Background
Ran is a small GTPase of the Ras family that plays a central role in the spacial and temperal organization of eukaryotic cells. During interphase, Ran-GDP localizes to the cytoplasm and Ran-GTP to the nucleus. This polarized localization of Ran ensures its role in nuclear transport. During mitosis, Ran-GTP is chromatin associated, where it promotes spindle assembly and nuclear envolope formation. In S phase, Ran-GTP associates with and inhibits MCM helicase, ensuring precise chromosomal DNA duplication during the cell cycle.
References
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