Conditional inactivation of FGF receptor 2 reveals an essential role for FGF signaling in the regulation of osteoblast function and bone growth.
Human craniosynostosis syndromes, resulting from activating or neomorphic mutations in fibroblast growth factor receptor 2 (FGFR2), underscore an essential role for FGFR2 signaling in skeletal development. Embryos harboring homozygous null mutations in FGFR2 die prior to skeletogenesis. To address the role of FGFR2 in normal bone development, a conditional gene deletion approach was adopted. Homologous introduction of cre recombinase into the Dermo1 (Twist2) gene locus resulted in robust expression of CRE in mesenchymal condensations giving rise to both osteoblast and chondrocyte lineages. Inactivation of a floxed Fgfr2 allele with Dermo1-cre resulted in mice with skeletal dwarfism and decreased bone density. Although differentiation of the osteoblast lineage was not disturbed, the proliferation of osteoprogenitors and the anabolic function of mature osteoblasts were severely affected.
Yu
Kai
K
Department of Molecular Biology and Pharmacology, Washington University Medical School, Campus Box 8103, 660 S. Euclid Avenue, St. Louis, Missouri 63110, USA.
Xu
Jingsong
J
Liu
Zhonghao
Z
Sosic
Drazen
D
Shao
Jiansu
J
Olson
Eric N
EN
Towler
Dwight A
DA
Ornitz
David M
DM
D000818:Animals; D015519:Bone Density; D001846:Bone Development / Q000502:physiology*; D001842:Bone and Bones / Q000000981:diagnostic imaging; D002454:Cell Differentiation / Q000502:physiology; D019070:Cell Lineage; D019902:Chondrocytes / Q000166:cytology / Q000502:physiology; D003398:Craniosynostoses / Q000235:genetics / Q000378:metabolism; D005346:Fibroblast Growth Factors / Q000378:metabolism*; D017353:Gene Deletion; D006801:Humans; D017403:In Situ Hybridization; D019426:Integrases / Q000235:genetics / Q000378:metabolism; D051379:Mice; D018345:Mice, Knockout; D010006:Osteoblasts / Q000166:cytology / Q000502:physiology*; D010641:Phenotype; D011859:Radiography; D020794:Receptor Protein-Tyrosine Kinases / Q000235:genetics / Q000378:metabolism*; D051497:Receptor, Fibroblast Growth Factor, Type 2; D017468:Receptors, Fibroblast Growth Factor / Q000235:genetics / Q000378:metabolism*; D012097:Repressor Proteins; D015398:Signal Transduction / Q000502:physiology*; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D051879:Twist-Related Protein 1; D014764:Viral Proteins / Q000235:genetics / Q000378:metabolism
D017468:Receptors, Fibroblast Growth Factor; D012097:Repressor Proteins; C486274:TWIST2 protein, human; D014157:Transcription Factors; D051879:Twist-Related Protein 1; C096852:Twist2 protein, mouse; D014764:Viral Proteins; D005346:Fibroblast Growth Factors; C496353:FGFR2 protein, human; C496354:Fgfr2 protein, mouse; D020794:Receptor Protein-Tyrosine Kinases; D051497:Receptor, Fibroblast Growth Factor, Type 2; C045073:Cre recombinase; D019426:Integrases