May regulate the intracellular trafficking of RAN . Promotes guanine nucleotide release from RAN and inhibits binding of new GTP by preventing the binding of the RAN guanine nucleotide exchange factor RCC1 . Regulates the levels of GTP-bound RAN in the nucleus, and thereby plays a role in the regulation of RAN-dependent mitotic spindle dynamics . Enhances the expression of SCN5A at the cell membrane in cardiomyocytes ( ).
Subcellular locations: Nucleus, Cytoplasm, Perinuclear region, Cytoplasm, Cell membrane
May shuttle between the nucleus and cytoplasm.
Isoform 1 and isoform 2 are ubiquitously expressed . Detected in heart and brain .