来普霉素 B 是一种抗真菌抗生素、抗肿瘤细胞毒素,可抑制CRM1 依赖、NES 依赖的核质转运(核输出抑制剂)。含 NES(核输出信号)的蛋白包括 HIV-1 REV、肌动蛋白、c-Abl、周期蛋白 B1、MDM2/p53、IκB、MPF、PKA 以及 MEK。
来普霉素 B 是强效、特异性的核输出抑制剂。它可烷基化并抑制 CRM1(染色体区域维持蛋白 1,又称输出蛋白 1);该蛋白是携带核输出序列(NES)的蛋白实现核输出所必需的蛋白。
除抗真菌、抗菌活性外,来普霉素 B 能够阻滞细胞周期,是一种强效抗肿瘤试剂。在纳摩尔级低浓度下,来普霉素 B 可阻断多种蛋白的核输出,包括 HIV-1 Rev、MAPK/ERK、NF-κB/IκB,并稳定 p53 的表达。来普霉素 B 还可通过抑制核糖核蛋白的出核,阻断包括 COX-2、c-Fos mRNA 在内的多种 RNA 的输出与翻译。
Leptomycin B is an anti-fungal antibiotic, anti-tumor cytotoxin that inhibits CRM1-dependent, NES-dependent nucleo-cytoplasmic translocation (nuclear export inhibitor). NES containing proteins include HIV-1 REV; actin, c-Abl, cyclin B1, MDM2/p53, IB, MPF, PKA and MEK. Leptomycin B is a potent and specific nuclear export inhibitor. Leptomycin B alkylates and inhibits CRM1 (chromosomal region maintenance)/exportin 1, a protein required for nuclear export of proteins containing a nuclear export sequence (NES). In addition to antifungal and antibacterial activities, Leptomycin B blocks the cell cycle and is a potent anti-tumor agent. At low nM concentrations, Leptomycin B blocks the nuclear export of many proteins including HIV-1 Rev, MAPK/ERK, and NF-κB/IκB, and it stabilizes the expression of p53. Leptomycin B also inhibits the export and translation of many RNAs, including COX-2 and c-Fos mRNAs, by inhibiting export of ribonucleoproteins.