Beijing Computational Science Research Center

Professor Yu-Hai Tu

IBM T. J. Watson Research Center

Yorktown Heights, NY 10598

Abstract: Living organisms need to encode and process information accurately in order to make decisions critical for their survival. Although much progress have been made in identifying key components responsible for various biological functions, it remains a major challenge to understand system-level behaviors from the molecular-level knowledge of biology and to unravel possible design principles for the underlying biochemical circuits. In this talk, we will present some of our recent theoretical/modeling work [1-4] in collaboration with several experimental groups to understand the chemical sensory system in E. coli. We focus on addressing several system-level questions on E. coli’s information processing and decision making processes: 1) How does E. coli encode a memory of its past experience? 2) How does a cell compute chemical gradient accurately in a wide range of backgrounds? 3) How much is the energy cost of regulating the chemotaxis signaling circuit?

References:

[1] “The energy-speed-accuracy trade-off in sensory adaptation”, G. Lan, P. Sartori, S. Neumann, V. Sourjik, Yuhai Tu, Nature Physics, March 2012.

[2] “Adapt locally and act globally: strategy to maintain high chemoreceptor sensitivity in complex environments”, G. Lan, S. Schulmeister, V. Sourjik, Yuhai Tu, Molecular Systems Biology 7:475, 2011.

[3] “A modular gradient-sensing network for chemotaxis in E. colirevealed by responses to time-varying stimuli”, T. S. Shimizu, Yuhai Tu, and Howard C. Berg, Molecular Systems Biology 6: 382, 2010.

[4] “Modeling the chemotactic response of E. coli to time-varying stimuli”, Y. Tu, T. S. Shimizu and H. Berg, PNAS, 105(39), 14855-14860, 2008.

About the Speaker: Dr. Yuhai Tu graduated from USTC in 1987, when he went to the US under the CUSPEA program. He received his Ph. D in Theoretical Physics from UC, San Diego in 1991. He was a Division Prize Fellow at Caltech from ‘91-‘94. He joined IBM Watson Research Center as a permanent Research Staff Member in 1994 and became head of the theory group in 2003. He has broad research interests, including nonequilibrium statistical physics, critical phenomena, nonlinear dynamics, pattern formation, surface physics, and most recently computational biology. He has published over 80 papers in these areas, many in top journals such as PRL, PNAS, MSB, and Nature Physics (H-index=32). He was elected an APS Fellow in 2004 for “outstanding discoveries in statistical physics, such as a novel broken-symmetry phase in two-dimensional systems, and novel applications of statistical physics to problems in computational biology”. He serves on the IBM Blue-Gene supercomputer policy board, and he holds a ChangJiang visiting chair professorship at Peking University (PKU).

Date&Time: August 16, 2012 (Thursday) 10:00-11:00a.m.
Location: 606 Conference Room, No.3 Heqing Road, Haidian District