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:We report that cancer associated protein HIF-2a is expressed in trunk neural crest neuroblastoma precursor cells in the developing embryo in three different species; human, mouse and avian. Dysregulation of HIF-2a leads to alterations in embryonic development, and neural crest cell migration, proliferation and self-renewal capacity. With RNAsequencing we report that alterations of HIF-2a expression affects the global transcriptome and that gene ontology enrich for the same processes observed in vivo.
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: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:Bone is an evolutionary novelty of vertebrates, likely to have first emerged as part of ancestral dermal armor that consisted of osteogenic and odontogenic components. Whether these early vertebrate structures arose from mesoderm or neural crest cells has been a matter of considerable debate. To examine the developmental origin of the bony part of the dermal armor, we have performed in vivo lineage tracing in the sterlet sturgeon, a representative of non-teleost ray-finned fish that has retained an extensive postcranial dermal skeleton. The results definitively show that sterlet trunk neural crest cells give rise to osteoblasts of the scutes. Transcriptional profiling further reveals neural crest gene signature in sterlet scutes as well as bichir scales. Finally, histological and microCT analysis of ray-finned fish dermal armor show that their scales and scutes are formed by bone, dentin and hypermineralized covering tissues, in various combinations, that resemble those of the first armored vertebrates. Taken together, our results support a primitive skeletogenic role for the neural crest along the entire body axis, that was later progressively restricted to the cranial region during vertebrate evolution. Thus, the neural crest was a crucial evolutionary innovation driving the origin and diversification of dermal armor along the entire body axis.
Project description:The in vitro generation of neural crest (NC) cells from human pluripotent stem cells (hPSCs) is a valuable approach to study human NC biology and isolate NC derivatives for disease modelling/regenerative medicine applications. However, conventional differentiation protocols induce only a modest yield of NC cells corresponding to the trunk level. Here we show that trunk NC cells and, their downstream derivatives, sympathoadrenal progenitors, can be produced at a high efficiency from hPSC-derived axial progenitors, the in vitro counterparts of the posteriorly-located drivers of embryonic axis elongation. Moreover, using transcriptome analysis, we define the molecular signatures associated with the emergence of human NC cells of distinct axial identities. Collectively, our findings indicate that a post-cranial NC state is achieved through two different routes: the birth of cardiac and vagal NC is facilitated by retinoic acid-induced posteriorisation of an anterior precursor whereas a trunk fate relies on a posterior axial progenitor intermediate.