Descriptions

Importin-α is a nuclear import receptor that facilitates the transport of proteins with nuclear localization sequences (NLSs) into the nucleus. It is autoinhibited by its N-terminal region, which occupies the NLS-binding site, preventing unnecessary binding and import activity. Importin-α is autoinhibited in the absence of importin-β and the binding of importin-β alleviates this autoinhibition, which displaces the autoinhibitory sequence.

Autoinhibitory domains (AIDs)

Target domain

139-231 (Major NLS-binding site);307-396 (Minor NLS-binding site)

Relief mechanism

Partner binding

Assay

Accessory elements

No accessory elements

Autoinhibited structure

Activated structure

1 structures for O22478

Entry ID Method Resolution Chain Position Source
AF-O22478-F1 Predicted AlphaFoldDB

No variants for O22478

Variant ID(s) Position Change Description Diseaes Association Provenance
No variants for O22478

No associated diseases with O22478

6 regional properties for O22478

Type Name Position InterPro Accession
repeat Armadillo 105 - 231 IPR000225-1
repeat Armadillo 233 - 314 IPR000225-2
repeat Armadillo 316 - 399 IPR000225-3
repeat Armadillo 402 - 442 IPR000225-4
domain Importin-alpha, importin-beta-binding domain 1 - 95 IPR002652
repeat Atypical Arm repeat 457 - 500 IPR032413

Functions

Description
EC Number
Subcellular Localization
  • Cytoplasm
PANTHER Family
PANTHER Subfamily
PANTHER Protein Class
PANTHER Pathway Category No pathway information available

2 GO annotations of cellular component

Name Definition
cytoplasm The contents of a cell excluding the plasma membrane and nucleus, but including other subcellular structures.
nucleus A membrane-bounded organelle of eukaryotic cells in which chromosomes are housed and replicated. In most cells, the nucleus contains all of the cell's chromosomes except the organellar chromosomes, and is the site of RNA synthesis and processing. In some species, or in specialized cell types, RNA metabolism or DNA replication may be absent.

2 GO annotations of molecular function

Name Definition
nuclear import signal receptor activity Combining with a nuclear import signal (NIS) on a cargo to be transported, to mediate transport of the cargo through the nuclear pore, from the cytoplasm to the nuclear lumen. The cargo can be either a RNA or a protein.
nuclear localization sequence binding Binding to a nuclear localization sequence, a specific peptide sequence that acts as a signal to localize the protein within the nucleus.

1 GO annotations of biological process

Name Definition
NLS-bearing protein import into nucleus The directed movement of a protein bearing a nuclear localization signal (NLS) from the cytoplasm into the nucleus, across the nuclear envelope.

30 homologous proteins in AiPD

UniProt AC Gene Name Protein Name Species Evidence Code
Q02821 SRP1 Importin subunit alpha Saccharomyces cerevisiae (strain ATCC 204508 / S288c) (Baker's yeast) SS
A2VE08 KPNA1 Importin subunit alpha-5 Bos taurus (Bovine) SS
C1JZ66 KPNA7 Importin subunit alpha-8 Bos taurus (Bovine) PR
Q0V7M0 KPNA6 Importin subunit alpha-7 Bos taurus (Bovine) SS
Q5ZML1 KPNA1 Importin subunit alpha-5 Gallus gallus (Chicken) SS
P52295 Pen Importin subunit alpha Drosophila melanogaster (Fruit fly) SS
A9QM74 KPNA7 Importin subunit alpha-8 Homo sapiens (Human) EV
O00505 KPNA3 Importin subunit alpha-4 Homo sapiens (Human) SS
O00629 KPNA4 Importin subunit alpha-3 Homo sapiens (Human) SS
O15131 KPNA5 Importin subunit alpha-6 Homo sapiens (Human) SS
O60684 KPNA6 Importin subunit alpha-7 Homo sapiens (Human) SS
P52292 KPNA2 Importin subunit alpha-1 Homo sapiens (Human) EV
P52294 KPNA1 Importin subunit alpha-5 Homo sapiens (Human) SS
P52293 Kpna2 Importin subunit alpha-1 Mus musculus (Mouse) EV
C0LLJ0 Kpna7 Importin subunit alpha-8 Mus musculus (Mouse) SS
O35343 Kpna4 Importin subunit alpha-3 Mus musculus (Mouse) SS
O35344 Kpna3 Importin subunit alpha-4 Mus musculus (Mouse) SS
O35345 Kpna6 Importin subunit alpha-7 Mus musculus (Mouse) PR
Q60960 Kpna1 Importin subunit alpha-5 Mus musculus (Mouse) SS
C6K7I2 KPNA7 Importin subunit alpha-8 Sus scrofa (Pig) SS
P83953 Kpna1 Importin subunit alpha-5 Rattus norvegicus (Rat) SS
Q56R16 Kpna5 Importin subunit alpha-6 Rattus norvegicus (Rat) SS
Q71VM4 Os01g0253300 Importin subunit alpha-1a Oryza sativa subsp. japonica (Rice) SS
P91276 ima-2 Importin subunit alpha-2 Caenorhabditis elegans SS
Q19969 ima-3 Importin subunit alpha-3 Caenorhabditis elegans SS
Q9FWY7 IMPA6 Importin subunit alpha-6 Arabidopsis thaliana (Mouse-ear cress) SS
O04294 IMPA3 Importin subunit alpha-3 Arabidopsis thaliana (Mouse-ear cress) SS
Q9FJ09 IMPA5 Importin subunit alpha-5 Arabidopsis thaliana (Mouse-ear cress) SS
Q9M9X7 IMPA7 Importin subunit alpha-7 Arabidopsis thaliana (Mouse-ear cress) SS
Q503E9 kpna5 Importin subunit alpha-6 Danio rerio (Zebrafish) (Brachydanio rerio) SS
10 20 30 40 50 60
MSLRPNSRTE ARRSRYKVAV DAEEGRRRRE DNMVEIRKNK REENLLKKRR EGLLQAQQFP
70 80 90 100 110 120
STAAVSHLDK KLETLPELIA GVWSDDSSLQ LECTTQFRKL LSIERNPPIE EVIQSGVVPR
130 140 150 160 170 180
FVEFLARDDY PQLQFEAAWA LTNIASGTSE NTKVVIDYGS VPIFIRLLSS PSDDVREQAV
190 200 210 220 230 240
WALGNIAGDS PKYRDLVLGH GALVALLAQF NEQAKLSMLR NATWTLSNFC RGKPQPLFEQ
250 260 270 280 290 300
TKAALPTLGR LIHSNDEEVL TDACWALSYL SDGTNDKIQA VIEAGVCSRL VELLLHSSPS
310 320 330 340 350 360
VLIPALRTVG NIVTGDDIQT QVMIDHHALP CLVNLLTQNY KKSIKKEACW TISNITAGNR
370 380 390 400 410 420
NQIQIVIEAG IIAPLVYLLQ NAEFEIKKEA AWAISNATSG GNHDQIKFLV SQGCIKPLCD
430 440 450 460 470 480
LLVCPDPRIV TVCLEGLENI LKIGEADKDL GNTEGVNVYA QLIDEAEGLE KIENLQSHDN
490 500 510 520
TEIYEKAVKI LETYWLEEED VPVSLNEDQF EFGGADISLP SGGFNFS