title: Evx1 is required for joint formation in zebrafish fin dermoskeleton.
abstract: The transcription factor Evx1 is expressed in the joints between individual lepidotrichia (bony ray) segments and at the distal tips of the lepidotrichia in developing zebrafish fins. It is also expressed in the apical growth zone in regenerating fins. However, so far there is no functional evidence that addresses whether Evx1 is required for any aspect of fin development or regeneration. In this study, we use a novel mutation in evx1 to address this. We find that Evx1 is not required for either fin outgrowth or regeneration. All of the fins form normally in evx1 mutants, and there are no significant changes in fin length. In contrast, Evx1 is required for lepidotrichia joint formation during both fin development and regeneration. This is a very specific phenotype as both lepidotrichia hemisegment separations and lepidotrichia bifurcations still form normally in evx1 mutant fins, as do joints in the more proximal endoskeletal radials.
authors.affiliation: Department of Physiology, Development and Neuroscience, Anatomy Building, Cambridge, UK.
authors.forename: Claus J
authors.initials: CJ
authors.lastname: Schulte
authors.forename: Claire
authors.initials: C
authors.lastname: Allen
authors.forename: Samantha J
authors.initials: SJ
authors.lastname: England
authors.forename: José L
authors.initials: JL
authors.lastname: Juárez-Morales
authors.forename: Katharine E
authors.initials: KE
authors.lastname: Lewis
mesh_terms: D058500:Animal Fins / Q000196:embryology / Q000378:metabolism*; D000818:Animals; D018507:Gene Expression Regulation, Developmental; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism*; D017403:In Situ Hybridization; D007596:Joints / Q000196:embryology* / Q000378:metabolism*; D015027:Zebrafish / Q000196:embryology* / Q000378:metabolism*; D029961:Zebrafish Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: D018398:Homeodomain Proteins; D029961:Zebrafish Proteins; C425331:evx1 protein, zebrafish