Abstract
One of the earliest events induced by interleukin 2 (IL-2) is tyrosine phosphorylation of cellular proteins, including the IL-2 receptor beta chain (IL-2Rbeta). Simultaneous mutation of three tyrosines (Y338, Y392, and Y510) in the IL-2Rbeta cytoplasmic domain abrogated IL-2-induced proliferation, whereas mutation of only Y338 or of Y392 and Y510 inhibited proliferation only partially. While Y392 and Y510 were critical for IL-2-induced activation of signal transducers and activators of transcription (STAT proteins), Y338 was required for Shc-IL-2Rbeta association and for IL-2-induced tyrosine phosphorylation of Shc. Thus, activation of both Jak-STAT and Shc-coupled signaling pathways requires specific IL-2Rbeta tyrosines that together act in concert to mediate maximal proliferation. In COS-7 cells, overexpression of Jak1 augmented phosphorylation of Y338 as well as Y392 and Y510, suggesting that the role for this Jak kinase may extend beyond the Jak-STAT pathway.
Publication types
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Research Support, Non-U.S. Gov't
MeSH terms
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Adaptor Proteins, Signal Transducing*
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Adaptor Proteins, Vesicular Transport*
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Amino Acid Sequence
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Animals
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Base Sequence
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Cells, Cultured
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Chlorocebus aethiops
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DNA-Binding Proteins / metabolism
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Humans
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Janus Kinase 1
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Lymphocyte Activation*
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Mice
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Molecular Sequence Data
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Mutagenesis, Site-Directed
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Phosphotyrosine / chemistry
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Protein Binding
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Protein-Tyrosine Kinases / metabolism
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Proteins / metabolism
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Receptor Aggregation
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Receptors, Interleukin-2 / chemistry
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Receptors, Interleukin-2 / physiology*
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STAT1 Transcription Factor
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Shc Signaling Adaptor Proteins
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Signal Transduction*
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Src Homology 2 Domain-Containing, Transforming Protein 1
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T-Lymphocytes / physiology*
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Trans-Activators / metabolism
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Tyrosine / chemistry
Substances
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Adaptor Proteins, Signal Transducing
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Adaptor Proteins, Vesicular Transport
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DNA-Binding Proteins
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Proteins
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Receptors, Interleukin-2
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SHC1 protein, human
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STAT1 Transcription Factor
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STAT1 protein, human
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Shc Signaling Adaptor Proteins
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Shc1 protein, mouse
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Src Homology 2 Domain-Containing, Transforming Protein 1
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Stat1 protein, mouse
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Trans-Activators
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Phosphotyrosine
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Tyrosine
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Protein-Tyrosine Kinases
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JAK1 protein, human
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Jak1 protein, mouse
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Janus Kinase 1