FEATURES

FAMILY

DESCRIPTION

Also known as IMA5_HUMAN, KPNA1, RCH2. Functions in nuclear protein import as an adapter protein for nuclear receptor KPNB1. Binds specifically and directly to substrates containing either a simple or bipartite NLS motif. Docking of the importin/substrate complex to the nuclear pore complex (NPC) is mediated by KPNB1 through binding to nucleoporin FxFG repeats and the complex is subsequently translocated through the pore by an energy requiring, Ran-dependent mechanism. At the nucleoplasmic side of the NPC, Ran binds to importin-beta and the three components separate and importin-alpha and -beta are re-exported from the nucleus to the cytoplasm where GTP hydrolysis releases Ran from importin. The directionality of nuclear import is thought to be conferred by an asymmetric distribution of the GTP- and GDP-bound forms of Ran between the cytoplasm and nucleus. In vitro, mediates the nuclear import of human cytomegalovirus UL84 by recognizing a non-classical NLS. Heterodimer; with KPNB1 (PubMed:7604027). Interacts with ANP32E (By similarity). Interacts with ZIC3 (By similarity). Interacts with NSMF; the interaction occurs in a calcium-independent manner after synaptic NMDA receptor stimulation and is required for nuclear import of NSMF but is competed by CABP1 (By similarity). Interacts with APEX1 (PubMed:15942031). Interacts with RAG1 (PubMed:8052633). Interacts with CTNNBL1 (via its N-terminal) (PubMed:21385873). Interacts with AICDA (via its NLS) (PubMed:21385873). Interacts with SNAI1 (via zinc fingers) (PubMed:21454664). Interacts with DCAF8 (PubMed:22500989). Interacts with ITSN1 isoform 2 (PubMed:29599122). Interacts with TALDO1 isoform 1 (By similarity).

EXTERNAL LINKS

KPNA1

Importin subunit alpha-5

KPNA1

Molecular Synopsis