Physical principles of cell polarization: From symmetry breaking to fate specification 

Through their ability to link cell architecture and signaling networks, cell polarity networks play fundamental roles in the spatial regulation of intracellular processes and in so doing drive processes as diverse as cell migration, establishment of body axis, cell fate specification, and the development of tissues and organisms.  Over the past decade, there has been a transition from genetic analysis from identification of molecules and interactions to systems-level approaches as the dynamic and complex nature of polarity networks has become apparent. Our lab focusses on a conserved polarity network in animal cells defined by the PAR (PAR-titioning defective) proteins.  As cells polarize, PAR proteins ‘pattern’ the cell membrane into domains that define a cell’s functional asymmetry, serving as spatial regulators of downstream pathways, such as spindle positioning, segregation of fate determinants, and membrane trafficking. Using the C. elegans embryo as a model system, we combine genetics, quantitative imaging and mathematical modeling to uncover the design principles of the PAR network that enable intracellular patterning of cells, to determine how these principles emerge from individual and collective properties of the component molecules, and understand the consequences of these principles as they play out over embryonic development. 

Host: Prof Andrew Goryachev