Marc W. Kirschner
Professor of Systems Biology
In the development of an organism, as in the theater, timing is everything. Imagine if, one night, the actors in a play were to miss every single cue, delivering each line perfectly, but always too early or too late. The evening would be a disaster. The same is true in embryonic development. Starting at the moment when sperm and egg meet, cells in the embryo send signals to each other to coordinate the growth of organs, limbs, and tissues. Not only do the signals have to be correct, they also must be perfectly timed. Otherwise, disasters like cancer can result.
The Kirschner lab studies, among many other things, the way a developing frog embryo orchestrates numerous signals to yield the final, complex organism. Just as multiple cues would destroy an actor's ability to deliver his lines at the right time, it would seem like the existence of multiple signals ought to result in cellular cacophony. But, somehow, the cells in the embryo can sort out the meaning of the different signals that are bombarding them. In particular, the lab is investigating the signals that tell cells when to divide.