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LEPTOMYCIN A+B Inhibitors of Nuclear-Cytoplasmic Transport Highlighthighlight Tomorrow’S Reagents Manufactured Today™ International Version

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LEPTOMYCIN A+B Inhibitors of Nuclear-Cytoplasmic Transport Highlighthighlight Tomorrow’S Reagents Manufactured Today™ International Version PRODUCT FLYER LEPTOMYCIN A+B Inhibitors of Nuclear-Cytoplasmic Transport highlighthighlight Tomorrow’s Reagents Manufactured Today™ International Version Available Nuclear Transport at Best Prices! In eukaryotic cells, the enclosure of ge- 65nm long aqueous channel. Transport oc- netic information by the nucleus allows the curs by a variety of different pathways, de- spatial and temporal separation of DNA rep- fined by individual receptors and accessory Leptomycin A+B lication and transcription in the nucleus from soluble factors. Soluble factors selectively cytoplasmic protein synthesis. This compart- target substrates/cargo for import and ex- mentalization permits a high level of regula- port as well as deliver them to their appropri- Leptomycin A [LMA] tion of these processes, but at the same time ate intracellular destination. Macromolecules ALX-380-101-C050 50 µg necessitates a system of selective macromo- (cargo) transported through these channels ALX-380-101-C100 100 µg lecular transport between the nucleus and include proteins and RNA, as individual enti- An antifungal antibiotic that acts as an inhibitor cytoplasm [1, 2]. ties or as part of larger complexes such as the of nuclear export by interacting with CRM1/ex- The term nuclear-cytoplasmic transport ribosomal subunits. While small molecules portin-1. Inhibits nucleo-cytoplasmic transloca- such as ions and proteins of up to 60kDa tion of molecules such as the HIV-1 Rev protein refers to the movement of a large variety of and Rev-dependent export of mRNA. macromolecules both into and out of the can diffuse through the NPC, small proteins nucleus. actively cross the NPC in a carrier-mediated SOURCE: Isolated from Streptomyces sp. fashion [3, 4]. FORMULATION: In 100% ethanol. A single type of channel, the nuclear Proteins to be imported into the nucle- MW: 526.7. FORMULA: C H O pore complex (NPC), mediates all move- 32 46 6 ment across the nuclear envelope. The NPC us contain sequences termed nuclear locali- PURITY: ≥95% (HPLC). CAS: 87081-36-5 is a massive structure, completely spanning zation sequences (NLS), and proteins to be For Bulk Quantities please inquire! the two membranes that separate the nucle- exported from the nucleus contain nuclear export sequences (NES). These signals are re- Manufactured by Novartis AG for us from the cytoplasm and housing a central Dolder AG Switzerland Leptomycin B [LMB] ALX-380-100-C100 100 µg An antifungal antibiotic that acts as an inhibi- tor of nuclear export by interacting with CRM1/ exportin-1. Inhibits nucleo-cytoplasmic trans- location of molecules such as the HIV-1 Rev protein and Rev-dependent export of mRNA. Other proteins that are influenced by leptomy- cin B are actin, c-Abl, cyclin B1, MDM2/p53, Iκb, MPF and PKA. SOURCE: Isolated from Streptomyces sp. FORMULATION: In 100% ethanol. MW: 540.7. FORMULA: C33H48O6 PURITY: ≥95% (HPLC). CAS: 87081-35-4 For Bulk Quantities please inquire! Leptomycin Set I ALX-850-313-KI01 1 Set The Set contains 1 x 100µg each of Leptomycin A (Prod. No. ALX-380-101) and Leptomycin B (Prod. No. ALX-380-100). FIGURE 1: Classical nuclear-cytoplasmic transport 2 IMMUNOLOGYLEPTOMYCIN A+B cognized by soluble factors that work with the RanGTPase cycle to coordinate import or export Leptomycin B: A Well Established Standard from nucleus [5, 6]. Leptomycin B (LMB) is an antibiotic with of many proteins including HIV-1 Rev (the hu- Protein import process: The NLS is a protein anti-fungal and anti-tumor activity that was man immunodeficiency virus type 1 regula- motif containing a cluster of basic residues that first discovered and purified from the fermen- tory protein), MAPK/ERK, and NF-κB/IκB. Ad- is recognized by soluble adapter proteins known tation broth and mycelia of Streptomyces. LMB ditionally, it also stabilizes the expression of as importins. The importin proteins, also termed (C33H48O6) is an unsaturated, branched chain p53 by protecting p53 from Mdm2-mediated karyopherins (Table 1), is one member of a con- fatty acid with a terminal lactone ring (Figure degradation and inducing p53 transcriptional served family of transport receptors. Each mem- 3). activity. Leptomycin B also inhibits the export ber of this conserved family recognizes a distinct Later, this drug was shown to inhibit the G1 and translation of many RNAs, including COX- NLS. Through a cascade of associations with oth- 2 and c-Fos mRNAs, by inhibiting export of ri- er components within the nuclear translocation and G2 phases of the cell cycle, and other cel- lular functions. These pleotropic effects led to bonucleoproteins. Other proteins that have process, the importins ultimately interact with been shown to be influenced by leptomycin the phenylalanine-glycine (FG) repeat regions the study of the mechanisms by which lepto- mycin B influences intracellular processes. One B, include actin, c-Abl, cyclin B1, MPF, PKA and of the nucleoporins (a protein subunit of the nu- many others [20-29]. clear pore complex) and with the cofactor Ran- of these studies involved a screen of leptomy- GTP (the GTP-bound form of the RanGTPase) to cin B resistance genes in fission yeast. In this Export of mRNA and certain proteins from discharge the cargo in the nucleus. Alternatively, screen it was found that leptomycin B targets the nucleus is a key step in protein produc- an importin-independent pathway also exists. In CRM1 (exportin-1), a fission yeast nuclear pro- tion, proliferation, and apoptosis. Therefore, this case, the cargos contain several HEAT-like tein, which was thought to be involved in the this antibiotic has become an important tool repeats and can associate directly with the nu- control of gene expression [16-19]. for studying nuclear localization and traffick- cleo-porins [5-10]. Leptomycin B forms a covalent complex ing in eukaryotic cells. Mechanism for nuclear export: Studies of with the sulfhydryl group of a conserved the HIV Rev and the cellular PKI (protein kinase cysteine residue in CRM1, thereby inhibiting A inhibitor) proteins led to the discovery of the CRM1 interaction with the nuclear export sig- leucine-rich nuclear export signal (NES) and the nal (NES) of targeted export proteins. The abil- very well characterized CRM1/exportin-1 (chro- ity of leptomycin B to inhibit nuclear export has made it a useful tool in the study of the mosome region maintenance 1) pathway of nu- FIGURE 3 clear export. CRM1 is a karyopherin specific for subcellular localization of many regulatory pro- nuclear export (exportin 1). The CRM1 protein di- teins. Leptomycin B blocks the nuclear export rectly binds proteins that contain a leucine-rich NES. In addition, the export mechanism appears to involve CRM1 binding to both Ranγ-GTP and nucleoporins (Figure 1) [11-14]. Leptomycin A: The Unexplored Alternative! Nuclear-cytoplasmic transport is an impor- Leptomycin A (LMA) (Figure 2) is an antifun- to the lack of supply and high prices, LMA is tant aspect of normal cell function. Defects in gal antibiotic that inhibits nucleo-cytoplasmic still unexplored. this process have been detected in many differ- translocation of Rev and MAPK/ERK, by inhib- ent types of cancer cells. These defects can occur iting their export. LMA belongs to a defined in the signal transduction pathways that regulate panel of nuclear export inhibitors, including the transfer of factors such as p53 and β-catenin leptomycin and ratjadones. Although most in and out of the nucleus, or in the general nucle- of research done on leptomycin was done on us import and export machinery itself [15]. LMB, the specifications for LMA indicate simil- iar blocking potential of the nuclear export FIGURE 2 system by leptomycin A [16-18, 30, 31]. Due Literature References 1 Nucleocytoplasmic transport: taking an inventory: H. Fried and U. Kutay; Cell. Mol. Life Sci. 60, 1659 (2003) (Review) 2 Nuclear Func- tions for Plasma Membrane-Associated Proteins?: A. Benmerah, et al.; Traffic 4, 503 (2005) (Review) 3 The nuclear pore complex: a protein machine bridging the nucleus and cytoplasm: K.J. Ryan and S.R. Wente; Curr. Opin. Cell Biol. 12, 361 (2000) (Review) 4 Gatekeepers of the nucleus: S.R. Wente; Science 288, 1374 (2000) (Review) 5 Leucine-rich nuclear-export signals: born to be weak: U. Kutay and S. Guttinger; Trends Cell Biol. 15, 121 (2005) (Review) 6 Mechanisms of Recptor-Mediated Nuclear Import and Nuclear Export: L.F. Pemberton and B.M. Paschal; Traffic 6, 187 (2005) (Review) 7 Importin alpha: a multipurpose nuclear-transport receptor: D.S. Goldfarb, et al.; Trends Cell Biol. 14, 505 (2004) (Review) 8 Importin beta: conducting a much larger cellular symphony: A. Harel and D.J. Forbes; Mol. Cell 16, 319 (2004) (Review) 9 Karyopherins: from nuclear-transport mediators to nuclear-function regulators: N. Mosammaparast and L.F. Pemberton; Trends Cell Biol. 14, 547 (2004) (Review) 10 Nucleocytoplasmic shuttling of signal transducers: L. Xu and J. Massague; Nat. Rev. Mol. Cell Biol. 5, 209 (2004) (Review) 11 CRM1 is an export receptor for leucine-rich nuclear export signals: M. Fornerod, et al.; Cell 90, 1051 (1997) 12 CRM1 is responsible for intracellular transport mediated by the nuclear export signal: M. Fukuda, et al.; Nature 390, 308 (1997) 13 Evidence for a role of CRM1 in signal-mediated nuclear protein export: B. Ossareh-Nazari, et al.; Science 278, 141 (1997) 14 Exportin 1 (Crm1p) is an essential nuclear export factor: K. Stade, et al.; Cell 90, 1041 (1997) 15 Nuclear transport and cancer: from mechanism to intervention: T.R. Kau, et al.; Nat. Rev. Cancer 4, 106 (2004) (Review) 16 Leptomycins A and B, new antifungal antibiotics. I. Taxonomy of the producing strain and their fermentation, purification and characterization: T. Hamamoto, et al.; J. Antibiot. (Tokyo) 36, 639 (1983) 17 Leptomycins A and B, new antifungal antibiotics.
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