1. Association of RACK1 and PKCβ with the common β-chain of the IL-5/IL-3/GM-CSF receptor.
- Author
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Geijsen, Niels, Spaargaren, Marcel, Raaijmakers, Jan AM, Lammers, Jan-Willem J, Koenderman, Leo, and Coffer, Paul J
- Subjects
CYTOKINES ,INTERLEUKINS - Abstract
Granulocyte macrophage colony stimulating factor (GM-CSF), interleukin-3 (IL-3) and interleukin-5 (IL-5 belong to a family of cytokines that regulate proliferation, differentiation and function of haematopoietic cells. Their receptor consists of a ligand specific α-chain and a signal transducing β-chain (βc). While, the role of phosphotyrosine residues in the βc as mediators of downstream signalling cascades has been established, little is known about non-phosphotyrosine mediated events. To identify proteins interacting with βc, we screened a yeast two-hybrid library with the intracellular domain of βc. We found that RACK1, a molecule associating with activated PKC, PLCγ and Src kinases, associated with the membrane proximal region of βc in both yeast two-hybrid, immunoprecipitation and GST-pull-down assays. The association of RACK1 was constitutive, demonstrating no alteration upon cellular stimulation. Furthermore, upon stimulation of cells with IL-5 or PMA, a complex of βc and PKCβ was found. Together, these findings suggest a novel role for RACK1 as a possible adapter molecule associating with the intracellular domain of cytokine receptors. [ABSTRACT FROM AUTHOR]
- Published
- 1999
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