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.