Interleukin 11 receptor alpha subunit

Interleukin 11 receptor alpha subunit (IL11RA) is a protein that in humans is encoded by the IL11RA gene. This protein is a member of the interleukin 11 receptor family, a group of cytokine receptors known for mediating the biological effects of interleukin 11 (IL11), a cytokine involved in several processes such as hematopoiesis, inflammation, and bone homeostasis. IL11RA specifically binds to IL11, forming a complex with gp130 (also known as IL6ST), a signal-transducing receptor component shared by various cytokines, to initiate signaling pathways that are crucial for the aforementioned biological processes.

Structure

IL11RA is a transmembrane protein that consists of an extracellular domain responsible for binding IL11, a single transmembrane domain, and a short cytoplasmic tail. The extracellular domain contains several conserved cysteine residues and a WSXWS motif, characteristic of the cytokine receptor family, which is essential for proper folding and function of the receptor.

Function

Upon binding to IL11, IL11RA associates with gp130, leading to the dimerization of gp130 molecules. This dimerization triggers the activation of intracellular signaling cascades, including the JAK-STAT signaling pathway, the MAPK signaling pathway, and the PI3K-Akt signaling pathway. These pathways play significant roles in cell survival, proliferation, differentiation, and apoptosis. The IL11-IL11RA interaction is particularly important in the regulation of megakaryocyte maturation and platelet production, osteoclastogenesis, and the protective mechanisms of the gastrointestinal tract.

Clinical Significance

Mutations in the IL11RA gene have been associated with various diseases. For instance, abnormalities in IL11 signaling can lead to disorders of bone formation and remodeling, such as osteoporosis and Paget's disease of bone. Additionally, due to its role in inflammation and immune response modulation, IL11RA has been implicated in inflammatory diseases, including rheumatoid arthritis and inflammatory bowel disease (IBD).

Given its involvement in critical biological processes and disease pathogenesis, IL11RA and its ligand, IL11, are considered potential therapeutic targets. Drugs that modulate the IL11-IL11RA interaction could be beneficial in treating conditions related to bone health, hematopoiesis, and chronic inflammation.

Genetics

The IL11RA gene is located on chromosome 9 in humans. It consists of several exons that encode the different domains of the IL11RA protein. Genetic studies have identified polymorphisms within the IL11RA gene that may influence the risk of developing certain diseases or affect the response to treatments that target the IL11-IL11RA pathway.

See Also

• Interleukin 11
• Cytokine receptor
• JAK-STAT signaling pathway
• MAPK signaling pathway
• PI3K-Akt signaling pathway