Initially known for its ability to promote cell cycle exit, protein p27 has now been found to have other talents. Laurent Nguyen’s team at the GIGA-Neurosciences unit has revealed the involvement of p27 in controlling the migration of cortical interneurons through its action on actin and microtubules.

If we think about the complexity of the human body, the billions of cells composing it, the way in which they are organised and orchestrated to form this perfectly functional whole, it is sometimes difficult to remember that all of this results from one initial cell (this sentence is grammatically correct but do not sound English). But nevertheless, after the fusion of sperm and egg, the first cell starts to divide and the resulting daughter cells will follow suit, and so on. Embryonic cells are undifferentiated cells and they will gradually exit the cell cycle, to specialise and migrate to constitute the various tissues such as the epithelium, muscle, nerve, conjunctive tissue, etc. Every cell reaches its specific location in due course thanks to a vital and highly controlled process: cell migration. If a grain of sand interferes with the process, this can have dramatic consequences on the body’s development preventing it from developing or functioning properly. Depending on the severity of the abnormality and the type of cell concerned, various pathologies may appear. For instance some epilepsy, autism and lissencephaly result from impaired neuron migration during embryogenesis.

(1). Godin, J., Thomas, N., Laguesse, S., Malinouskaya, L., Close, P., Malaise, P., Purnelle, A., Raineteau, O., Campbell, K., Fero, M., Moonen, G., Malgrange, B., Chariot, A., Metin, C, Besson, A., and Nguyen, L.: p27Kip1 is a microtubule-associated protein that promotes microtubule polymerisation during neuron migration.
 Dev Cell (2012), in press.  (details à mettre à jour lors de la parution de l’article)