IAM – PIMS Distinguished Colloquium: Stas Shvartsman

I will present the results of our recent work on epithelial morphogenesis, a highly conserved set of processes that transform two-dimensional sheets of cells into complex three-dimensional structures. Such transformations play key roles during embryogenesis and their understanding is important both from a purely scientific standpoint and for the design of man-made tissues and organs. Our laboratory is using the eggshell morphogenesis in the fruit fly Drosophila melanogaster as a model for studying epithelial morphogenesis in a relatively simple setting, with a constant number of cells. Based on the combination of time lapse imaging studies and three-dimensional image reconstructions we found that epithelial morphogenesis in this system can be viewed as a two-stage process, in which buckling of a group of cells out of a curved sheet is followed by ordered cell rearrangements, generating a tube-like structure. A small number of cells involved in this transformation (<100) and their reproducible dynamics enable its computational modeling. I will present models based on vertex description of cell sheets and discuss some applied mathematical problems that arise in the analysis of these models.

References:

Osterfield M, Du X, Schüpbach T, Wieschaus E, Shvartsman SY. Three-dimensional epithelial morphogenesis in the developing Drosophila egg. Dev Cell. 2013 Feb 25;24(4):400-10.

Fletcher AG, Osterfield M, Baker RE, Shvartsman SY. Vertex models of epithelial morphogenesis. Biophys J. 2014 Jun 3;106(11):2291-304.

Osterfield M, Schüpbach T, Wieschaus E, Shvartsman SY. Diversity of epithelial morphogenesis during eggshell formation in drosophilids. Development. 2015 Jun 1;142(11):1971-7.