importin 9 (Ran-binding protein 9, RanBP9, HSPC273, IPO9, IMP9, KIAA1192)

Function: - nuclear protein import as nuclear transport receptor - receptor for nuclear localization signals (NLS) in cargo substrates - thought to mediate docking of importin/substrate complex to the nuclear pore complex through binding to nucleoporin - the complex is subsequently translocated through the pore by an energy requiring, Ran-dependent mechanism - at the nucleoplasmic side of the nuclear pore complex, Ran binds to the importin, the importin/substrate complex dissociates & importin is re-exported from the nucleus to the cytoplasm where GTP hydrolysis releases Ran - directionality of nuclear import is thought to be conferred by an asymmetric distribution of the GTP- & GDP-bound forms of Ran between the cytoplasm & nucleus - mediates nuclear import of H2B histone (putative), RPS7 & RPL18A - prevents cytoplasmic aggregation of RPS7 & RPL18A by shielding exposed basic domains - may also import H2A, H3, H4 histones (putative), RPL4 & RPL6 - binds with high affinity to RPS7 & RPL18A - binding is coupled to RanGTP cycles - may bind H2A, H3, H4 histones, RPL4 & RPL6 with low affinity - interacts with PPP2R1A & PPP2R1B Structure: - belongs to the importin beta family - contains 1 importin N-terminal domain Compartment: cytoplasm (putative), nucleus Note: - one of two Ran-binding protein 9 - Ran-binding protein M is the other

Related

importin complex (NLS-binding protein) Ran-binding protein M; Ran-binding protein 9; RanBP9; BPM-L; BPM90; RanBPM; RanBP7 (RANBP9, RANBPM)

Properties

SIZE: MW = 116 kD entity length = 1041 aa COMPARTMENT: cytoplasm cell nucleus MOTIF: Importin N-terminal {43-119} binding site FOR-BINDING-OF: nuclear membrane

Database Correlations

UniProt Q96P70 Pfam PF03810 Kegg hsa:5570

References

UniProt :accession Q96P70