugamura
K
K
D000595:Amino Acid Sequence; D002460:Cell Line; D004789:Enzyme Activation; D006801:Humans; D007376:Interleukin-2 / Q000494:pharmacology*; D008969:Molecular Sequence Data; D010766:Phosphorylation; D011505:Protein-Tyrosine Kinases / Q000378:metabolism*; D015375:Receptors, Interleukin-2 / Q000378:metabolism*; D013601:T-Lymphocytes
D007376:Interleukin-2; D015375:Receptors, Interleukin-2; D011505:Protein-Tyrosine Kinases