KPNA1

Recombination activating proteins RAG1 and RAG2 regulate and mediate V(D)J recombination, the process by which genes for immunoglobulins and T-cell receptors are generated. Several other ubiquitously expressed proteins are thought to be recruited in the recombination process. Among these are the genes affected in severe combined immune deficiency and genes involved in ds-DNA break repair. The protein encoded by this gene interacts with RAG1 and may play a role in V(D)J recombination. Two transcript variants, one protein-coding and the other not, have been found for this gene. [provided by RefSeq]

Full Name

karyopherin alpha 1 (importin alpha 5)

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.

Biological Process

NLS-bearing protein import into nucleusManual Assertion Based On ExperimentIBA:GO_Central
Postsynapse to nucleus signaling pathwayManual Assertion Based On ExperimentIBA:GO_Central
Regulation of apoptotic processIEA:Ensembl
Regulation of canonical Wnt signaling pathwayIEA:Ensembl
Regulation of DNA recombinationManual Assertion Based On ExperimentTAS:ProtInc
Satellite cell activation involved in skeletal muscle regenerationIEA:Ensembl
Skeletal muscle satellite cell proliferationIEA:Ensembl

Cellular Location

Cytoplasm
Nucleus

PTM

Polyubiquitinated in the presence of RAG1 (in vitro).