Common beta Chain: Proteins and Enzymes

The high-affinity receptors for Interleukin-3 (IL-3), IL-5, and Granulocyte-Macrophage Colony-stimulating Factor (GM-CSF) consist of a cytokine-specific a chain, and a shared common beta chain subunit (CD131) that is essential for receptor signaling. CD131 also associates with the receptor for Erythropoietin, forming a tissue-protective heteroreceptor complex. Phosphorylation of CD131 following receptor activation imparts growth and survival signals to the responding hematopoietic cells.