The function of Ensembl gene identifier ENSG00000110944 (IL23A, interleukin 23 subunit alpha) is as follows. Associates with IL12B to form the pro-inflammatory cytokine IL-23 that plays different roles in innate and adaptive immunity (PubMed:11114383). Released by antigen-presenting cells such as dendritic cells or macrophages, binds to a heterodimeric receptor complex composed of IL12RB1 and IL23R to activate JAK2 and TYK2 which then phosphorylate the receptor to form a docking site leading to the phosphorylation of STAT3 and STAT4 (PubMed:29287995, PubMed:32474165, PubMed:33606986). This process leads to activation of several pathways including p38 MAPK or NF-kappa-B and promotes the production of pro- inflammatory cytokines such as interleukin-17A/IL17A (PubMed:12023369). In turn, participates in the early and effective intracellular bacterial clearance (PubMed:32474165). Promotes the expansion and survival of T-helper 17 cells, a CD4-positive helper T-cell subset that produces IL-17, as well as other IL-17-producing cells (PubMed:17676044). {ECO:0000269|PubMed:11114383, ECO:0000269|PubMed:12023369, ECO:0000269|PubMed:16424222, ECO:0000269|PubMed:17676044, ECO:0000269|PubMed:29287995, ECO:0000269|PubMed:32474165, ECO:0000269|PubMed:33606986}.