Importin β1 (E1F1E) Rabbit mAb #51186

Importins belong to the karyopherin family of nuclear transport proteins (1) and are divided into two subgroups: importin α and importin β. Importins mainly function in nuclear protein import and export (2,3). Importin β1 (also known as karyopherin β1, Kpnβ1, Kpnb1, or p97) plays a key role in the nuclear import process (1-3). Nuclear import via importin β1 association with adaptor importin α (also known as karyopherin α, or Kpnα) is an essential component of the classical nuclear localization signal (NLS) pathway (4). Importin α directly recognizes the NLS present in the cargo target, prompting complex formation with importin β1. The cargo:importin α:importin β1 complex is transported across the nuclear pore complex (NPC) into the nucleus, where it is dissociated by the binding of RanGTP (1-4). Nuclear import directly via importin β1 can also occur by importin β1 recognition of the cargo protein, bypassing importin α involvement. In both cases, the importin β1/target protein interaction is mediated through the binding of importin β1 HEAT repeats with the target protein sequences (either the cargo protein itself or importin α) (5).