Laurent Jutras Dubé

Graduate Student
McGill Univ
Email author

Geometric models for robust encoding of dynamical information into embryonic patterns

Laurent Jutras-Dubé, Ezzat El-Sherif, Paul François

 

Hello!

I'm Laurent, a Ph.D. student in the Department of Physics at McGill University, under the supervision of Prof. Paul François. I graduated from the University of Montreal in Mathematics and Physics in 2016. My main research field of interest is theoretical biophysics, and more precisely pattern formation during embryo development. My goal is to further our understanding of the process by which cells determine their position within the embryo, so that they can become the right type of cell at the right moment.

For my research project, I focus on the formation of the somites, which are the precursors of the vertebrae. Each somite is divided into an anterior and a posterior compartment. Two main theoretical approaches are currently used to model how cells determine if they are in the anterior or the posterior compartment of a somite. I built a mathematical model that encompasses these two approaches, and I use numerical simulations and bifurcation analysis to assess their robustness to different types of perturbations, including noise and parameter changes. I found that one approach is consistently more robust, and is in better agreement with the latest experimental observations relevant to somite formation.

If you are interested in learning about my research project in more details, please pass by my poster... virtually! You can click on the Webex link button below, or send me an email by clicking on the Email author button. I look forward to answering your questions and discussing science with you on Monday, August 10 from 3:30 to 4:45 PM. Note that you do not have to download the Webex desktop application to join the meeting: you can simply click on "Join from your browser".

To view my poster, please click on the 'Presentation' button below.

 

Geometric models for robust encoding of dynamical information into embryonic patterns

Laurent Jutras-Dubé, Ezzat El-Sherif, Paul François
Abstract

During development, cells gradually assume specialized fates via changes of transcriptional dynamics, sometimes even within the same developmental stage. For anterior-posterior patterning in metazoans, it has been suggested that the gradual transition from a dynamic genetic regime to a static one is encoded by different transcriptional modules. In that case, the static regime has an essential role in pattern formation in addition to its maintenance function. In this work, we introduce a geometric approach to study such transition. We exhibit two types of genetic regime transitions, respectively arising through local or global bifurcations. We find that the global bifurcation type is more generic, more robust, and better preserves dynamical information. This could parsimoniously explain common features of metazoan segmentation, such as changes of periods leading to waves of gene expressions, “speed/frequency-gradient” dynamics, and changes of wave patterns. Geometric approaches appear as possible alternatives to gene regulatory networks to understand development.