[1] Importin α is known to bind to the nuclear localization signal (NLS) sequence of nucleus targeted proteins.
[4] The majority of the importin α protein is made up of a series of ten tandem armadillo, or ARM, repeats.
The IBB domain of importin α molecules contain many basic amino acid residues, similar to those found in NLS sequences.
[9] Additionally, Importin α import has been shown to regulated protease function, including that of Taspase1, a degrader of leukemia proteins.
Studies have linked importin α with the recognition and import of some viral nucleoproteins, including those of the influenza A virus.
[15] It has been discovered that the Influenza A virus accesses this host machinery via a NLS like sequence toward the N-terminus of the viral nucleoprotein that can be recognized by importin α class proteins.
Because of this structural similarity, influenza A viral nucleoprotein is able to be imported into the nucleus of its host and take over replication machinery to proliferate.