Plenary 6.3

9/2 4:00 - 6:00, Memorial Auditorium

Protein localization is important for bacterial cell-cycle regulation?

Kerwyn C. Huang

Assistant Professor of Bioengineering, Stanford University.

In this talk, I will describe how pole-to-pole oscillations of the Min-protein system help to regulate cell division in E. coli. We have developed a model of the Min system which accurately reproduces the observed oscillations in rod-shaped, round, and branched cells. These results suggest that oscillations may provide a general mechanism by which proteins can localize in response to features of cell geometry. As a counterpoint to the importance of spatial localization in the Min system, I will also present evidence that misclocalization of the cell-cycle control system in Caulobacter crescentus can be corrected for by overexpression, suggesting that localization may have evolved via selection for efficiency.

Kerwyn C. HuangOur laboratory is interested in the relationships among cell shape detection, determination, and maintenance in bacteria. Cell shape plays a critical role in regulating many physiological functions, yet little is known about how shape is determined and maintained. Inside the cell, many proteins organize, but how they detect and respond to the cellular morphology is also largely mysterious. We are integrating computational physics-based models with evolutionary and synthetic biology approaches to control morphogenesis and cellular organization. Current topics of interest are (i) cell-wall growth, (ii) spatial mechanisms of cell-cycle control, (iii) division, (iv) membrane organization, (v) mechanosensitivity, and (vi) phototaxis.