The IL-4 Receptor — Signaling Mechanisms
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Interleukin-4 (IL-4) is a multifunctional cytokine that is a member of the hematopoietin family1. Its structure consists of a bundle of four left handed α helices in which the first and second and the third and fourth helices are connected by long over hand loops2,3,4,5. IL-4 is produced by CD4+ T cells1 and by basophils and mast cells6 in response to receptor-mediated stimulation. It mediates its functions by binding to high affinity receptors expressed on a wide range of hematopoeitic and non-hematopoietic cell types7. The molecule defined as the IL-4 receptor (IL-4R) possesses an extracellular domain that is a member of the hematopoeitin-receptor family8. Its cytosolic domain is ~500 amino acids in length and lacks both endogenous tyrosine kinase and nucleotide-binding motifs9. The IL-4R does possess two acid rich regions and sequences homologous to the Box 1 region defined for the gp130 component of the IL-6 receptor10.
KeywordsTyrosine Phosphorylation Cytosolic Domain Fourth Helix Receptor Gamma Chain Acid Rich Region
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- 2.R. Powers, D.S. Garrett, C.J. March, E.A. Frieden, A.M. Gronenborn, and G.M. Clore, The high-resolution, three-dimensional solution structure of human interleukin-4 determined by multidimensional heteronuclear magnetic resonance spectroscopy, Biochemistry. 32:6744 (1993).PubMedCrossRefGoogle Scholar
- 22.A.D. Keegan, K. Nelms, M.F. White, L.-M. Wang, J.H. Pierce, and W.E. Paul, A region of the interleukin-4 receptor containing a motif found in the insulin receptor is important for IL-4 mediated IRS-1 phosphorylation and proliferation, Cell. 76:in press (1994).Google Scholar