title: Insertion of Cre into the Pax3 locus creates a new allele of Splotch and identifies unexpected Pax3 derivatives.
abstract: Pax3 is a transcription factor expressed in the dorsal neural tube and somite of the developing embryo. It plays critical roles in pre-migratory neural crest cells and in myogenic precursors of skeletal muscle. Pax3-deficient Splotch embryos display neural tube and neural crest defects and lack hypaxial muscles. We have created a new allele of Splotch by replacing the first coding exon with a gene encoding Cre recombinase. This functions as a null allele and no Pax3 protein is detected in homozygous embryos. Heterozygous Pax3(Cre/+) mice display a white belly spot, as do Splotch heterozygotes. Homozygous Pax3(Cre/Cre) embryos are embryonic lethal. We have used Pax3(Cre/+) mice to fate-map Pax3 derivatives in the developing mouse. As expected, neural crest and some somitic derivatives are identified. However, we also detect previously unappreciated derivatives of Pax3-expressing precursors in the colonic epithelium of the hindgut and within the urogenital system.
authors.affiliation: Cardiovascular Division, University of Pennsylvania, Philadelphia, 19104, USA.
authors.forename: Kurt A
authors.initials: KA
authors.lastname: Engleka
authors.forename: Aaron D
authors.initials: AD
authors.lastname: Gitler
authors.forename: Maozhen
authors.initials: M
authors.lastname: Zhang
authors.forename: Diane D
authors.initials: DD
authors.lastname: Zhou
authors.forename: Frances A
authors.initials: FA
authors.lastname: High
authors.forename: Jonathan A
authors.initials: JA
authors.lastname: Epstein
mesh_terms: D000483:Alleles; D000818:Animals; D002465:Cell Movement; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D004622:Embryo, Mammalian / Q000378:metabolism; D005091:Exons; D005821:Genetic Techniques; D005838:Genotype; D006579:Heterozygote; D006720:Homozygote; D015151:Immunoblotting; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D051379:Mice; D008822:Mice, Transgenic; D008957:Models, Genetic; D018482:Muscle, Skeletal / Q000166:cytology; D009474:Neurons / Q000378:metabolism; D000072041:PAX3 Transcription Factor; D051761:Paired Box Transcription Factors; D012333:RNA, Messenger / Q000378:metabolism; D011995:Recombination, Genetic; D013997:Time Factors; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism; D014158:Transcription, Genetic; D001616:beta-Galactosidase / Q000378:metabolism
chemical_list: D004268:DNA-Binding Proteins; D000072041:PAX3 Transcription Factor; D051761:Paired Box Transcription Factors; D012333:RNA, Messenger; D014157:Transcription Factors; C068686:Pax3 protein, mouse; D001616:beta-Galactosidase