KPNA4（karyopherin subunit alpha 4），癌症关联基因，基因ID：3840，亲核蛋白的核导入是由称为核定位信号（nlss）的短氨基酸序列控制的。核地鼠素，或称为重要蛋白，是一种细胞质蛋白质，能识别NLS并将含有NLS的蛋白质连接到核孔复合体上该基因编码的蛋白质与非洲爪蟾输入素α和酿酒酵母Srp1具有序列相似性该蛋白与dna螺旋酶q1和sv40 t抗原的nlss相互作用。[由RefSeq提供，2008年7月]The nuclear import of karyophilic proteins is directed by short amino acid sequences termed nuclear localization signals (NLSs). Karyopherins， or importins， are cytoplasmic proteins that recognize NLSs and dock NLS-containing proteins to the nuclear pore complex. The protein encoded by this gene shares the sequence similarity with Xenopus importin-alpha and Saccharomyces cerevisiae Srp1. This protein is found to interact with the NLSs of DNA helicase Q1 and SV40 T antigen. [provided by RefSeq， Jul 2008]。