Search Results

Overview

Uniprot ID	O00629
Protein Name	Importin subunit alpha-3
Gene Name	KPNA4
Organism	Homo sapiens

Kla Sites from experimental identification

Position	Flanking peptide
47	KRDEHLLKRRNVPHE

Function

Functions in nuclear protein import as an adapter protein for nuclear receptor KPNB1 (PubMed:10567565, PubMed:20818336, PubMed:28760339, PubMed:29042532, PubMed:38512451). Binds specifically and directly to substrates containing either a simple or bipartite NLS motif (PubMed:20818336, PubMed:28760339, PubMed:29042532, PubMed:38512451). 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 (PubMed:20818336, PubMed:28760339, PubMed:29042532, PubMed:38512451). 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 (PubMed:20818336, PubMed:28760339, PubMed:29042532, PubMed:38512451). 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 (PubMed:20818336, PubMed:28760339, PubMed:29042532, PubMed:38512451). Mediates nuclear import of AARS1, MRTFA and RANBP3 (PubMed:10567565, PubMed:20818336, PubMed:28760339, PubMed:38512451)

Protein Sequence

10 MADNEKLDNQ 20 RLKNFKNKGR 30 DLETMRRQRN 40 EVVVELRKNK 50 RDEHLLKRRN 60 VPHEDICEDS 70 DIDGDYRVQN 80 TSLEAIVQNA 90 SSDNQGIQLS 100 AVQAARKLLS 110 SDRNPPIDDL 120 IKSGILPILV 130 HCLERDDNPS 140 LQFEAAWALT 150 NIASGTSEQT 160 QAVVQSNAVP 170 LFLRLLHSPH 180 QNVCEQAVWA 190 LGNIIGDGPQ 200 CRDYVISLGV 210 VKPLLSFISP 220 SIPITFLRNV 230 TWVMVNLCRH 240 KDPPPPMETI 250 QEILPALCVL 260 IHHTDVNILV 270 DTVWALSYLT 280 DAGNEQIQMV 290 IDSGIVPHLV 300 PLLSHQEVKV 310 QTAALRAVGN 320 IVTGTDEQTQ 330 VVLNCDALSH 340 FPALLTHPKE 350 KINKEAVWFL 360 SNITAGNQQQ 370 VQAVIDANLV 380 PMIIHLLDKG 390 DFGTQKEAAW 400 AISNLTISGR 410 KDQVAYLIQQ 420 NVIPPFCNLL 430 TVKDAQVVQV 440 VLDGLSNILK 450 MAEDEAETIG 460 NLIEECGGLE 470 KIEQLQNHEN 480 EDIYKLAYEI 490 IDQFFSSDDI 500 DEDPSLVPEA 510 IQGGTFGFNS 520 SANVPTEGFQ F

Gene Ontology

Classification	GO ID	Description
Cellular Component	GO:0005737	cytoplasm
Cellular Component	GO:0005829	cytosol
Cellular Component	GO:0042564	NLS-dependent protein nuclear import complex
Cellular Component	GO:0005643	nuclear pore
Cellular Component	GO:0005654	nucleoplasm
Cellular Component	GO:0005634	nucleus
Molecular Function	GO:0061608	nuclear import signal receptor activity
Molecular Function	GO:0008139	nuclear localization sequence binding
Biological Process	GO:0006607	NLS-bearing protein import into nucleus
Biological Process	GO:0006606	protein import into nucleus

Reference

[1] Yang D, Yin J, Shan L, Yi X, Zhang W et al.. Identification of lysine-lactylated substrates in gastric cancer cells.. iScience 25(7):104630. 2022 Jul 15. PMID: 35800753.

[2] Yang Z, Yan C, Ma J, Peng P, Ren X et al.. Lactylome analysis suggests lactylation-dependent mechanisms of metabolic adaptation in hepatocellular carcinoma.. Nat Metab 5(1):61-79. 2023 Jan. PMID: 36593272.

[3] Shi CM, Wang QC, Li XL, Yang YH, Tang XY et al.. Global Profiling of Protein Lactylation in Human Hippocampi.. Proteomics Clin Appl 19(2):e202400061. 2025 Mar. PMID: 39610256.

[4] Wu Q, Li Z, Gong T, Zheng X, Zhou X et al.. Porphyromonas gingivalis infection induces lysine lactylation reprogramming in human umbilical vein endothelial cells.. Front Cell Infect Microbiol 16:1706727. 2026. PMID: 41696360.