Expression profile of critical genes involved in FGF signaling pathway in the developing human primary dentition.
Mammalian tooth development is regulated by paracrine signal molecules of several conserved family interactions between epithelium and mesenchyme. The expression patterns and regulative roles of FGF signaling have been extensively studied in the mouse odontogenesis; however, that is not well known in human tooth development. In order to unveil the molecular mechanisms that regulate human tooth morphogenesis, we examined the expression patterns of the critical molecules involved in FGF signaling pathway in the developing human tooth germ by in situ hybridization, immunohistochemistry, and real-time RT-PCR, including FGF ligands, receptors, and intracellular transducer. We found overlapping but distinct expression pattern of FGF ligands and receptors in the different stages and components. Expression of FGF4, FGF7, FGF8, and FGF9 persists widespread in human tooth mesenchyme, which is quite different to that of in mouse. FGFR1 may be the major receptor in regulate mechanisms of FGF signals in human tooth development. Real-time RT-PCR indeed confirmed the results of in situ hybridization. Results of K-Ras, p-ERK1/2, p-p38, p-JNK, and p-PDK1 expression reveal spatial and temporal patterns of FGF signaling during morphogenesis and organogenesis of human tooth germ. Activity of the FGF signaling transducer protein in human tooth germ was much higher than that of in mouse. Our results provided important FGF singling information in the developing process, pinpoint to the domains where the downstream target genes of FGF signaling can be sought, and enlightened our knowledge about the nature of FGF signaling in human tooth germ.
Center for Biomedicine Research of South China, Fujian Key Laboratory of Developmental and Neuro Biology, College of Life Science, Fujian Normal University, Fuzhou, 350108, Fujian, People's Republic of China.
Feng
F
Huang
Center for Biomedicine Research of South China, Fujian Key Laboratory of Developmental and Neuro Biology, College of Life Science, Fujian Normal University, Fuzhou, 350108, Fujian, People's Republic of China.
Xiaoxiao
X
Hu
Center for Biomedicine Research of South China, Fujian Key Laboratory of Developmental and Neuro Biology, College of Life Science, Fujian Normal University, Fuzhou, 350108, Fujian, People's Republic of China.
Chunni
C
Fang
Center for Biomedicine Research of South China, Fujian Key Laboratory of Developmental and Neuro Biology, College of Life Science, Fujian Normal University, Fuzhou, 350108, Fujian, People's Republic of China.
Hong
H
Liu
Center for Biomedicine Research of South China, Fujian Key Laboratory of Developmental and Neuro Biology, College of Life Science, Fujian Normal University, Fuzhou, 350108, Fujian, People's Republic of China.
Chensheng
C
Lin
Center for Biomedicine Research of South China, Fujian Key Laboratory of Developmental and Neuro Biology, College of Life Science, Fujian Normal University, Fuzhou, 350108, Fujian, People's Republic of China. ydzhang@fjnu.edu.cn.
Yanding
Y
Zhang
Center for Biomedicine Research of South China, Fujian Key Laboratory of Developmental and Neuro Biology, College of Life Science, Fujian Normal University, Fuzhou, 350108, Fujian, People's Republic of China. bioxfh@fjnu.edu.cn.
Xuefeng
X
Hu
D005260:Female; D005346:Fibroblast Growth Factors / Q000235:genetics* / Q000378:metabolism*; D020869:Gene Expression Profiling; D006801:Humans; D007150:Immunohistochemistry; D011247:Pregnancy; D060888:Real-Time Polymerase Chain Reaction; D015398:Signal Transduction / Q000235:genetics*; D014094:Tooth, Deciduous / Q000254:growth & development* / Q000378:metabolism*
D005346:Fibroblast Growth Factors
FGF signaling; Gene expression; Human tooth