A truncated FGF receptor blocks neural induction by endogenous Xenopus inducers.

We have examined the role of fibroblast growth factor (FGF) signalling in neural induction. The approach takes advantage of the fact that both noggin and the dominant negative mutant activin receptor (delta1XAR1) directly induce neural tissues in the absence of dorsal mesoderm. A truncated FGF receptor (XFD) is co-expressed with noggin or delta1XAR1 in both whole embryos and isolated animal caps.

Comparative analysis of the tissue distribution of three fibroblast growth factor receptor mRNAs during amphibian morphogenesis.

We have used in situ hybridization to survey the expression pattern of three fibroblast growth factor receptor (FGFR) mRNAs (PFR-1, PFR-3 and PFR-4, which we previously identified as the amphibian Pleurodeles waltl homologs of human FGFR-1, FGFR-3 and FGFR-4, respectively) during morphogenesis. Previous work suggests that these FGFR mRNAs exhibit a distinct pattern of expression at early developmental stages. In the present study we have tested the functional activity of these receptors and shown that both FGF-1 (acidic FGF) and FGF-2 (basic FGF), but not FGF-7 (keratinocyte growth factor), can lead to their activation, suggesting that the three cDNAs encode functional receptors.

Expression of fibroblast growth factor receptor-2 splice variants is developmentally and tissue-specifically regulated in the amphibian embryo.

There is increasing evidence that distinct fibroblast growth factor receptor (FGFR) genes are involved in embryonic development and that unique expression patterns of individual FGFRs correlate with tissue-specific functions. In addition, alternative splicing of mRNA transcripts from at least two of these genes (FGFR-1 and FGFR-2) can generate receptor variants with different ligand-binding specificity. By polymerase chain reaction methods and by screening a cDNA library, we have isolated five amphibian FGFR-2 splice variants which share a high degree of identity to their human counterparts.

Isolation and developmental expression of the amphibian homolog of the fibroblast growth factor receptor 3.

Recent observations suggest that fibroblast growth factors (FGFs) and their receptors are involved in the control of embryogenesis. Several FGF receptor genes have been identified so far and their expression is differentially regulated. As part of a continuing effort to analyse the differential expression of FGF receptors and their potential role during amphibian development, we have isolated a Pleurodeles homolog of FGF receptor 3 (FGFR-3), which we designated PFR-3 because of its highest homology to human FGFR-3 (75% overall identity).