Tuesday, 26 March 2019 at 15:00 | Large Operon, EMBL Heidelberg
Eric Siggia | The Rockefeller University (US)
Host: Pierre Neveu, Cell Biology and Biophysics Unit
Exploring embryonic patterning with colonies of human embryonic stem cells.
The embryo evolved to make a fetus and thus multiple modes of regulation conspire to ensure a robust outcome. This makes the task of quantifying the pathways defining the mammalian embryo particularly difficult. Embryonic stem cells (ESC) give rise to all cells of the body proper. We have shown several years ago, how merely confining human ESC to two dimensional patterns, causes the cells to recapitulate the spatial patterning seen in the mouse embryo at the onset of gastrulation. We have dissected the cascade of secreted factors and the location of receptors driven by apical-basal polarity responsible for the patterns. A prediction for how morphogens are targeted in the mouse was recently confirmed by another group. Our assay can be extended to three dimensions and the model epiblast shown to spontaneously break symmetry and form a primitive streak. A second layer of extraembryonic like cells adds additional realism and new interactions. Synthetic systems allow one to peal back the layers of regulation that make embryonic development so robust. They are easy to manipulate and suggest targeted experiments to pursue in-vivo.
Eric Siggia was trained in physics and pursued a variety of problems in phase transitions, statistical mechanics, quantum spin systems, fluid mechanics and chaos while at Cornell University. After moving to Rockefeller in the late 1990’s he worked on protein trafficking with Lippincott-Schwartz, polymer physics of DNA and chromosomes, bioinformatics of gene regulation, the cell cycle in yeast with single cell assays and microfluidics, antibiotic resistance in Staph Aureus, and in the last decade, development in the worm and mammals with the aid of stem cell technologies combined with biophysical methods.