Importin subunit beta-1 (KPNB1) (KPNB1)

Importin subunit beta-1 (KPNB1) is a central mediator of the nuclear import pathway, belonging to the karyopherin family of transport receptors (UniProt P52292). It facilitates the translocation of various proteins across the nuclear envelope by recognizing nuclear localization signals (NLS) on cargo molecules, often in conjunction with an adapter protein like importin alpha. Once inside the nucleus, the complex is dissociated by the binding of Ran-GTP, allowing the cargo to perform its regulatory functions. KPNB1 is frequently upregulated in various malignancies, including breast, lung, and prostate cancers, where it drives the nuclear accumulation of oncogenic factors that promote cell survival and proliferation (PubMed: 29339366). Due to its critical role in both cancer progression and viral replication—by importing viral genomes or proteins—KPNB1 is an attractive target for therapeutic intervention. Small molecule inhibitors such as ivermectin and importazole have shown efficacy in preclinical models by disrupting this transport mechanism and inducing cell cycle arrest or apoptosis (PubMed: 32251768, 21135137).

Other names

Karyopherin subunit beta-1Karyopherin beta-1IMB1NTF97Importin-90

Inhibition of nuclear import by blocking the interaction between importin beta-1 and its cargo or the nuclear pore complex (PubMed: 21135137, 32251768).