Expression and regulation of chicken fibroblast growth factor homologous factor (FHF)-4 during craniofacial morphogenesis

✍ Scribed by Ignacio Muñoz-Sanjuán; Michael K. Cooper; Philip A. Beachy; John F. Fallon; Jeremy Nathans

• Publisher: John Wiley and Sons
• Year: 2001
• Tongue: English
• Weight: 498 KB
• Volume: 220
• Category: Article
• ISSN: 1058-8388
• DOI: 10.1002/1097-0177(20010301)220:3<238::aid-dvdy1104>3.0.co;2-t

✦ Synopsis

Fibroblast growth factor homologous factors (FHFs) have been implicated in limb and nervous system development. In this paper we describe the expression of the cFHF-4 gene during chicken craniofacial development. cFHF-4 is expressed in the mesenchyme of the frontonasal process, and in the mesenchyme and ectoderm of the mandibular processes. The expression of cFHF-4 and other genes implicated in facial patterning have been analyzed in talpid 2 embryos or in the presence of exogenous retinoic acid. Talpid 2 mutants show abnormal patterns of gene expression, including up-regulation of cFHF-4 in the developing face, which correlate with defects in cartilage formation. By contrast, expression of cFHF-4 in the developing face is strongly downregulated by teratogenic doses of all-trans retinoic acid in a dose-dependent manner. Low levels of retinoic acid that produce distal upper beak truncations do not affect cShh, c-Patched-1, or c-Bmp-2 expression in the face, but downregulate cFHF-4 in the frontonasal process.