title: Dynamic and differential regulation of stem cell factor FoxD3 in the neural crest is Encrypted in the genome.
abstract: The critical stem cell transcription factor FoxD3 is expressed by the premigratory and migrating neural crest, an embryonic stem cell population that forms diverse derivatives. Despite its important role in development and stem cell biology, little is known about what mediates FoxD3 activity in these cells. We have uncovered two FoxD3 enhancers, NC1 and NC2, that drive reporter expression in spatially and temporally distinct manners. Whereas NC1 activity recapitulates initial FoxD3 expression in the cranial neural crest, NC2 activity recapitulates initial FoxD3 expression at vagal/trunk levels while appearing only later in migrating cranial crest. Detailed mutational analysis, in vivo chromatin immunoprecipitation, and morpholino knock-downs reveal that transcription factors Pax7 and Msx1/2 cooperate with the neural crest specifier gene, Ets1, to bind to the cranial NC1 regulatory element. However, at vagal/trunk levels, they function together with the neural plate border gene, Zic1, which directly binds to the NC2 enhancer. These results reveal dynamic and differential regulation of FoxD3 in distinct neural crest subpopulations, suggesting that heterogeneity is encrypted at the regulatory level. Isolation of neural crest enhancers not only allows establishment of direct regulatory connections underlying neural crest formation, but also provides valuable tools for tissue specific manipulation and investigation of neural crest cell identity in amniotes.
authors.affiliation: Division of Biology, California Institute of Technology, Pasadena, California, USA.
authors.forename: Marcos S
authors.initials: MS
authors.lastname: Simões-Costa
authors.forename: Sonja J
authors.initials: SJ
authors.lastname: McKeown
authors.forename: Joanne
authors.initials: J
authors.lastname: Tan-Cabugao
authors.forename: Tatjana
authors.initials: T
authors.lastname: Sauka-Spengler
authors.forename: Marianne E
authors.initials: ME
authors.lastname: Bronner
mesh_terms: D000818:Animals; D002454:Cell Differentiation; D002465:Cell Movement; D004252:DNA Mutational Analysis; D053595:Embryonic Stem Cells; D004742:Enhancer Elements, Genetic; D051858:Forkhead Transcription Factors / Q000235:genetics / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D016678:Genome; D051379:Mice; D009432:Neural Crest / Q000166:cytology / Q000378:metabolism; D009474:Neurons / Q000166:cytology / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D015027:Zebrafish / Q000196:embryology / Q000235:genetics / Q000378:metabolism; D029961:Zebrafish Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: C509408:Etv2 protein, zebrafish; D051858:Forkhead Transcription Factors; D014157:Transcription Factors; D029961:Zebrafish Proteins; C491002:foxd3 protein, zebrafish; C492121:zic1 protein, zebrafish