Karyopherin Beta (KPNb1)

IMB1; IPOB; Impnb; Impnb; IPO1; NTF97; PTAC97; Importin subunit beta-1; Importin-90; Nuclear factor p97; Pore targeting complex 97 kDa subunit

SPN	S061
HGNC	6400
MGI	107532
PubMed	23906023
RGD	2909
UniProt	Q14974
Wiki	KPNB1

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. KPNb1 is a member of the importin beta family.

Reference

"Sequence and characterization of cytoplasmic nuclear protein import factor p97."
J. Cell Biol. 130:265-274(1995) [PubMed] [Europe PMC] [Abstract]

"Two different subunits of importin cooperate to recognize nuclear localization signals and bind them to the nuclear envelope."
Curr. Biol. 5:383-392(1995) [PubMed] [Europe PMC] [Abstract]

"Complete sequencing and characterization of 21,243 full-length human cDNAs."
Nat. Genet. 36:40-45(2004) [PubMed] [Europe PMC] [Abstract]

"DNA sequence of human chromosome 17 and analysis of rearrangement in the human lineage."
Nature 440:1045-1049(2006) [PubMed] [Europe PMC] [Abstract]

"The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC)."
Genome Res. 14:2121-2127(2004) [PubMed] [Europe PMC] [Abstract]

"The conserved amino-terminal domain of hSRP1 alpha is essential for nuclear protein import."
EMBO J. 15:1818-1825(1996) [PubMed] [Europe PMC] [Abstract]