Biomedical Engineering Seminar: Analog versus Digital Information Processing in Cellular Systems
Building 193, Electrical and Electronic Engineering Building
T: (03) 8344 6606
Stochasticity is an essential aspect of biochemical processes at the cellular level. We now know that living cells take advantage of stochasticity in some cases and counteract stochastic effects in others.The presenter will use examples to discuss how cells process information and discuss the relative roles that analog and digital signal processing play in cellular systems. In the response of Escherichia coli to nitrogen starvation, for example, researchers find strong evidence for both types of information processing. Using time-resolved proteomic, metabolomic and transcriptomic data researchers can show that the nitrogen state can be computed with high fidelity. The high accuracy - the channel capacity amounts to approximately 10 bits - reflects a strong evolutionary impetus on optimizing sensing and correctly responding to the environmental nitrogen state. Combining different experimental data in a coherent inferential and modelling framework allows researchers to dissect the molecular machinery involved in both the digital and analog signal processing steps employed by the cells. The presenter will conclude by providing a simple perspective on biological information processing and the evolution of signal transduction systems.