a guanine-nucleotide releasing factor that promotes the exchange of Ran-bound GDP for GTP. Localised generation of Ran-GTP by RCC1 on chromatin is critical for nucleocytoplasmic transport, mitotic spindle assembly and nuclear envelope formation. Involved in the regulation of onset of chromosome condensation in the S phase. Binds both to the nucleosomes and double-stranded DNA. RCC1-Ran complex (together with other proteins) acts as a component of a signal transmission pathway that detects unreplicated DNA. Plays a key role in nucleo- cytoplasmic transport, mitosis and nuclear-envelope assembly. Interacts with ARRB2; the interaction is detected in the nucleus upon OR1D2 stimulation. 2 isoforms of the human protein are produced by alternative splicing. Note: This description may include information from UniProtKB.
Protein type: Cell cycle regulation; GEF; GEF, Ras