Function
Importins (IPO) mediate the import of cellular proteins into the nucleus by binding to the nuclear localization signal (NLS). IPO has 2 subunits: α and β. IPO-α is an adaptor protein which binds the NLS. Proteins can contain one or two NLS motifs. IPO-α contains several armadillo repeats with two NLS-binding sites and an IPO-β binding site (IBB). IPO-β contains 19 HEAT repeats. Many nuclear proteins contain Phe-Gly sequences which can bind to HEAT repeats and thus be transported. See also Protein Transport Membrane Protein.
Disease
Relevance
Structural highlights
