Alternative titles; symbols
HGNC Approved Gene Symbol: IL20RB
Cytogenetic location: 3q22.3 Genomic coordinates (GRCh38) : 3:136,957,983-137,011,085 (from NCBI)
IL20RB and IL20RA (605620) form a heterodimeric receptor for interleukin-20 (IL20; 605619) (Blumberg et al., 2001).
By RT-PCR of human tissues, Blumberg et al. (2001) detected highest expression of IL20RB in skin and testis, with lower levels in ovary, placenta, lung, muscle, and heart. Little to no expression was detected in other tissues examined.
Blumberg et al. (2001) identified the receptor for IL20 as a heterodimer of 2 orphan class II cytokine receptor subunits, IL20RA and IL20RB. Binding assays using radiolabeled ligand demonstrated that IL20 bound to BHK transfectants expressing both IL20RA and IL20RB, but not to untransfected cells nor to transfectants expressing either receptor subunit alone. Binding of (125)I-labeled IL20 was eliminated in the presence of 100-fold excess of unlabeled IL20, but not in the presence of 100-fold excess of the unrelated cytokine, IL21 (605384). The binding data revealed 88,000 IL20 receptors per cell, with a binding affinity of approximately 1.5 nM.
Using in situ hybridization, Blumberg et al. (2001) found dramatic upregulation of both IL20RA and IL20RB mRNA in keratinocytes of psoriatic skin compared with normal skin. In some psoriatic skin samples, expression of both IL20RA and IL20RB was observed in mononuclear immune cells and in endothelial cells in a subset of vessels.
By receptor binding analysis, Wang et al. (2002) showed that human IL24 (604136) interacted with both IL20RA/IL20RB and IL22RA (605457)/IL20RB heterodimers.
Blumberg, H., Conklin, D., Xu, W., Grossmann, A., Brender, T., Carollo, S., Eagan, M., Foster, D., Haldeman, B. A., Hammond, A., Haugen, H., Jelinek, L., and 14 others. Interleukin 20: discovery, receptor identification, and role in epidermal function. Cell 104: 9-19, 2001. [PubMed: 11163236] [Full Text: https://doi.org/10.1016/s0092-8674(01)00187-8]
Wang, M., Tan, Z., Zhang, R., Kotenko, S. V., Liang, P. Interleukin 24 (MDA-7/MOB-5) signals through two heterodimeric receptors, IL-22R1/IL-20R2 and IL-20R1/IL-20R2. J. Biol. Chem. 277: 7341-7347, 2002. [PubMed: 11706020] [Full Text: https://doi.org/10.1074/jbc.M106043200]