Eda/Edar signaling guides fin ray formation with preceding osteoblast differentiation, as revealed by analyses of the medaka all‐fin less mutant afl. Issue 6 (19th March 2014)

• Record Type: Journal Article
• Authors: Iida, Yuuki; Hibiya, Kenta; Inohaya, Keiji; Kudo, Akira
• Is Part Of: Developmental dynamics. Volume 243:Issue 6(2014:Jun.)
• Page Start: 765
• Page End: 777
• Publication Date: 2014-03-19
• Subjects: Morphogenesis -- Periodicals; Anatomy -- Periodicals; Anatomie -- Périodiques; Biologie du développement -- Périodiques; 571.833
• DOI: 10.1002/dvdy.24120
• Languages: English
• ISSNs: 1058-8388

Abstract

<abstract abstract-type="main"> <title> <x xml:space="preserve">Abstract</x> </title> <p> <underline> <bold>Background:</bold> </underline> Ectodysplasin (Eda) signaling is essential for the morphogenesis of several ectodermal appendages. <underline><bold>Results:</bold></underline> Here, we report a medaka mutant, <italic>all‐fin less</italic> (<italic>afl</italic>), which has a nonsense mutation in its <italic>eda</italic> gene. The adult <italic>afl</italic> fish displayed various abnormalities of its dermal skeleton, such as short and twisted fin rays, missing and abnormally shaped scales and teeth, and skull deformation. Focusing on the developing fin rays in the caudal region of <italic>afl</italic> larvae, we found that the fin rays did not elongate; although the initial formation of fin rays proceeded normally. Additionally, <italic>eda</italic> expression was lost, and the expression pattern of <italic>edar</italic>, the gene for the receptor of Eda, was different from wild‐type one. In vivo imaging of the double‐transgenic medaka expressing enhanced green fluorescent protein under control of the <italic>edar</italic> promoter and DsRed under control of the <italic>osterix</italic> promoter revealed that <italic>edar</italic> expression preceded that of <italic>osterix</italic> and that the <italic>edar</italic>‐expressing cells migrated in the direction of fin ray elongation, indicating that the Eda/Edar signaling event precedes osteoblast differentiation. <underline><bold>Conclusions:</bold></underline> Our findings provide evidence that Eda signaling accompanied with the binding of Eda to Edar are essential for fin ray formation guided by cell migration. <italic>Developmental Dynamics 243:765–777, 2014</italic>. © 2014 Wiley Periodicals, Inc.</p> </abstract>