IL-33 Proteins

Protein Information

IL-33 (Interleukin-33) is a 270 amino acid, highly divergent protein belonging to the IL-1 family with an IL-1-like C-terminal domain. IL-33 is a dual function protein that may function both as a proinflammatory cytokine and an intracellular nuclear factor with transcriptional regulatory properties. IL-33 binds to and signals through IL1RL1/ST2 and its stimulation recruits MYD88, IRAK1, IRAK4, and TRAF6. IL-33 activates NF-kappaB and MAP kinases, and drives production of TH2-associated cytokines from in vitro polarized TH2 cells. In vivo, IL-33 induces the expression of IL-4, IL-5, and IL-13 and leads to severe pathological changes in mucosal organs. IL-33 is proteolytically converted to a mature form by CASP1 and is highly expressed in high endothelial venules found in tonsils, Peyer's patches and mesenteric lymph nodes and is almost undetectable in placenta. Prolonged IL-33 treatment of mice led to the development of eosinophilia, splenomegaly, and severe pathological changes in mucosal organs such as lungs, esophagus and small intestine. Recent experiments have shown that IL-33 can also co-localize with heterochromatin and possesses transcriptional repressor activities, indicating that IL-33 may function as both a proinflammatory cytokine and an intracellular nuclear factor with transcriptional regulatory properties. Despite its predicted molecular weight, IL-33 will often run at higher molecular weight in SDS-PAGE. Studies have shown that IL-33 can also co-localize with heterochromatin and possesses transcriptional repressor activities, indicating that IL-33 may function as both a proinflammatory cytokine, and an intracellular nuclear factor with transcriptional regulatory properties.

Synonyms

9230117N10Rik; C9orf26; DVS27; DVS27-related protein; H-IL-33; IL1F11; IL-1F11; Il33; IL-33; ILN; Interleukin; interleukin 33; interleukin-1 family member 11; Interleukin33; Interleukin-33; Interleukin-33 (109-270); Interleukin-33 (95-270); Interleukin-33 (99-270); Interleukin-33(102-266); Interleukin-33(109-266); NFEHEV; NFHEV; NF-HEV; nuclear factor for high endothelial venules; nuclear factor from high endothelial venules; RGD1311155; RP11-575C20.2