Diffusion of metabolites and small non-nuclear molecules as well as active, mediated import of protein and export of protein and RNA through the nuclear envelope occurs through nuclear pore complexes or NPC’s. NPC’s contain up to 100 different polypeptides which have a combined mass of about 125 megadaltons. The channel available for passive transport through the NPC is about 9-10 nm in diameter while carrier mediated changes in the NPC result in a ~25 nm channel used for larger, actively transported molecules.
Active transport of molecules through the NPC is a signal-mediated process that is not well understood. Proteins to be exported from the nucleus to cytoplasm contain leucine-rich nuclear export signals (NESs). NESs are recognized by transport receptors belonging to the importin-beta family of proteins. It has been shown that NES export is mediated by CRM 1 (Chromosome Region Maintenance 1), an importin-beta family member that binds NESs, Ran:GTP, and Ran binding protein (RanBP). CRM 1 mediates the nuclear exportation of numerous proteins, including histone deacetylases (HDACs), viral proteins, immunophilins, and STAT 1.
The application notes include recommended starting dilutions; optimal dilutions/concentrations should be determined by the end user.
Use at an assay dependent concentration.
Use a concentration of 0.4 µg/ml. Detects a band of approximately 135 kDa (predicted molecular weight: 119 kDa).Can be blocked with Human CRM1 peptide (ab41768).
Mediates the nuclear export of cellular proteins (cargos) bearing a leucine-rich nuclear export signal (NES) and of RNAs. In the nucleus, in association with RANBP3, binds cooperatively to the NES on its target protein and to the GTPase RAN in its active GTP-bound form (Ran-GTP). Docking of this complex to the nuclear pore complex (NPC) is mediated through binding to nucleoporins. Upon transit of an nuclear export complex into the cytoplasm, disassembling of the complex and hydrolysis of Ran-GTP to Ran-GDP (induced by RANBP1 and RANGAP1, respectively) cause release of the cargo from the export receptor. The directionality of nuclear export is thought to be conferred by an asymmetric distribution of the GTP- and GDP-bound forms of Ran between the cytoplasm and nucleus. Involved in U3 snoRNA transport from Cajal bodies to nucleoli. Binds to late precursor U3 snoRNA bearing a TMG cap. Several viruses, among them HIV-1, HTLV-1 and influenza A use it to export their unspliced or incompletely spliced RNAs out of the nucleus. Interacts with, and mediates the nuclear export of HIV-1 Rev and HTLV-1 Rex proteins. Involved in HTLV-1 Rex multimerization.
Expressed in heart, brain, placenta, lung, liver, skeletal muscle, pancreas, spleen, thymus, prostate, testis, ovary, small intestine, colon and peripheral blood leukocytes. Not expressed in the kidney.
Belongs to the exportin family. Contains 10 HEAT repeats. Contains 1 importin N-terminal domain.
Phosphorylated upon DNA damage, probably by ATM or ATR.
Cytoplasm. Nucleus > nucleoplasm. Nucleus > Cajal body. Nucleus > nucleolus. Located in the nucleoplasm, Cajal bodies and nucleoli. Shuttles between the nucleus/nucleolus and the cytoplasm.