FoxN3 knock-down alters spatio-temporal expression patterns of genes involved in cranial cartilage and muscle development in the African clawed-frog Xenopus laevis

Title: FoxN3 knock-down alters spatio-temporal expression patterns of genes involved in cranial cartilage and muscle development in the African clawed-frog Xenopus laevis

Creators: Jennifer Schmidt, Maximilian Schuff, Benjamin Naumann, Lennart Olsson

Submitted May 19, 2020.
Accepted August 12, 2020.
Published online at www.senckenberg.de/vertebrate-zoology on September 9, 2020.
Published in print Q3/2020.

DOI: 10.26049/VZ70-3-2020-14
PDF/A 3.6 MB

Published by Senckenberg Gesellschaft für Naturforschung

Date (Publication Year): 2020

Resource Type (General): TEXT

Resource Type (optional): Vertebrate Zoology, Scientific Article

Description (en): What is the gene regulatory network underlying the morphogenesis of the vertebrate head skeleton? A good candidate to approach this question is the FoxN3 gene. Morpholino-mediated FoxN3 knock-down leads to a delay in cranial cartilage and muscle formation, to reduced size and to malformations of both cartilages and muscles in Xenopus laevis. Additionally, muscle fiber development and joint formation are incomplete. We used qRT-PCR and whole-mount in situ hybridization to analyse potential target genes of FoxN3. The spatio-temporal expressions of different cartilage, muscle, and joint markers as well as cell adhesion molecules are changed following FoxN3 knock-down. Expression of N-CAM and N-Cad is decreased throughout development and expression of genes important for cartilage formation (Sox9, Col2α1, Runx2) is delayed. Joint markers (Gdf5/6) and genes (Dlx5/6) important for regional specification are also down-regulated and bagpipe genes show decreased expression at consecutive stages. Expression levels of key myogenic genes (Myf5, MyoD, MHC) are at 30 – 40% of control expression. These results indicate that FoxN3 occupies a key position in the gene regulatory network maintaining normal development of cranial cartilages and muscles as well as jaw joint formation.

Key words: Chondrogenesis, forkhead transcription factor, HDAC, myogenesis, neural crest.

Citation: Schmidt, J., Schuff, M., Naumann, B., Olsson, L. (2020). FoxN3 knock-down alters spatio-temporal expression patterns of genes involved in cranial cartilage and muscle development in the African clawed-frog Xenopus laevis. Vertebrate Zoology, 70(3): 455-472. https://doi.org/10.26049/VZ70-3-2020-14