4u8C

14003-96-4

C11H8O4

DMSO : >= 27 mg/mL (132.24 mM)

Cell Cycle/DNA Damage

4u8C (IRE1 Inhibitor III) is a small-molecule inhibitor of IRE1alpha. In Vitro: When applies to the media of ER stressed cultured cells, 4u8C inhibits Xbp1 splicing in a concentration-dependent manner. 4u8C dissociates slowly from IRE1, but ishout of inhibitor leads to rapid recovery of Xbp1 splicing in cells^[1].The IRE1 endoribonuclease inhibitor 4u8c prevents the splicing of the XBP1 mRNA in response to ER stress caused by mutant proinsulin production^[2]. The inositol-requiring enzyme 1alpha (IRE1alpha) is a serine-threonine kinase that plays crucial roles in activating the unfolded protein response. 4u8C treatment dramatically inhibits IL-4 production by CD4⁺ T cells under Th0 conditions because both the IL-4 levels in the culture supernatant and the percentage of IL-4 positive cells are reduced by 4u8C treatment. In addition, both IL-5 and IL-13 production are significantly reduced upon treatment with 4u8C^[3]. In Vivo: 4u8C reverses the ER stress-dependent loss of several known RIDD targets, with an EC₅₀ of approximately 4 uM, approximating that of inhibition of XBP1 target gene activation^[1].