Table 2 Members of broad sense karyopherins
From: Nuclear transport proteins: structure, function and disease relevance
Name (abbrv) | Synonyms | Cargo examples | Binding motif/domain | Cargo clustering | |
|---|---|---|---|---|---|
Importin | Importin β1 (Impβ1/Impβ) | KPNB1, Kapβ1, | Many cargoes through the adaptors Impα1 and Snurportin, SREBP-2, NFκB, TFEB, PD-L1 | A basic helix by IBB, globular domains | DNA synthesis, DNA repair, gene expression regulation |
Transportin 1 (TNPO1/TRN1) | Kapβ2 | hnRNP A1, TDP-43, FUS, β-catenin, BAP1 | Linear PY-NLS, RGG domain, poly PR peptide | RNA processing, nuclear division, tRNA ligases | |
Transportin 2 (TNPO2/TRN2) | IPO3, Imp3 | hnRNP A1, TDP-43, FUS | Linear PY-NLS, | RNA processing, DNA repair, HMG proteins | |
Transportin 3 (TNPO3) | TrnSR2, TNPO-SR | ASF/SF2, CPSF6, CIRBP, HIV virus, | Linear motif R(pS/D/E)R(pS/D/E) | Transcription elongation, mRNA splicing and export | |
Importin 4 (IPO4/Imp4) | RanBP4 | Histones H3 and H4, Vitamin D Receptor, CEBPD | LPPRS(G/P)P linear motifs, histone H3-H4 globular domain | DNA metabolic processes, chromosome organization | |
Importin 5 (IPO5/Imp5) | RanBP5, KPNB3 | Ribosomal proteins, histone H3, influenza A virus RNA polymerase subunit PB1, DSCAM | Linear motif KP(K/Y)LV | Ribosomal biosynthesis | |
RanBP6 | STAT3 | ||||
Importin 7 (IPO7/Imp7) | RanBP7 | Histone H1, HIV reverse transcription complex (RTC), Smad1, Yap1, DNA plasmids | Disordered histone tail | mRNA splicing factors, snRNPs, HMG proteins | |
Importin 8 (IPO8/Imp8) | Smads, eIF4E, microRNAs | mRNA splicing factors, ribosomal proteins | |||
Importin 9 (IPO9/Imp9) | RanBP9 | ARID3A, PFKP, histones H2A and H2B. | Histone H2A-H2B globular domain | Ribosomal proteins or mRNA splicing factors. | |
Importin 11 (IPO11/Imp11) | BZW1/2, β-catenin, PTEN. | Developmental processes | |||
Exportin | Exportin 1 (XPO1, Exp1) | CRM1 | p53, FOXO, Survivin, TFEB, cGAS. | Linear NES motif Φ-X1–3-Φ-X1–3-Φ-X1–3-Φ. | A broad spectrum of cargoes |
Exportin 2 (XPO2) | CAS, Cse1, Cse1L | Impα1–7 | Globular domain | Impα only | |
Exportin t (XPOT) | Mature tRNA | tRNA stem and two ends | Mature tRNA only | ||
Exportin 5 (XPO5) | Pre-miRNA, tRNA, hairpin RNA, RNA coexported proteins | The stem and 3’ overhang | Some double-stranded RNAs | ||
Exportin 6 (XPO6) | Actin | ||||
Biportin | Importin 13 (IPO13) | Import GR, Mago-Y14, Ubc9, PDCD5, export eIF1A | Globular domains of Mago-Y14, Ubc9, and eIF1A | Chromatin modification, chromatin remodeling, and transcription. | |
Exportin 4 (XPO4) | Sox2, SRY, PKM2, Smad, eIF5A, a subset of circRNAs in metazoans | Globular domains of eIF5A | RNAP II elongation factors, mRNA processing factors. | ||
Exportin 7 (XPO7) | RhoGAP1, 14-3-3sigma, p65 | Basic folded domains | Diverse functions. | ||
RanBP17 | |||||
Smaill size | NTF2 | Ran, CapG | GDP-bound Ran | Import of Ran and piggyback proteins | |
NXF1 family | TAP | mRNA, piRNA | Nuclear export of different RNAs | ||
Hikeshi | Hsp70 | Full length protein | Only Hsp70 import | ||
Adaptor | Importin α family | KPNA1/Impα5, KPNA2/Impα1, KPNA3/Impα4, KPNA4/Impα3, KPNA6/Impα7, KPNA7/Impα8, | NFκB, STATs, eVP24, PB2 | Classical NLS containing one or two stretch(s) of polyK/R sequences | Broad range of cargoes |
Snurportin | Snurportin 1 | m3G-capped U snRNPs | m3G-capped U snRNPs |
