Peptide ELISA: Limit dilution 1: 32000. Western blot: 1-3 μg/mL. Approx 60 kDa band observed in lysates of cell lines HEK293, HeLaand HEPG2 (calculated MW of 60.0 kDa according to NP_002255.1).
Protein transfer into and out of the nucleus occurs through the nuclear pore complex (NPCs). Karyopherin, a cytosolic, heterodimeric protein complex consisting of alpha and beta subunits, is responsible for targeting proteins with nuclear localization signals to the nuclear pore complex. SRP1 (nucleoprotein interactor 1, NPI 1) is the alpha subunit of karyopherin, which acts as the receptor for the targeted protein's nuclear localization signal (Moroianu J. Crit 1997). Both subunits of karyopherin are required for protein docking at the NPC, the alpha subunit binds the substrate and the beta subunit acts as an adaptor (Moroianu J, et al. 1995). Two other proteins, p10 and the GTPase Ran, are also required for the translocation of docked proteins to the nucleus. The karyopherin dimer dissociates during import, a process mediated by RanGTP, which binds to karyopherin ß and promotes the release of both subunits from the docking site (Moroianu J. Crit 1997). The alpha subunit and imported substrate enter the nucleus and accumulate in the nucleoplasm, while the beta subunit accumulates at the NPC (Moroianu J. Crit 1997)Synonyms: IPOA5, Karyopherin alpha 1, NPI-1, Nucleoprotein interactor 1, RAG cohort protein 2, RCH2, SRP1, SRP1-beta