Evx1 is required for joint formation in zebrafish fin dermoskeleton

Dev Dyn. 2011 May;240(5):1240-8. doi: 10.1002/dvdy.22534. Epub 2011 Jan 18.


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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animal Fins / embryology
  • Animal Fins / metabolism*
  • Animals
  • Gene Expression Regulation, Developmental
  • Homeodomain Proteins / genetics
  • Homeodomain Proteins / metabolism*
  • In Situ Hybridization
  • Joints / embryology*
  • Joints / metabolism*
  • Zebrafish / embryology*
  • Zebrafish / metabolism*
  • Zebrafish Proteins / genetics
  • Zebrafish Proteins / metabolism*


  • Homeodomain Proteins
  • Zebrafish Proteins
  • evx1 protein, zebrafish