Project description:Ectoderm-derived neural crest is a transient structure arising during early embryogenesis in vertebrates. Neural crest consists of four derivatives based on their anterior- to posterior location along the body axis; cranial, vagal, trunk and sacral, respectively. We recently showed that trunk neural crest-specific gene MOXD1 functions as a tumor suppressor in trunk neural crest-derived childhood cancer form neuroblastoma and is essential for proper development of healthy adrenal glands. However, the role of MOXD1 during early embryogenesis is not known. Here, we conditionally knocked out MOXD1 in trunk neural crest cells before they become lineage-committed, using a CRISPR/Cas9 approach in chick embryos. Assessment of embryo growth showed that knockout of MOXD1 delayed development with knockout embryos being smaller. RNA sequencing of trunk-derived neural crest cells from control and knockout embryos showed enrichment of genes connected to gland development, copper ion metabolism and neuroblastoma progression. In conclusion, MOXD1 is important during early and prolonged embryonic development with effects on gland formation, possibly mediated via its role in copper metabolism.
Project description:Neural crest cells migrate extensively in vertebrate embryos to populate diverse derivatives including ganglia of the peripheral nervous system. Little is known about the molecular mechanisms that tell migrating trunk neural crest cells to settle at selected sites in the embryo by ceasing migration and initiating differentiation programs.
Project description:Skin-derived precursors (SKPs) are multipotent dermal stem cells that reside within a hair follicle niche and that share properties with embryonic neural crest precursors. Here, we have asked whether SKPs and their endogenous dermal precursors originate from the neural crest or whether, like the dermis itself, they originate from multiple developmental origins. To do this, we used two different mouse Cre lines that allow us to perform lineage tracing: Wnt1-cre, which targets cells deriving from the neural crest, and Myf5-cre, which targets cells of a somite origin. By crossing these Cre lines to reporter mice, we show that the endogenous follicle-associated dermal precursors in the face derive from the neural crest, and those in the dorsal trunk derive from the somites, as do the SKPs they generate. In spite of these different developmental origins, SKPs from these two locations are functionally similar, even with regard to their ability to differentiate into Schwann cells, a cell type only thought to be generated from the neural crest. Analysis of global gene expression using microarrays confirmed that facial and dorsal SKPs exhibit a very high degree of similarity, and that they are also very similar to SKPs derived from ventral dermis, which has a lateral plate origin. However, these developmentally-distinct SKPs also retain differential expression of a small number of genes that reflect their developmental origins. Thus, an adult neural crest-like dermal precursor can be generated from a non-neural crest origin, a finding with broad implications for the many neuroendocrine cells in the body. We obtained three independent isolates each of dorsal trunk SKPs, ventral trunk SKPs and facial SKPs and four isolates of MSCs, all generated from adult rats. RNA samples deriving from these cells were analyzed on the Affymetrix GeneChip Rat Gene 1.0 ST Array.
Project description:The dynamics of multipotent neural crest cell differentiation and invasion as cells travel throughout the vertebrate embryo remain unclear. Here, we preserve spatial information to derive the transcriptional states of migrating neural crest cells and the cellular landscape of the first four chick cranial to cardiac branchial arches (BA1-4) using label-free, unsorted single-cell RNA sequencing. The faithful capture of branchial arch-specific genes led to identification of novel markers of migrating neural crest cells and 266 invasion genes common to all BA1-4 streams. Perturbation analysis of a small subset of invasion genes and time-lapse imaging identified their functional role to regulate neural crest cell behaviors. Comparison of the neural crest invasion signature to other cell invasion phenomena revealed a shared set of 45 genes, a subset of which showed direct relevance to human neuroblastoma cell lines analyzed after exposure to the in vivo chick embryonic neural crest microenvironment. Our data define an important spatio-temporal reference resource to address patterning of the vertebrate head and neck, and previously AQ1 unidentified cell invasion genes with the potential for broad impact.
Project description:We employ RNA-seq of FACS sorted cell populations to identify genes that are enriched in cranial neural crest in relationship to the trunk. Transcriptional profiling of delaminating cranial and trunk neural crest subpopulations.
Project description:To elucidate the molecular features of craniofacial versus trunk neural crest cells (NCCs), we utilized P0-Cre/Floxed-EGFP mice that specifically label NCCs (Yamauchi et al., 1999 (PMID 10419695)). Craniofacial and trunk regions were isolated from P0-Cre/Floxed-EGFP mouse embryos at embryonic day E12.5, and dissociated cells were analyzed by flow cytometory in regard to the intensity of EGFP. In this study, we performed at least duplicate experiments for each of the four groups (Craniofacial EGFP+, Trunk EGFP+, Craniofacial EGFP-, Trunk EGFP-). Total of 9 samples.
Project description:Neural crest cells are multipotent cells that delaminate from the neuroepithelium, migrating throughout the embryo. Aberrant migration causes developmental defects. Animal models are improving our understanding of neural crest anomalies, but in vivo migration behaviours are poorly understood. Here, we demonstrate that murine neural crest cells display actin-based lamellipodia and filopodia in vivo. Using neural crest-specific knockouts or inhibitors, we show that the serine-threonine kinase Glycogen Synthase Kinase-3 (GSK3), and the cytoskeletal regulator Lamellipodin (Lpd), are required for lamellipodia formation whilst preventing focal adhesion maturation. Lpd is a novel substrate of GSK3 and phosphorylation of Lpd favours interactions with the Scar/WAVE complex (lamellipodia formation) at the expense of VASP and Mena interactions (adhesion maturation and filopodia formation). This improved understanding of cytoskeletal regulation in mammalian neural crest migration has general implications for neural crest anomalies and cancer.
Project description:Neural crest cells are both highly migratory and significant to vertebrate organogenesis. However, the signals that regulate neural crest cell migration remain unclear. Here, we test the function of DAN, a BMP antagonist we detected by analysis of chick cranial mesoderm. Our analysis shows that, prior to neural crest cell exit from the hindbrain, DAN is expressed in the mesoderm, then it becomes absent along cell migratory pathways. Cranial neural crest and metastatic melanoma cells avoid DAN protein stripes in vitro. Addition of DAN reduces the speed of migrating cells, in vivo and in vitro respectively. In vivo loss-of-function of DAN results in enhanced neural crest cell migration by increasing speed and directionality. Computer model simulations support the hypothesis that DAN restrains cell migration by regulating cell speed. Taken together, our results identify DAN as a novel factor that inhibits uncontrolled neural crest and metastatic melanoma invasion and promotes collective migration in a manner consistent with inhibition of BMP signaling.