The fibroblast growth factor family consists of a large number of secreted polypeptide growth factors. The developmental importance of the family has been highlighted in many studies, which serve to underscore their role as local instructive signals directing diverse processes in the developing embryo. We wished to characterize and compare the expression patterns of nine members of the fibroblast growth factor family in the chick embryo. In this study, we survey the expression patterns of fgf-2, -3, -4, -8, -10, -12, -13, -14 and -18 during gastrula and neurula stages (Hamburger and Hamilton stages: 4-13). As well as providing a comparison of the expression patterns of those fibroblast growth factors already published, we provide new data on the expression patterns of some of these genes at early stages.

The inner ear, which mediates hearing and equilibrium, develops from an ectodermal placode located adjacent to the developing hindbrain. Induction of the placode and its subsequent morphogenesis and differentiation into the inner ear epithelium and its sensory neurons, involves signalling interactions within and between otic and non-otic tissues. Several members of the fibroblast growth factor (FGF) family play important roles at various stages of otic development; however, there are additional family members that have not been evaluated. In this study, we surveyed the expression patterns of 18 mouse Fgf and 3 Fgf receptor (Fgfr) genes during early otic development. Two members of the Fgf family, Fgf4 and Fgf16, and all three tested members of the Fgfr family, Fgfr2c, Fgfr3c, and Fgfr4, were expressed in tissues relevant to inner ear development. Fgf4 transcripts were expressed in the preplacodal and placodal ectoderm, suggesting potential roles in placode induction and/or maintenance.

Members of the extensive fibroblast growth factor (FGF) family play many key roles during embryonic development. In later development, during the course of organogenesis, these factors have been shown to direct distinct cellular pathways within the context of a particular organ system. To gain more insight into the processes that these factors may be controlling, we conducted a survey of the expression of known FGF family members in chick embryos at stages 18 -25. We show the expression patterns of