Table 1 Proteins in the importin-β-like family and their cargoes

Importins

   Importin β (Kap β1, p97, PTACβ) [L39793]

Kap95p [AAB67265]

Ribosomal proteins (H.s.) [31], viral proteins [29], cyclin B1 (X.l. and

H.s.) [32,33], Smad proteins (H.s.) [34], T-cell protein tyrosine phos-

phatase (H.s.) [28]. Adaptors: importin α: cNLS-containing proteins

(reviewed in [1]); importin α/4E-T: eukaryotic translation initiation

factor 4E (H.s.) [78]; snurportin: m³G-capped U snRNPs (H.s.) [25]

XRIP α: RPA (X.l.) [26]

   Transportin 1 (importin β2, karyopherin β2)

hnRNP protiens (A1, F) (H.s.) [39,42]; ribosomal proteins (H.s.) [31]

[U70322]

Kap104p [CAA84959]

Nab2p (S.c.) and Hrp1p (S.c.) [38]

   Transportin-SR (transportin-SR2 & Mtr10a)

SR domain proteins (H.s.) [43,44]

[AJ133769]

   Importin 5 (RanBP5, karyopherin β3)

Ribosomal proteins (H.s.) [31]

[U72761]

Kap108p/SXM1 [AAB64837]

Lhp1p (S.c.) & ribosomal proteins (S.c.) [79]

Kap111p/Mtr10p [CAA99366]

Npl3p (S.c.) [80]

Kap114p/YGL241W [CAA96960]

TBP (S.c.) [45]

   Importin 7 (RanBP7) [AF098799]

Ribosomal proteins (H.s) [31]; mediates import of histone H1 (H.s.)

[27] when bound to importin β

Kap119p/Nmd5p [CAA89663]

Hog1p (S.c.) [58], TFIIS (S.c.) [81]

Kap121p/Pse1p [CAA89141]

Pho4p (S.c.) [82], ribosomal proteins (S.c.) [36], Spo12p (S.c.) [83]

Kap122p/Pdr6p [CAA96716]

Toa1p and Toa2p (S.c.) [84]

Kap123p/Yrb4 [AAC03208]

Ribosomal protein (S.c.) [36,37]

Kap142p/Msn5p [AAB64771]

Replication protein A (S.c.) [65]

   Importin 11 [from ESTAA082435]

UbcM2 (murine) [3]

Exportins

   Exportin 1 (CRM1, XPO1) [Y08614]

Crm1p/Xpo1p [CAA97246]

NES-containing proteins [46,47,48,49,52,54,55], m7G-capped U snRNAs

(X.l.) [53], snurportin 1 [H.s] [51], IκBα (avian) [50], Ssb1p (S.c.) [59],

Ace2p (S.c.) [57], Yap1p (S.c.) [56], Hog1p (S.c.) [58]

   CAS [U33286]

Cse1p/Kap109p [CAA96957]

Importin α (H.s. and S.c.) [60,61,62,63]

   Exportin-t [AF039022 ]

Los1p [CAA82050]

tRNA (H.s. and S.c.) [66,67,68]

   Exportin 4 [AF145021]

eIF-5A (H.s.) [85]

Kap142p/Msn5p [AAB64771]

Pho4p (S.c.) [64], Mig1p (S.c.) [86], Far1p (S.c.) [87], Ste5p (S.c.) [88]

Examples of orphan importins/exportins

   Transportin 2 (karyopherin β2b) [AF019039]

Unknown

   RanBP6 [AF039023]

Unknown

   RanBP8 [U77494]

Found in a complex with importin β, unknown function [89]

   RanBP13 (Mtr10b) [AF267987]

Unknown

   RanBP16 [AF064729]

Unknown

   RanBP17 [AF222747]

Unknown

Kap120p/Lph2p [AAB68237]

Unknown