Functions as a membrane-bound signal-transducing subunit of the IL31 receptor complex (heterodimer composed of OSMR and IL31RA) which binds IL31 (PubMed:15184896, PubMed:15194700, PubMed:15627637). Functionally, IL31 signaling via OSMR/IL31RA is particularly important in skin immunity (PubMed:15184896). Mechanistically, ligand binding induces heterodimerization with OSMR, activating JAK1 and JAK2 (and to a lesser extent TYK2) associated with the intracellular domains of IL31RA and OSMR (PubMed:15194700, PubMed:15627637). These kinases phosphorylate tyrosine residues on IL31RA and OSMR, creating docking sites for STAT1, STAT3, and STAT5B, which are then phosphorylated and activated (Probable) (PubMed:11877449, PubMed:15194700, PubMed:15627637). In addition, the IL31 receptor complex activates the MAPK pathway (MAPK3/ERK1-MAPK1/ERK2) via recruitment of the adapter protein SHC1 (PubMed:15194700, PubMed:15627637). Mediates IL31-induced itch, probably in a manner dependent on cation channels TRPA1 and TRPV1 (By similarity). Positively regulates numbers and cycling status of immature subsets of myeloid progenitor cells in bone marrow in vivo and enhances myeloid progenitor cell survival in vitro (By similarity). {ECO:0000250|UniProtKB:Q8K5B1, ECO:0000269|PubMed:11877449, ECO:0000269|PubMed:15184896, ECO:0000269|PubMed:15194700, ECO:0000269|PubMed:15627637, ECO:0000305|PubMed:14504285}. This is the function of ENSG00000164509 (IL31RA, interleukin 31 receptor A).