CDB Seminar - Adam C Martin, MIT

Abstract: Throughout the lifespan of an organism, tissues are remodeled to shape organs and organisms and to maintain tissue integrity and homeostasis.  Apical constriction is a ubiquitous cell shape change of epithelial tissues that promotes epithelia folding and cell/tissue invagination in a variety of contexts.  Apical constriction promotes tissue bending by changing the shape of constituent cells from a columnar-shape to a wedge-shape.  Drosophila gastrulation is one of the classic examples of apical constriction, where cells constrict to fold the primitive epithelial sheet and internalize cells that will give rise to internal organs.  We have used a combination of imaging, experimental perturbation, and modeling, to determine how actomyosin organization promotes tissue folding.  The actin cytoskeleton is organized in both time and space to facilitate apical constriction.  We found that actomyosin contraction is pulsatile and requires dynamic regulation of upstream signaling processes.  In addition, we found that actin and myosin are differentially patterned across tissues, which can lead to regionalized cell behaviors that promote proper shape formation.  Our findings have advanced our understanding of how tissue shape emerges from actomyosin patterning across different length scales.

Suggested references: 

1)Jodoin, J.N., J.S. Coravos, S. Chanet, C.G. Vasquez, M. Tworoger, E.R. Kingston, L.A. Perkins, N. Perrimon, and A.C. Martin. 2015. Stable Force Balance between Epithelial Cells Arises from F-Actin Turnover. Dev Cell. 35:685-697.

2)Yevick, H.G., Miller, P.W., Dunkel, J., and Martin, A.C., 2019. Structural Redundancy in Supracellular Actomyosin Networks Enables Robust Tissue Folding. Dev Cell. 50:586-598.

3)Imran Alsous J, Romeo N, Jackson JA, Mason FM, Dunkel J^^, Martin AC^^. Dynamics of hydraulic and contractile wave-mediated fluid transport during Drosophila oogenesis. Proc. Nat. Acad. Sci., 2021:118(10):e2019749118. ^^ Joint corresponding authors

Host: Roberto Mayor

Join Zoom Meeting: https://ucl.zoom.us/j/98006944701?pwd=amNOSHkwNVlLY3cxcW9TWXV3aytLQT09

Meeting ID: 980 0694 4701 / Passcode: 589699