Interleukin-7 receptor-α

Interleukin-7 receptor-α (IL-7Rα), also known as CD127 (cluster of differentiation 127), is a protein that in humans is encoded by the IL7R gene. It is a type I cytokine receptor, specifically binding interleukin-7 (IL-7) and is expressed on various cell types, including T cells, B cells, and dendritic cells.

Structure

IL-7Rα is a single-pass type I membrane protein, which means it crosses the cell membrane once and has its N-terminus on the outside of the cell. It is composed of an extracellular domain, a transmembrane domain, and an intracellular domain. The extracellular domain is responsible for binding to IL-7, while the intracellular domain is responsible for signal transduction.

Function

IL-7Rα, in combination with the common gamma chain (CD132), forms the high-affinity IL-7 receptor. This receptor plays a crucial role in the development and homeostasis of T cells and B cells. It is involved in the activation of JAK-STAT and PI3K-Akt pathways, leading to cell survival, proliferation, and differentiation.

Clinical significance

Mutations in the IL7R gene are associated with severe combined immunodeficiency (SCID), a rare genetic disorder characterized by the disturbed development of functional T cells and B cells. Moreover, the overexpression of IL-7Rα has been implicated in various types of cancers, including leukemia and lymphoma.

See also

• Interleukin-7
• Cytokine receptor
• Severe combined immunodeficiency