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Villaronga Luque, A.

Publications and source records attributed to Villaronga Luque, A..

2 recordsLinked to original sources

Integrated Molecular-Phenotypic Profiling Reveals Metabolic Control of Morphological Variation in Stembryos

Mammalian stem-cell-based models of embryo development (stembryos) hold great promise in basic and applied research. However, considerable phenotypic variation despite identical culture conditions limits their potential. The biological processes underlying this seemingly stochastic variation are poorly understood. Here, we investigate the roots of this phenotypic variation by intersecting transcriptomic states and morphological history of individual stembryos across stages modeling post-implantation and early organogenesis. Through machine learning and integration of time-resolved single-cell RNA-sequencing with imaging-based quantitative phenotypic profiling, we identify early features predictive of the phenotypic end-state. Leveraging this predictive power revealed that early imbalance of oxidative phosphorylation and glycolysis results in aberrant morphology and a neural lineage bias that can be corrected by metabolic interventions. Collectively, our work establishes divergent metabolic states as drivers of phenotypic variation, and offers a broadly applicable framework to chart and predict phenotypic variation in organoid systems. The strategy can be leveraged to identify and control underlying biological processes, ultimately increasing the reproducibility of in vitro systems. HighlightsO_LITime-resolved single-cell RNA-sequencing and imaging-based quantitative charting of hundreds of individual stembryos generates molecular and phenotypic fingerprints C_LIO_LIMachine learning and integration of molecular and phenotypic fingerprints identifies features and biological processes predictive of phenotypic end-state C_LIO_LIEarly imbalance of oxidative phosphorylation and glycolysis results in aberrant morphology and cellular composition C_LIO_LIMetabolic interventions tune stembryo end-state and can correct derailment of differentiation outcomes C_LI

developmental biology↗

Genome-wide identification of notochord enhancers comprising the regulatory landscape of the Brachyury (T) locus in mouse

The node and notochord are important signaling centers organizing dorso-ventral patterning of cells arising from neuro-mesodermal progenitors forming the embryonic body anlage. Due to the scarcity of notochordal progenitors and notochord cells, a comprehensive identification of regulatory elements driving notochord-specific gene expression has been lacking. Here we have used ATAC-seq analysis of FACS-purified notochordal cells from TS12-13 mouse embryos to identify 8921 putative notochord enhancers. In addition, we established a new model for generating notochordal cells in culture, and found 3728 of these enhancers occupied by the essential notochordal regulators Brachyury (T) and/or Foxa2. We describe the regulatory landscape of the T locus comprising 10 putative enhancers occupied by these factors and confirmed the regulatory activity of 3 of these elements. Moreover, we characterized one new notochord enhancer, termed TNE2, in embryos. TNE2 complements the loss of TNE in the trunk notochord, and is essential for notochordal cell proliferation and differentiation in the tail. Our data demonstrate the essential role of Foxa2 in switching T expressing cells from a NMP/mesodermal trajectory to the notochordal fate. Summary statementCombining multi-omics assays of purified embryonic and in vitro generated cells we identified thousands of notochord enhancers comprising TNE2 essential for T expression and tail development of the mouse embryo.

developmental biology↗