Adab K, Sayne J R, Carlson D S, Opperman L A
Department of Biomedical Sciences, Baylor College of Dentistry, Texas A & M University System Health Science Center, Dallas 75246, USA.
Orthod Craniofac Res. 2002 Nov;5(4):227-37. doi: 10.1034/j.1600-0544.2002.02227.x.
It is hypothesized that regulation of facial suture morphogenesis is similar to that of cranial sutures, with expression of similar regulatory molecules, governing suture formation and patency. The present study was designed to characterize the morphology of the frontonasal (FN) suture of the rat at different developmental stages and to investigate the presence and temporal-spatial expression of transforming growth factor-beta 1 (Tgf-beta1), Tgf-beta2, Tgf-beta3 and Msx2 mRNA within these structures.
The Department of Biomedical Sciences at Texas A&M University System Health Science Center, Baylor College of Dentistry, Dallas, TX USA. Histological sections and RNA isolated from FN suture tissues of Sprague-Dawley rats, aged embryonic day 16 through postnatal day 20.
Sections were examined after immunohistochemical staining. Gene expression was determined by densitometric analysis of RT-PCR products run on agarose gels.
FN sutures develop slightly later than cranial sutures and show increased complexity over time when compared to cranial sutures. FN sutures were closely associated with the nasal capsular cartilage, with intervening layers of perichondrium and periosteum. The pattern of expression of Tgf-betas within the FN suture tissues was similar to that seen in the cranial sutures. However, mRNA and protein of the Tgf-betas were differentially expressed over time compared to cranial sutures. In FN sutures, Tgf-beta mRNA levels were elevated both during the period of suture morphogenesis and during active bone growth from the suture in the early postnatal period. Msx2 mRNA expression was elevated in both the prenatal and postnatal periods, similar to Tgf-beta mRNA expression.
Tgf-beta and Msx2 are present in facial sutures similar to cranial sutures, but are differentially expressed over time, perhaps reflecting different bone growth rates from these sutures.
据推测，面部缝形态发生的调控与颅缝相似，存在相似的调控分子表达，控制着缝的形成和通畅。本研究旨在描述大鼠不同发育阶段额鼻（FN）缝的形态，并研究转化生长因子-β1（Tgf-β1）、Tgf-β2、Tgf-β3和Msx2 mRNA在这些结构中的存在情况及时空表达。
美国得克萨斯州达拉斯贝勒牙科学院，得克萨斯农工大学系统健康科学中心生物医学科学系。从胚胎第16天至出生后第20天的Sprague-Dawley大鼠的FN缝组织中分离出组织学切片和RNA。
免疫组织化学染色后检查切片。通过对琼脂糖凝胶上的RT-PCR产物进行光密度分析来确定基因表达。
FN缝的发育略晚于颅缝，与颅缝相比，随时间推移其复杂性增加。FN缝与鼻囊软骨紧密相连，其间有软骨膜和骨膜层。FN缝组织中Tgf-β的表达模式与颅缝中所见相似。然而，与颅缝相比，Tgf-β的mRNA和蛋白随时间差异表达。在FN缝中，Tgf-β mRNA水平在缝形态发生期和出生后早期缝的活跃骨生长期间均升高。Msx2 mRNA表达在产前和产后均升高，与Tgf-β mRNA表达相似。
Tgf-β和Msx2存在于与颅缝相似的面部缝中，但随时间差异表达，这可能反映了这些缝不同的骨生长速率。
