title: Expression of the Celsr/flamingo homologue, c-fmi1, in the early avian embryo indicates a conserved role in neural tube closure and additional roles in asymmetry and somitogenesis.
abstract: Flamingo is one of a core group of proteins that regulate planar cell polarity of epithelial structures within the Drosophila embryo while their vertebrate counterparts have been implicated in the coordination of convergent extension movements during gastrulation and in neural tube closure, suggesting that planar polarity mechanisms also function in these processes. Failure of neural tube closure is one of the most common human birth defects, and a murine flamingo (fmi) homologue, Celsr1/fmi-1, was identified as the defective gene in two mouse mutants exhibiting failure of closure 1 of the neural tube. This failure resulted in craniorachischisis in which the neural tube is open from the midbrain posteriorly. The avian embryo provides a tractable system to study neural tube closure. We have identified a chick Celsr1/fmi-1 orthologue, c-fmi1 and provide the first study of expression of an avian flamingo gene. We show that expression is highly dynamic in the early embryo and that c-fmi1 transcripts become enriched within the avian neural epithelium at the initiation of neural tube closure, suggesting a conserved function for Flamingo proteins in this process. Our data also suggest a role for c-fmi1 in myotome development.
authors.affiliation: MRC Centre for Developmental Neurobiology, New Hunts House, Kings College London, London SE1 1UL, UK.
authors.forename: Caroline J
authors.initials: CJ
authors.lastname: Formstone
authors.forename: Ivor
authors.initials: I
authors.lastname: Mason
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001717:Birds; D019521:Body Patterning; D015820:Cadherins / Q000502:physiology*; D002642:Chick Embryo; D018076:DNA, Complementary / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D017403:In Situ Hybridization; D008636:Mesencephalon / Q000196:embryology; D051379:Mice; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000096:biosynthesis* / Q000502:physiology*; D009432:Neural Crest / Q000196:embryology*; D009474:Neurons / Q000378:metabolism; D017434:Protein Structure, Tertiary; D012333:RNA, Messenger / Q000378:metabolism; D011956:Receptors, Cell Surface / Q000502:physiology*; D043562:Receptors, G-Protein-Coupled / Q000096:biosynthesis* / Q000502:physiology*; D017386:Sequence Homology, Amino Acid; D019170:Somites / Q000502:physiology*
chemical_list: D015820:Cadherins; C117380:Celsr1 protein, mouse; C498478:Celsr2 protein, mouse; C444454:Celsr3 protein, mouse; D018076:DNA, Complementary; D009419:Nerve Tissue Proteins; D012333:RNA, Messenger; D011956:Receptors, Cell Surface; D043562:Receptors, G-Protein-Coupled