Zipcode for the Control Center: For a protein to find its way to the nucleus of a cell, where it can turn on or off genes, it must carry a special code, known as Nuclear Localization Signal (NLS). Carriers, known as importins, recognize the NLS, and escort the protein through the nuclear pores into the nucleus. The importins themselves must be recovered by yet another system of on-off switches, the Ran proteins, driven by the breakdown of GTP.
In the video, fluorescent NLS cycles in and out of the nuclei of a dividing Drosophila embryo. The action appears coordinated because in insects, the early nuclear divisions occur without cell division creating a syncytium. These nuclear divisions are extremely rapid, occurring about every 8 minutes.
This beautiful Cell Dance is choreographed to Oxygene by Jean-Michel Jarre. If you liked the clip, watch their performance: Jean Michel Jarre – Oxygene IV