I needed that little break. Exams have calmed temporarily and I have begun studying in earnest yet again. Now I plan to take a slightly different approach with these updates by moving through the material chronologically, as it was taught. Maybe using this method, I'll be able to refer back and interlink posts more efficiently.
Nuclear import and export is heavily regulated in the cell. Phosphorylation can affect nuclear import: direct phosphorylation o the NLS can inhibit transport. Ran-GTP is another important factor that affects transport. Ran-GTP in the nucleus binds to empty receptors and transport them to the cytoplasm, where they can reload with a piece of cargo. Ran-GAPs in the cytoplasm facilitate the hydrolysis of GTP to GDP, which promotes translocation of Ran-GDP to the nucleus. Once in the nucleus, Ran-GEFs promote the exchange of GDP for GTP. The interaction of the different forms of Ran allow for the recycling of shuttling proteins, allowing them to move proteins in and out of the nucleus.