Rosenquist T A, Martin G R
Department of Anatomy, University of California at San Francisco 94143-0452, USA.
Dev Dyn. 1996 Apr;205(4):379-86. doi: 10.1002/(SICI)1097-0177(199604)205:4<379::AID-AJA2>3.0.CO;2-F.
Using RNA in situ hybridization analysis, we have characterized the expression domains of the four known members of the FGF receptor-tyrosine kinase gene family in the murine hair follicle at various stages of the hair growth cycle. During anagen, we detected Fgfr1 RNA in the dermal papilla, Fgfr2 RNA in hair matrix cells near the dermal papilla, Fgfr3 RNA in pre-cuticle cells in the periphery of the hair bulb, and Fgfr4 RNA in cells in the periphery of the hair bulb and also in the inner and outer root sheath in the lower half of the follicle neck. No RNA expression of these genes was detected during late catagen or telogen. We have previously shown that Fgf5 is expressed in the outer root sheath in the transient portion of the follicle (Hébert et al. [1994] Cell 78:1017-1025). In the present study we have also assayed for the expression of six other members of the FGF ligand gene family, Fgf3, Fgf4, Fgf6, Fgf7, Fgf8, and Fgf9. Among these FGF genes, only Fgf7 was found to be expressed in the hair follicle. Fgf7 RNA is localized to the dermal papilla during anagen, but expression is down-regulated by the late-anagen VI stage. We have also demonstrated that addition of FGF5 protein to the culture medium changes the behavior of dermal papilla cells in vitro, indicating that they are capable of responding to FGF5. Together with previously published data, these results provide a complete analysis of FGF ligand and FGF receptor-tyrosine kinase gene expression in the hair follicle, and suggest that FGF signalling may have several functions in the hair growth cycle.
通过RNA原位杂交分析，我们已对成纤维细胞生长因子（FGF）受体 - 酪氨酸激酶基因家族的四个已知成员在小鼠毛囊生长周期不同阶段的表达区域进行了表征。在生长期，我们在真皮乳头中检测到Fgfr1 RNA，在真皮乳头附近的毛基质细胞中检测到Fgfr2 RNA，在毛球周边的前角质形成细胞中检测到Fgfr3 RNA，在毛球周边的细胞以及毛囊颈部下半部分的内根鞘和外根鞘中检测到Fgfr4 RNA。在退行期晚期或休止期未检测到这些基因的RNA表达。我们之前已表明Fgf5在毛囊短暂部分的外根鞘中表达（Hébert等人，[1994]《细胞》78:1017 - 1025）。在本研究中，我们还检测了FGF配体基因家族的其他六个成员Fgf3、Fgf4、Fgf6、Fgf7、Fgf8和Fgf9的表达。在这些FGF基因中，仅发现Fgf7在毛囊中表达。Fgf7 RNA在生长期定位于真皮乳头，但在生长期晚期VI阶段表达下调。我们还证明，向培养基中添加FGF5蛋白会改变体外真皮乳头细胞的行为，表明它们能够对FGF5作出反应。连同先前发表的数据，这些结果提供了对毛囊中FGF配体和FGF受体 - 酪氨酸激酶基因表达的完整分析，并表明FGF信号传导可能在毛囊生长周期中具有多种功能。
