Duplication and divergence of fgf8 functions in teleost development and evolution
Article first published online: 20 AUG 2007
Copyright © 2007 Wiley-Liss, Inc., A Wiley Company
Journal of Experimental Zoology Part B: Molecular and Developmental Evolution
Volume 308B, Issue 6, pages 730–743, 15 December 2007
How to Cite
Jovelin, R., He, X., Amores, A., Yan, Y.-l., Shi, R., Qin, B., Roe, B., Cresko, W. A. and Postlethwait, J. H. (2007), Duplication and divergence of fgf8 functions in teleost development and evolution. J. Exp. Zool., 308B: 730–743. doi: 10.1002/jez.b.21193
- Issue published online: 5 NOV 2007
- Article first published online: 20 AUG 2007
- Manuscript Accepted: 22 JUL 2007
- Manuscript Revised: 16 JUL 2007
- Manuscript Received: 5 MAR 2007
- National Center for Research Resources. Grant Number: 5R01RR020833
- National Institutes of Health. Grant Number: P01 HD22486.
Fibroblast growth factors play critical roles in many aspects of embryo patterning that are conserved across broad phylogenetic distances. To help understand the evolution of fibroblast growth factor functions, we identified members of the Fgf8/17/18-subfamily in the three-spine stickleback Gasterosteus aculeatus, and investigated their evolutionary relationships and expression patterns. We found that fgf17b is the ortholog of tetrapod Fgf17, whereas the teleost genes called fgf8 and fgf17a are duplicates of the tetrapod gene Fgf8, and thus should be called fgf8a and fgf8b. Phylogenetic analysis supports the view that the Fgf8/17/18-subfamily expanded during the ray-fin fish genome duplication. In situ hybridization experiments showed that stickleback fgf8 duplicates exhibited common and unique expression patterns, indicating that tissue specialization followed the gene duplication event. Moreover, direct comparison of stickleback and zebrafish embryonic expression patterns of fgf8 co-orthologs suggested lineage-specific independent subfunction partitioning and the acquisition or the loss of ortholog functions. In tetrapods, Fgf8 plays an important role in the apical ectodermal ridge of the developing pectoral appendage. Surprisingly, differences in the expression of fgf8a in the apical ectodermal ridge of the pectoral fin bud in zebrafish and stickleback, coupled with the role of fgf16 and fgf24 in teleost pectoral appendage show that different Fgf genes may play similar roles in limb development in various vertebrates. J. Exp. Zool. (Mol. Dev. Evol.) 308B:730–743, 2007. © 2007 Wiley-Liss, Inc.