Cell type-specific tyrosine phosphorylation of IL-2 receptor beta chain in response to IL-2.
Functional activities of the IL-2 receptor (IL-2R) beta chain exogenously expressed on lymphoid and non-lymphoid cells were examined in terms of phosphorylation of IL-2R beta and cell growth. Lymphoid MOLT-4 and its transfectants expressing IL-2R beta either alone or with IL-2R alpha chain were found to be rapidly phosphorylated predominantly at tyrosine residues of IL-2R beta and to be affected in their growth in an IL-2-dependent manner. In contrast, IL-2 induced neither phosphorylation of IL-2R beta nor cell growth in non-lymphoid transfectants derived from COS7, HeLa and L929, even though they acquired the IL-2 binding ability when coexpressed as IL-2R beta and IL-2R alpha. These results suggest that IL-2 induces activation of a tyrosine kinase possibly associated with IL-2R beta in a cell type-specific manner.
Kumaki
S
S
Department of Microbiology, Tohoku University, School of Medicine, Sendai, Japan.
Asao
H
H
Takeshita
T
T
Kurahayashi
Y
Y
Nakamura
M
M
Beckers
T
T
Engels
J W
JW
Sugamura
K
K
D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D015180:Electrophoresis, Gel, Two-Dimensional; D006801:Humans; D007376:Interleukin-2 / Q000378:metabolism* / Q000494:pharmacology; D010766:Phosphorylation; D011233:Precipitin Tests; D015375:Receptors, Interleukin-2 / Q000378:metabolism*; D013936:Thymidine / Q000378:metabolism; D014162:Transfection; D014407:Tumor Cells, Cultured; D014443:Tyrosine / Q000378:metabolism*
D007376:Interleukin-2; D015375:Receptors, Interleukin-2; D014443:Tyrosine; D013936:Thymidine