Project description:Neural crest cells are migratory progenitor cells that contribute to nearly all tissues and organs throughout the body. Their formation, migration and differentiation are regulated by a multitude of signaling pathways, that when disrupted can lead to disorders termed neurocristopathies. While work in avian and amphibian species has revealed essential factors governing the specification and induction of neural crest cells during gastrulation and neurulation in non-mammalian species, their functions do not appear to be conserved in mice, leaving major gaps in our understanding of neural crest cell formation in mammals. Here we describe Germ Cell Nuclear Factor (GCNF/Nr6a1), an orphan nuclear receptor, as a critical regulator of neural crest cell formation in mice. Gcnf null mutant mice, exhibit a major disruption of neural crest cell formation. The purpose of this experiment is to examine gene expression changes in response to Gcnf mutation in anterior and posterior cranial regions of E9.25 mouse embryos.
Project description:Gastruloids are a powerful in vitro model of early human development. However, although elongated and composed of all three germ layers, human gastruloids do not morphologically resemble post-implantation human embryos. Here we show that an early pulse of retinoic acid (RA), together with later Matrigel, robustly induces human gastruloids with posterior embryo-like morphological structures, including a neural tube flanked by segmented somites, and diverse cell types including neural crest, neural progenitors, renal progenitors, and myocytes. Through in silico staging based on single-cell RNA-seq (scRNA-seq), we find that human RA-gastruloids progress further than other human or mouse embryo models, aligning to E9.5 mouse and CS11 cynomolgus monkey embryos. We leverage chemical and genetic perturbations of RA-gastruloids to confirm that WNT and BMP signalling regulate somite formation and neural tube length in the human context, while transcription factors TBX6 and PAX3 underpin presomitic mesoderm and neural crest, respectively. Looking forward, RA-gastruloids are a robust, scalable model for decoding early human embryogenesis.
Project description:Background: Spina bifida is one of the most common and life threatening human congenital defects. Despite considerable effort and investigations, the causes and mechanisms underlying this malformation remain poorly characterized. In order to better understand pathogenesis of this abnormality, we conducted a microarray study to compare gene expression profiles between two mouse models, CLX-Splotch and Fkbp8Gt(neo), that both have spina bifida. Results: To compare the gene expression profiles in these two mouse models we performed microarray analysis using Mouse Whole Genome CodeLink Bioarray. We compared the level of gene expression between wildtype and homozygous mutant embryos in Fkbp8Gt(neo) and CXL-Splotch separately. A total of 54 genes were determined to be differentially expressed (25 down, 29 up) in the posterior neural tube of Fkbp8Gt(neo) mice embryos; while 73 genes were differentially expressed (56 down, 17 up) in the CXL-Splotch mouse. The only two genes that showed decreased expression in both mutants were v-ski sarcoma viral oncogene homolog (Ski) and Zic1, a transcription factor member of the zinc finger family. Interestingly, when Gene Ontology (GO) analysis was performed on all of the differentially expressed genes, there was a striking enrichment of genes associated with mesoderm development and central nervous system development in CLX-Splotch, whereas in Fkbp8Gt(neo) genes involved in dorsal/ventral pattern formation, cell fate specification, and positive regulation of cell differentiation were distinguished. This SuperSeries is composed of the following subset Series: GSE25974: Gene expression-based analysis of neural tube closure for the posterior neuropore of Fkbp8 embryos at E9.5 GSE25975: Gene expression-based analysis of neural tube closure for the posterior neuropore of Splotch embryos at E9.5
Project description:Neural crest cells are migratory progenitor cells that contribute to nearly all tissues and organs throughout the body. Their formation, migration and differentiation are regulated by a multitude of signaling pathways, that when disrupted can lead to disorders termed neurocristopathies. While work in avian and amphibian species has revealed essential factors governing the specification and induction of neural crest cells during gastrulation and neurulation in non-mammalian species, their functions do not appear to be conserved in mice, leaving major gaps in our understanding of neural crest cell formation in mammals. Here we describe Germ Cell Nuclear Factor (GCNF/Nr6a1), an orphan nuclear receptor, as a critical regulator of neural crest cell formation in mice. Gcnf null mutant mice, exhibit a major disruption of neural crest cell formation. The purpose of this experiment is to examine gene expression changes in response to Gcnf mutation in E9.0 mouse embryos.