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Nuclear Transport Proteins

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I9781 Importin β1 human ≥80% (SDS-PAGE), recombinant, expressed in E. coli (N-terminal histidine tagged), buffered aqueous glycerol solution Importin β, an import receptor, is a prototype of the nuclear transport receptor family, which comprises in human more than 20 proteins (90-180 kDa). These proteins interact directly with nuclear pore complex (NPC) and mediate nucleocytoplasmic transport. Importin β imports into the nucleus proteins carrying canonical nuclear localization signals (NLS) as well as UsnRNAs, which it binds via adaptor proteins, importin α and snurpotin-1 respectively. Importin β also binds directly, without adaptors, ribosomal proteins, Smad proteins, and virus derived proteins such as HIV Rev and Tat, that contain non classical NLS. In addition, Improtin b has been shown to be involved in the nuclear envelope assembly process.
The mechanism of importin β action in nuclear import can be demonstrated by the well-studied import of proteins containing classical NLS. Importin β forms a complex with Importin α, which, in turn, binds the cargo protein via its NLS. The Impβ/Impα/cargo complex translocates into the nucleus. When the complex reaches the nuclear site of the NPC, Ran-GTP binds the Impβ to form Impβ/Ran-GTP complex and released the Impα and the cargo protein. The Impβ/Ran-GTP complex is then exported to the cytoplasm where the complex dissociates upon hydrolysis of GTP to GDP, making Impβ ready for a new import cycle.
SRP4820 MAGE-1 human recombinant, expressed in E. coli, ≥90% (SDS-PAGE)  
SRP4823 MART-1 human recombinant, expressed in E. coli, ≥90% (SDS-PAGE) Melanoma-associated antigen recognized by T cells-1 (MART-1) has been shown to be essential for the functioning of glycoprotein-100 (gp100).
N9285 Nuclear Transport Factor 2−Agarose saline suspension NTF2 is a small homodimeric protein that interacts simultaneously with both Ran-GDP and FxFG nucleoporins. The interaction between NTF2 and Ran-GDP is essential for the import of Ran into the nucleus, thus crucial for maintaining the cellular nuclear transport and cell viability. NTF2-agarose affinity resin is a useful tool for studying nuclear transport and the depletion of Ran-GDP from cell extracts.
R3152 RAN human >90% (SDS-PAGE), recombinant, expressed in E. coli (N-terminal histidine tagged), buffered aqueous glycerol solution Ran (TC4), a small GTP binding protein, is the heart of the nuclear transport process. It is involved in the directionality of the process that is regulated by GTP hydrolysis. Ran shuttles between the nucleus and the cytoplasm. In the nucleus, it exists in Ran-GTP form, which is maintained by the Ran-Guanine nucleotide exchange protein, RCC1, a nucleus specific, chromatin bound protein. Ran-GTP forms complexes with transport proteins that shuttle from the nucleus to the cytoplasm i.e. improtin β, CRM1/exportin1. In the cytoplasm, Ran intrinsic GTPase activity is stimulated by Ran-GAP causing the hydrolysis of GTP to GDP and disassembly of the resulted Ran-GDP from the transport protein. Ran-GDP reenters the nucleus by active transport as NTF2/Ran-GDP complex.