IL20RB is found in many organ resident effector cells such as keratinocytes at the skin epidermis, osteoclasts, found in bones, and epithelial cells of the intestine and trachea. IL20RB is also found in some immune cells.[7] The subunit has been linked with multiple diseases, including gastrointestinal diseases and glaucoma.
Structure and function
IL20RB is a β-chain with a short intracellulardomain. IL20RB, along with the IL-20 receptor, alpha subunit, form the heterodimeric type I interleukin-20 receptor, which binds the cytokinesIL-19, IL-20 and IL-24. IL20RB also associates with IL-22 receptor, to form the heterodimeric type II interleukin-20 receptor, which also binds IL-20 and IL-24.[6]
Signaling
After a cytokine binds both the IL20RB and the alpha subunit of the IL20 receptor, a signal is sent through the JAK-STAT signaling pathway. This signaling pathway leads STAT to act as a transcription factor, which can gene expression.[6]
IL20RB mRNA is expressed in retinal ganglion cells and optic nerves in rats. Mutations in the IL20RB gene are associated with glaucoma. The specific links between IL20RB and glaucoma are unknown, but IL20RB does not have a causative effect on the disease, instead contributing to an increased risk of the disease along with other factors, such as intraocular pressure.[5][8]
Pletnev S, Magracheva E, Kozlov S, Tobin G, Kotenko SV, Wlodawer A, Zdanov A (November 2003). "Characterization of the recombinant extracellular domains of human interleukin-20 receptors and their complexes with interleukin-19 and interleukin-20". Biochemistry. 42 (43): 12617–12624. doi:10.1021/bi0354583. PMID14580208.