title: Fgfr1 regulates patterning of the pharyngeal region.
abstract: Development of the pharyngeal region depends on the interaction and integration of different cell populations, including surface ectoderm, foregut endoderm, paraxial mesoderm, and neural crest. Mice homozygous for a hypomorphic allele of Fgfr1 have craniofacial defects, some of which appeared to result from a failure in the early development of the second branchial arch. A stream of neural crest cells was found to originate from the rhombomere 4 region and migrate toward the second branchial arch in the mutants. Neural crest cells mostly failed to enter the second arch, however, but accumulated in a region proximal to it. Both rescue of the hypomorphic Fgfr1 allele and inactivation of a conditional Fgfr1 allele specifically in neural crest cells indicated that Fgfr1 regulates the entry of neural crest cells into the second branchial arch non-cell-autonomously. Gene expression in the pharyngeal ectoderm overlying the developing second branchial arch was affected in the hypomorphic Fgfr1 mutants at a stage prior to neural crest entry. Our results indicate that Fgfr1 patterns the pharyngeal region to create a permissive environment for neural crest cell migration.
authors.affiliation: Institute of Biotechnology, Viikki Biocenter, 00014-University of Helsinki, Finland.
authors.forename: Nina
authors.initials: N
authors.lastname: Trokovic
authors.forename: Ras
authors.initials: R
authors.lastname: Trokovic
authors.forename: Petra
authors.initials: P
authors.lastname: Mai
authors.forename: Juha
authors.initials: J
authors.lastname: Partanen
mesh_terms: D000483:Alleles; D000818:Animals; D017209:Apoptosis; D001934:Branchial Region / Q000473:pathology; D002465:Cell Movement; D002972:Cleft Palate / Q000196:embryology / Q000235:genetics; D019465:Craniofacial Abnormalities / Q000196:embryology / Q000235:genetics; D004432:Ear, Middle / Q000002:abnormalities / Q000196:embryology; D004475:Ectoderm / Q000378:metabolism; D004848:Epithelium / Q000196:embryology; D018507:Gene Expression Regulation, Developmental; D005804:Genes, Lethal; D006928:Hyoid Bone / Q000002:abnormalities / Q000196:embryology; D019426:Integrases / Q000235:genetics / Q000502:physiology; D051379:Mice; D009024:Morphogenesis / Q000235:genetics; D009432:Neural Crest / Q000166:cytology*; D010614:Pharynx / Q000196:embryology*; D011518:Proto-Oncogene Proteins / Q000235:genetics / Q000502:physiology; D020794:Receptor Protein-Tyrosine Kinases / Q000502:physiology*; D051496:Receptor, Fibroblast Growth Factor, Type 1; D017468:Receptors, Fibroblast Growth Factor / Q000502:physiology*; D011993:Recombinant Fusion Proteins / Q000502:physiology; D012249:Rhombencephalon / Q000002:abnormalities / Q000196:embryology; D014764:Viral Proteins / Q000235:genetics / Q000502:physiology; D051153:Wnt Proteins; D029961:Zebrafish Proteins
chemical_list: D011518:Proto-Oncogene Proteins; D017468:Receptors, Fibroblast Growth Factor; D011993:Recombinant Fusion Proteins; D014764:Viral Proteins; D051153:Wnt Proteins; D029961:Zebrafish Proteins; C496349:Fgfr1 protein, mouse; D020794:Receptor Protein-Tyrosine Kinases; D051496:Receptor, Fibroblast Growth Factor, Type 1; C045073:Cre recombinase; D019426:Integrases