InnateDB: Systems Biology of the Innate Immune Response

Homo sapiens Protein: KPNA4

Summary

InnateDB Protein

IDBP-63599.5

Last Modified

2014-10-13 [Report errors or provide feedback]

Gene Symbol

KPNA4

Protein Name

karyopherin alpha 4 (importin alpha 3)

Synonyms

IPOA3; QIP1; SRP3;

Species

Homo sapiens

Ensembl Protein

ENSP00000334373

InnateDB Gene

IDBG-63597 (KPNA4)

Protein Structure

UniProt Annotation

Function

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. Recognizes NLSs of influenza A virus nucleoprotein probably through ARM repeats 7-9.

Subcellular Localization

Cytoplasm {ECO:0000250}. Nucleus {ECO:0000250}.

Disease Associations

Tissue Specificity

Ubiquitous. Highest levels in heart and skeletal muscle.

Comments

Interactions

Number of Interactions

This gene and/or its encoded proteins are associated with 40 experimentally validated interaction(s) in this database.
They are also associated with 1 interaction(s) predicted by orthology.