Biomathematics / Computational Biology Colloquium

Oscillatory timeseries data sheds light on molecular mechanisms of circadian timekeeping

Speaker: Jaekyoung Kim, Department of Mathematical Sciences, Korea Advanced Institute of Science and Technology

Location: Warren Weaver Hall 1314

Date: Tuesday, April 21, 2020, 12:30 p.m.

Synopsis:

The circadian (~24h) clock is a self-sustained oscillator, which times diverse behavioral, physiological, and developmental process including our sleep cycle. The key oscillatory mechanism of the clock is a transcriptional-translational negative feedback loop. The suppression of the feedback loop occurs at the same time every day to maintain circadian period although it involves daily nuclear entry of thousands of clock molecules after diffusion through a crowded cytoplasm. Furthermore, the circadian period is robust to environmental temperature change altering reaction rates, which has been a mystery for last 60 years. In this talk, I will describe how we identified underlying molecular mechanisms for such robust rhythms by analyzing the spatio-temporal timeseries data of clock molecules. Furthermore, I will illustrate a systemic modeling approach which identifies the key molecular connection between the circadian clock and tumorigenesis system from solely their oscillatory timeseries data. Finally, I will talk about whether the fitting of ODE models to oscillatory timeseries data is always possible as long as the number of parameters is large (i.e. whether von Neumann's elephants are true).