Wolfgang Driever (Internal Senior Fellow, School of Life Sciences - LifeNet): "If you can do anything, how to make sure you do the right thing at the right time? Stem cells, pluripotency, and developmental timing in the embryo."
von 18:30 bis 19:30
|Wo||FRIAS, Albertstr. 19, Seminarraum|
Decision-making is of utmost importance in every aspect of life, from the level of every single cell in an organism to society as a whole. The core feature of decision-making is the transition between a state in which an entity has the potential to go many different (pluripotent) or even any possible (totipotent) way, and a second state in which the fate is determined and irreversible processes have started. A decision is considered "right" if it comes in the right place and time, and has an outcome that is beneficial for the entity as well as the environment, or even for the system under consideration as a whole. One may argue that the art of decision making entails a state in which the entity is open to influences from the outside and evaluates the signals it receives, keeping all opportunities open for a while, in order to take the "right" decision at the right place and time. Thus, the quality of mechanisms that control the duration of the "undecided" (but pluripotent) phase of evaluation ultimately control the quality of the decision. If the pluripotent state is too short, the wrong decisions are inevitable, if its too long, opportunities are lost because competing entities may make the right decision earlier.
The earliest cells in the embryo are "pluripotent": they have the opportunity to take any fate. The mechanisms used by cells in the embryo to stay in the pluripotent state have been investigated for more than a decade, but the mechanisms used during the decision making state to time the progress of decisions with global development are not understood. Here, I will discuss two mechanisms by which two major regulators, Oct4 and Sox2, make sure that decisions are not made prematurely. I will also emphasize that "place and time" are important for decision making: different major areas of the embryo have evolved variations of mechanisms with regard to decision timing.