核质转运是一个信号和能量依赖的过程，通过核包膜内的核孔复合体进行。含有核定位信号（nls）的蛋白质的输入需要nls输入受体，一种输入素α和β亚单位的异二聚体，也称为核外激素。importinα在细胞质中结合含有nls的货物，importinβ在核孔复合体的细胞质侧停靠复合体。在三磷酸核苷和小gtp结合蛋白ran的存在下，复合物进入核孔复合物，而导入蛋白亚基解离。importinα与它的乘客蛋白一起进入核浆，importinβ留在孔中。β-导入素与核孔蛋白fg重复序列之间的相互作用是通过孔复合体转运的关键。这个基因编码的蛋白质是importinβ家族的一员。已经发现了两个编码不同亚型的转录变体。[由RefSeq提供，2013年2月]
Nucleocytoplasmic transport, a signal- and energy-dependent process, takes place through nuclear pore complexes embedded in the nuclear envelope. The import of proteins containing a nuclear localization signal (NLS) requires the NLS import receptor, a heterodimer of importin alpha and beta subunits also known as karyopherins. Importin alpha binds the NLS-containing cargo in the cytoplasm and importin beta docks the complex at the cytoplasmic side of the nuclear pore complex. In the presence of nucleoside triphosphates and the small GTP binding protein Ran, the complex moves into the nuclear pore complex and the importin subunits dissociate. Importin alpha enters the nucleoplasm with its passenger protein and importin beta remains at the pore. Interactions between importin beta and the FG repeats of nucleoporins are essential in translocation through the pore complex. The protein encoded by this gene is a member of the importin beta family. Two transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Feb 2013]