9.45-10.00 Laura Caetano, University of Southampton, UK
“Mouse blastocysts sense maternal nutrition quality via isoleucine availability to regulate trophectoderm endocytosis level, a survival mechanism”
Poor maternal nutrition around mouse conception is sensed by early embryos which adapt their development to protect offspring survival. One compensation is increased endocytosis of nutritive uterine fluid by blastocyst trophectoderm, a stress response linked with later-life disease. My work identifies deficient amino acids, especially depleted isoleucine, activates this response. Low Isoleucine promotes nuclear delivery of transcriptor factor EB (TFEB) in an mTORC1-dependent process resulting in enhanced endocytosis and lysosomal volume per cell, activated at morula-blastocyst transition.
10.00-10.15 Hugo Silva, Life and Health Sciences Research Institute (ICVS), Braga, Portugal
“A glycolytic lactate-based metabolism underlies chicken lung branching morphogenesis”
Lung branching morphogenesis is an intricate process governed by mesenchymal-epithelial interactions and dependent on a complex signaling. To sustain high proliferative rates, free energy and building blocks are necessary. The metabolic requirements of the embryonic lung are unknown, thus we characterized the metabolic profile of early chick lung branching. Ex vivo explant culture, 1H-NMR, qPCR, in situ hybridization and western blot were performed. Results revealed lactate and acetate as developmental biomarkers, and branching morphogenesis showed a glycolytic lactate-dependent metabolism.
10.15-10.30 Marta Shahbazi, University of Cambridge, UK
“Defining pluripotency in 3D: from embryonic stem cell identity to morphogenesis”
Pluripotency refers to the capability of a cell to generate all the cell types of the organism. Different pluripotent states are identified in vivo and in vitro, but their biological significance with respect to morphogenesis remains unclear.We show that exit from an unrestricted naïve state directs epithelialization in ESCs and embryos. This process is controlled by Oct4, which mediates expression of sialomucins, required for lumen opening. Naïve cells polarize but fail to open a lumen. Likewise, mouse and human embryos locked in the naïve state fail to form the amniotic cavity.
10.30-10.45 Akanksha Jain, Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
“A linked chain of autonomously contracting cells forms an actomyosin cable during serosa window closure in the beetle Tribolium castaneum”
Extraembryonic tissues in insects show diverse morphologies. We characterized cellular and actomyosin dynamics in Tribolium castaneum embryos using multiview lightsheet microscopy and unfold our 4D data into 3D cartographic maps. Using this we observed a contractile actomyosin cable that forms during serosa window closure. It is formed as a shifting boundary of autonomously contractile cells which intercalate into the serosa contributing to its area. Our results report a novel actomyosin cable type that could show conserved cellular dynamics across insects which undergo serosa window closure.