QUANTITATIVE LIFE SCIENCES GUEST SEMINAR - 6 May

[Quantitative Life Sciences]

QUANTITATIVE LIFE SCIENCES GUEST SEMINAR

Friday, 6 May at 11:30

ICTP, Central Area, 2nd floor, old SISSA building

Speaker: Matteo Osella - BioPhys - Computational Biology Group, 
University of Turin, Italy

Title: "Cell Division Control in E. coli"

Abstract:
The coordination of cell growth and division is a long-standing problem 
in biology. In particular, the mechanisms that ensure size homeostasis 
and, at the same time, adapt cell growth and size to the environment 
have been the subject of intense research. However, the answers were 
traditionally hindered by limited statistics on single cells. 
Contemporary experimental techniques overcome this problem, but this 
progress must be combined with new theoretical tools to approach the 
data. Focusing on E. coli, we introduced a quantitative method for 
estimating the variables controlling the division rate from dynamic 
data, and used it to build a minimal stochastic model of cell growth and 
division. Combining this method with large-scale microscopy experiments, 
classic quantitative laws relating cell size, doubling time and growth 
rate of bacterial populations in different nutrient conditions can be 
revisited at the single cell level. The main result is the emergence of 
a combination of universality and individuality in the growth-division 
laws of single E. coli cells. These two apparently contrasting behaviors 
emerge naturally from the condition-dependent modulation of the division 
control mechanism, thus actually representing two sides of the same 
coin. Finally, the simultaneous observation of cell growth and DNA 
replication dynamics allowed us to pinpoint replication initiation and 
cell division as the two main "checkpoints" for size control. This opens 
the way to more detailed models of the process, and to rigorous tests of 
molecular cell-cycle descriptions.

Web page: http://indico.ictp.it/event/7867/

-- 
Erica Sarnataro
Group Secretary
Quantitative Life Sciences
The Abdus Salam International Centre for Theoretical Physics (ICTP)
Trieste,  Italy
Tel. +39-040-2240623
e-mail:qls at ictp.it