The lnterleukin-5/receptor interaction activates lyn and jak2 tyrosine kinases and propagates signals via the ras-raf-1-map kinase and the jak-stat pathways in eosinophils

Rafeul Alam, Konrad Pazdrak, Susan Stafford, Patricia Forsythe

    Research output: Contribution to journalArticle

    36 Scopus citations


    We have shown that the interaction of interleukin (IL)-5 with the receptor activates Lyn tyrosine kinase within 1 min and Jak2 tyrosine kinase within 1-3 min. IL-5 also stimulates GTP binding to p21'"'. The signal is subsequently propagated through the activation of Raf-1, MEK, and MAP kinases as shown by their increased autophosphorylation in vitro and phosphorylation in situ. Jak2 kinase has been shown to phosphorylate STAT nuclear proteins. The activation of STAT nuclear factors was studied by electrophoretic mobility shift assay using a y activation site (GAS) probe. We found that IL-5 induces two GAS-binding proteins in eosinophils, one of which is STAT1. We conclude that IL-5 induced signals are propagated through two distinct pathways: (1) Lyn→Ras→Raf-l-MEK→MAP kinase and (2) Jak2→STAT1.

    Original languageEnglish (US)
    Pages (from-to)226-227
    Number of pages2
    JournalInternational Archives of Allergy and Immunology
    Issue number1-3
    StatePublished - Jan 1 1995



    • Eosinophils
    • Interleukin-5
    • Kinase
    • Nuclear factor
    • Signal transduction

    ASJC Scopus subject areas

    • Immunology and Allergy
    • Immunology

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