O H 3 C H 3 C CH 3 OH CH 3 CH 3 O CH 3 OH CH 3 CH 3 O O

Leptomycin B

Article number:


CAS No.:





Elactocin; Mantuamycin; Antibiotic CI 940; Antibiotic CL 1957A

Molecular weight:

540,73 g/mol

Leptomycin B is an important tool in the study of nuclear export. Leptomycin B is twice as potent as Leptomycin A. Leptomycin B was originally discovered as a potent anti-fungal antibiotic from Streptomyces sp. However, recent data (2003) showed that Leptomycin causes G1 cell cycle arrest in mammalian cells and is a potent anti-tumor agent against murine experimental tumors. 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-?B/I?B, 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.

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Leptomycin B


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