Granulocyte-Macrophage Colony-Stimulating Factor Receptor Alpha Chain (GM-CSF-Rα)

Granulocyte-macrophage colony-stimulating factor receptor alpha chain (GM-CSF-Rα), also known as CD116, is a key component of the heterodimeric receptor complex for granulocyte-macrophage colony-stimulating factor (GM-CSF). This receptor mediates the effects of GM-CSF, a cytokine critical for hematopoiesis and immune regulation. The GM-CSF receptor is composed of two subunits: Alpha chain (GM-CSF-Rα/CD116) which confers specific, low-affinity binding to GM-CSF, and Beta common chain (βc/gp140) which does not bind ligand alone but forms a high-affinity complex with α; it is shared with IL-3 and IL-5 receptors and is responsible for signal transduction. The α chain has an extracellular Ig-like domain essential for ligand binding. Expression is primarily on myeloid lineage cells, CD34+ hematopoietic progenitors, and some nonhematopoietic cells. It induces proliferation in early hematopoietic progenitors, stimulates differentiation along various myeloid lineages, and regulates mature cell function. It is an essential regulator at multiple stages of hematopoiesis and has clinical implications in hematopoietic progenitor mobilization, immune stimulation, and cancer therapy. Dysregulation can lead to chronic inflammation or malignancy. Upon ligand binding, dimerization with βc occurs, JAK2 associates with βc, initiating phosphorylation events leading to STAT5 activation, and STAT5 dimers translocate to the nucleus to drive gene transcription.

Other names

CD116

Agonist; Receptor dimerization and activation leading to downstream signaling (JAK2/STAT5, PI3K-Akt, ERK/NFkB)