Speaker
Description
In living systems thermal motions become dominant at the nanometre scale, thus protein diffusion must play an important role in cells. But how can stochastic motions at the molecular scale add up to create the exquisite order observed at the cellular scale? I will present the case of Bicoid, a protein whose concentration acts as a postal code in the fly embryo, by letting cells know what is their exact location. The diffusion of Bicoid across the embryo drives the robust and precise formation of a large-scale concentration gradient, as envisioned by Francis Crick in 1970. Further, the diffusion of Bicoid while searching for its binding sites on the DNA controls how quickly and precisely each cell in the embryo can “read” the gradient concentration. Bicoid is thus a perfect example of how protein diffusion in cells can both drive exquisitely precise pattern formation and support the very rapid transmission of information.
