Gene transfer of the interleukin (IL)-2 receptor beta chain into an IL-7-dependent pre-B cell line permits IL-2-driven proliferation: tyrosine phosphorylation of Shc is induced by IL-2 but not IL-7.
Expression of the interleukin (IL)-2 receptor beta chain in the IL-7-dependent pre-B cell line IxN/2B permitted growth in presence of either IL-2 or IL-7, allowing for a direct comparison of intracellular signaling events. Protein tyrosine phosphorylation was essential for IL-2 and IL-7-induced signal transduction since the tyrosine kinase inhibitor herbimycin A blocked proliferation in response to both factors. Western blot analysis of tyrosine-phosphorylated proteins revealed that both IL-2 and IL-7 stimulation led to enhanced phosphorylation of proteins of 170-, 145-, 115- and 99-kDa, as well as induction of phosphorylation of a 96-kDa protein. However, a 55- and a 155-kDa protein were only phosphorylated after IL-2 stimulation. The 55-kDa protein specifically phosphorylated by IL-2 could be identified as p52shc which has recently been shown to be critically involved in Ras activation. Shc tyrosine phosphorylation as a result of IL-2 stimulation was consistently found in CTLL-2 cells and human T lymphoblasts. Taken together our results indicate that the IL-2- and IL-7-stimulated intracellular pathways are partially different and that Shc is a target of IL-2-, but not IL-7-, stimulated tyrosine phosphorylation.
Dorsch
M
M
Institut für Immunologie, Universitätsklinikum Steglitz, Freie Universität Berlin.
Hock
H
H
Diamantstein
T
T
D048868:Adaptor Proteins, Signal Transducing; D033942:Adaptor Proteins, Vesicular Transport; D000818:Animals; D016175:B-Lymphocyte Subsets / Q000166:cytology / Q000276:immunology*; D001483:Base Sequence; D016227:Benzoquinones; D015153:Blotting, Western; D002460:Cell Line; D007376:Interleukin-2 / Q000502:physiology*; D015851:Interleukin-7 / Q000502:physiology*; D047029:Lactams, Macrocyclic; D008213:Lymphocyte Activation; D051379:Mice; D008969:Molecular Sequence Data; D011233:Precipitin Tests; D011505:Protein-Tyrosine Kinases / Q000378:metabolism*; D011506:Proteins / Q000502:physiology; D011809:Quinones / Q000494:pharmacology; D015375:Receptors, Interleukin-2 / Q000235:genetics / Q000502:physiology*; D012190:Retroviridae / Q000502:physiology; D017828:Rifabutin / Q000031:analogs & derivatives; D055765:Shc Signaling Adaptor Proteins; D015398:Signal Transduction / Q000276:immunology*; D000071425:Src Homology 2 Domain-Containing, Transforming Protein 1; D014162:Transfection
D048868:Adaptor Proteins, Signal Transducing; D033942:Adaptor Proteins, Vesicular Transport; D016227:Benzoquinones; D007376:Interleukin-2; D015851:Interleukin-7; D047029:Lactams, Macrocyclic; D011506:Proteins; D011809:Quinones; D015375:Receptors, Interleukin-2; C528024:SHC1 protein, human; D055765:Shc Signaling Adaptor Proteins; C528034:Shc1 protein, mouse; D000071425:Src Homology 2 Domain-Containing, Transforming Protein 1; D017828:Rifabutin; C020754:herbimycin; D011505:Protein-Tyrosine Kinases