Wed, Jan 12, 2011 @ 03:30 PM - 04:30 PM
Aerospace and Mechanical Engineering
Conferences, Lectures, & Seminars
Speaker: Elisa Franco , Graduate Student
Talk Title: Programming Molecular Networks
Abstract: How do living organisms process information and implement their responses to external stimuli? Even in the simplest cells, sensing, computation and actuation are structurally embedded in the biochemistry of complex molecular networks, and we need to develop new paradigms to explain and engineer such structures. Quoting Richard Feynman, what we cannot create, we do not understand: by programming and building simple molecular networks from the bottom-up, scientists have an opportunity to gain insight into the design principles of more complicated, naturally occurring circuits.
In this talk, I will describe how DNA and RNA can be used as simple building blocks to construct molecular circuits encoding complex functionalities, because their interactions can be predicted and specified with high confidence. In particular, we have used nucleic acids to investigate two challenges: synchronization and scalability of biochemical networks. I will describe how the activity of two synthetic genes can be matched, by using their outputs to create positive or negative feedback loops. Scaling up our perspective, to synchronize the operations of a larger number of circuits we may need \"timing\" devices: for instance, digital clock generators coordinate the state transitions of millions of silicon circuits. I will describe how a tunable synthetic oscillator can be used to time the conformation of a DNA nano-mechanical device called \"DNA tweezers,\" evaluating several modes of connection. Because the biochemical interconnections are created by stoichiometric binding of our oscillator components and its \"load\" components, we observed a remarkable deterioration of the oscillator behavior as we increased its load concentration. To reduce this undesired retroactivity we engineered an \"insulator circuit\", the molecular equivalent of an operational amplifier, which improves the modularity and scalability of the system. To our knowledge, this is the first experimental attempt to use a synthetic biochemical oscillator to drive several types of downstream processes, in a plug-and-play fashion.
Biography: Elisa Franco is currently a graduate student at the California Institute of Technology, in the Department of Control and Dynamical Systems. She got her Laurea degree in Power Systems Engineering from the University of Trieste, Italy, where she also earned a PhD in Automatic Control. Her current research interests are in the field of synthetic and systems biology.
Host: Prof. Eva Kanso
More Info: http://ame-www.usc.edu/seminars/1-12-11-franco.shtml
Location: Seaver Science Library (SSL) - 150
Audiences: Everyone Is Invited
Contact: April Mundy