Importazole (662163-81-7) specifically inhibits importin-β-mediated nuclear import without disrupting transportin-mediated nuclear import or CRM1-mediated nuclear export.1 When added to cells during mitosis, importazole impairs the release of an importin-β cargo probe and causes defects in spindle assembly. Disrupts proteostasis and triggers infolded protein response-mediated apoptosis.5 Inhibition of importin-β function is most likely mediated by blocking its interaction with RanGTP. Importazole is an important new tool to probe the function of the importin-β/RanGTP pathway.2-4 Cell permeable.
1) Soderholm et al. (2011), Importazole, a small molecule inhibitor of the transport receptor importin-β; ACS Chem. Biol., 6 700
2) Bird et al. (2013), RanGTP and CLASP1 cooperate to position the mitotic spindle; Mol. Biol. Cell, 24 2506
3) Bai et al. (2014), Importin β-dependent nuclear import of TopBP1 in ATR-Chk1 checkpoint in Xenopus egg extracts; Cell Signal., 26 857
4) Yan et al. (2015), Importin β1 mediates nuclear factor-κB signal transduction into the nuclei of myeloma cells and affects their proliferation and apoptosis; Cell Signal., 27 851
5) Zhu et al. (2018), KPNB1 inhibition disrupts proteostasis and triggers unfolded protein response-mediated apoptosis in glioblastoma cells; Oncogene 37 2936