Background: Neural crest cells (NCCs) delaminate from the neural tube (NT) and migrate ventrally to generate the trunk peripheral nervous system (PNS). Although several signaling pathways have been identified that steer NCCs once they are on their ventral trajectory, no molecules have been identified that are required for the initial migration between the NT and the dorsal root ganglion. Given the critical role of fibroblast growth factor (FGF) signaling in embryogenesis, we investigated its function in this initial migration.

Results: FGFR1 signaling is required for the migration of newly delaminated NCCs onto the ventral pathway. Live imaging of migrating NCCs revealed that inhibition of FGFR1 signaling caused the dorsally stalled NCCs to lose their dorsal/ventral oriented polarity and instead adopt a rounded morphology while dynamically extending filopodia. FGF8, an FGFR1 ligand, increased motility of NCCs away from the NT by acting chemokinetically. Finally, we provide evidence that inhibition of FGFR1-mediated chemokinesis is partially rescued by increasing Akt signaling, inhibiting RhoA, and activation of N-cadherin signaling.

Conclusion: These data support a model in which NCCs are stimulated chemokinetically by FGF:FGFR1 signaling, and that this activation positions and orients NCCs on their ventral migratory route-a process that is essential for patterning the trunk PNS.

Download full-text PDF

Source
http://dx.doi.org/10.1002/dvdy.190DOI Listing

Publication Analysis

Top Keywords

nccs ventral
12
fgf signaling
8
signaling required
8
neural crest
8
crest cells
8
nccs
8
fgfr1 signaling
8
signaling
6
required chemokinesis
4
ventral
4

Similar Publications

A central question in biology is the molecular origins of phenotypic diversity. While genetic changes are key to the genotype-phenotype relationship, alterations to chromatin structure and the physical packaging of histone proteins may also be important drivers of vertebrate divergence. We investigate the impact of such an epigenetic mechanism, histone acetylation, within a textbook example of an adaptive radiation.

View Article and Find Full Text PDF

Craniofacial and cardiac defects in zebrafish mutants mimic CHARGE syndrome.

Front Cell Dev Biol

December 2022

Saban Research Institute and Heart Institute, Children's Hospital Los Angeles, Los Angeles, CA, United States.

Congenital heart defects occur in almost 80% of patients with CHARGE syndrome, a sporadically occurring disease causing craniofacial and other abnormalities due to mutations in the gene. Animal models have been generated to mimic CHARGE syndrome; however, heart defects are not extensively described in zebrafish disease models of CHARGE using morpholino injections or genetic mutants. Here, we describe the co-occurrence of craniofacial abnormalities and heart defects in zebrafish mutants.

View Article and Find Full Text PDF

Hyaluronan (HA) is a major extracellular matrix component whose tissue levels are dynamically regulated during embryonic development. Although the synthesis of HA has been shown to exert a substantial influence on embryonic morphogenesis, the functional importance of the catabolic aspect of HA turnover is poorly understood. Here, we demonstrate that the transmembrane hyaluronidase TMEM2 plays an essential role in neural crest development and the morphogenesis of neural crest derivatives, as evidenced by the presence of severe craniofacial abnormalities in Wnt1-Cre-mediated Tmem2 knockout (Tmem2CKO) mice.

View Article and Find Full Text PDF

Waardenburg syndrome type 4 (WS4) combines abnormal development of neural crest cell (NCC)-derived melanocytes (causing depigmentation and inner ear dysfunction) and enteric nervous system (causing aganglionic megacolon). The full spectrum of WS4 phenotype is present in Spot mice, in which an insertional mutation close to a silencer element leads to NCC-specific upregulation of the transcription factor-coding gene Nr2f1. These mice were previously found to develop aganglionic megacolon because of NR2F1-induced premature differentiation of enteric neural progenitors into enteric glia.

View Article and Find Full Text PDF

Mutations in allele are implicated in multiple brain tumors, indicating a rigorous control of Rac1 activity is required for neural tissue normal development and homeostasis. To understand how elevated Rac1 activity affects neural crest cells (NCCs) development, we have generated mice, in which a constitutively active Rac1 mutant is expressed specifically in NCCs derivatives. Our results revealed that augmented Rac1 activity leads to enlarged midbrain and altered cell density, accompanied by increased NCCs proliferation rate and misrouted cell migration.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!