Cloning and expression analysis of Fgf5, 6 and 7 during early chick development.
FGFs with similar sequences can play different roles depending on the model organisms examined. Determining these roles requires knowledge of spatio-temporal Fgf gene expression patterns. In this study, we report the cloning of chick Fgf5, 6 and 7, and examine their gene expression patterns by whole mount in situ hybridization. We show that Fgf5's spatio-temporally restricted expression pattern indicates a potentially novel role during inner ear development. Fgf6 and Fgf7, although belonging to different subfamilies with diverged sequences, are expressed in similar patterns within the mesoderm. Alignment of protein sequences and phylogenetic analysis demonstrate that FGF5 and FGF6 are highly conserved between chick, human, mouse and zebrafish. FGF7 is similarly conserved except for the zebrafish, which has considerably diverged.
Author contributions ::: ::: GH helped design the study, establish the animal model, collect and analyze samples, and write the manuscript. YY and DH helped establish the animal model, performed Western blotting, immunohistochemistry analyses. YY and DH also helped analyse data and revise the manuscript. QYW and JK contributed to study planning, analyse and interpret data, review and revise the manuscript. All authors have approved the final version of this article to be published and agreed to be accountable for all aspects of the work in ensuring the questions related to the accuracy or integrity of any part of the work. ::: ::: ::: ::: Disclosure ::: ::: The authors report no conflicts of interest in this work.