The very fast development of live cell imaging, image processing and high throughput single cell sequencing have generated a wealth of data regarding the behaviour of individual cells. Yet, how those single cell parameters influence the behaviour at the population or at the organ levels are still not well understood. As such an important challenge of quantitative biology is to connect these two scales by linking the diversity of single cell behaviours to the emergent properties at the population and tissue levels.

In this symposium, we wish to provide a platform for discussing the relevant types of study and the variety of approaches that can help connect those two scales, for example by studying intermediate scales of a few cells to a few thousand cells. We will focus on common questions/parameters that are relevant for a wide range of biological systems, including population dynamics in bacteria or tumours, stem cell fate specification, or morphogenesis. Similar questions emerge in all of these different biological systems: can new properties emerge without interactions? Which properties emerge from local interactions versus a centralised control? What is the contribution of noise?

The day will be organized in 4 sessions where speakers will address similar biological questions (regulation of tissue/population size, fate specification, emergence of resistance, morphogenesis) in different systems (including experiments and theory).The day will finish with an open 30-40 min open discussion in order to summarise potential common features, open questions and perspectives.

Registration is free but mandatory. There will also be some spots available for poster presentation. If you want to present a poster, please send your title and abstract by e-mail to: romain.levayer@pasteur.fr and charles.baroud@pasteur.fr with the subject "Bridging the scales"

Program

9:00-9:15 am

Introduction

9:15-9:45 am

Grégory Batt: Balancing a genetic toggle switch by real-time control and periodic stimulations

9:45-10:15 am

Jordi Garcia-Ojalvo: Growth dynamics of mixed-species bacterial populations

10:15-10:45 am

Sylvie Méléard: Stochastic Modeling of the growth of Escherichia coli

10:45-11:15 am

Coffee break

11:15-11:45 am

Laure Bally-Cuif: Population mechanisms controlling adult stem cell activation

11:45-12:15 am

François Schweisguth: Self-organisation and patterning dynamics in Drosophila

12:15-12:45 pm

Nathalie Sauvonnet: A bioengineered human Organ-on-Chip reveals that mechanical forces and 3D microenvironment of the intestinal epithelium are critical for Shigella infection

12:45-2:00 pm

Lunch break and poster session

2:00-2:30 pm

Jean Clairambault: Modelling plasticity of cancer cells and emergence of drug-induced drug resistance using adaptive cell population dynamics

2:30-3:00 pm

Dagmar Iber: From Networks to Function – Computational Models of Organogenesis

3:00-3:30 pm

Giovanni Cappello: Is extracellular matrix a pressure sensor?

3:30-4:00 pm

Coffee break

4:00-4:30 pm

Francis Corson: Mechanics of gastrulation

4:30-5:00 pm

Nicolas Desprat: The spatial organization of bacterial interactions: from secreted adhesins to secreted goods

5:00-5:30 pm

Arezki Boudaoud: Heterogeneity and robustness in morphogenesis

5:30-6:00 pm

François Graner: From cell dynamics to epithelial tissue patterning : a multiscale analysis

6:00-6:30 pm

Final discussion

6:30-8:00 pm

Poster session and beers