Ida-Yonemochi Hiroko, Harada Hidemitsu, Ohshima Hayato, Saku Takashi
Division of Oral Pathology, Department of Tissue Regeneration and Reconstruction, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan; Division of Anatomy and Cell Biology of the Hard Tissue, Department of Tissue Regeneration and Reconstruction, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan.
Gene Expr Patterns. 2013 Dec;13(8):293-302. doi: 10.1016/j.gep.2013.05.004. Epub 2013 May 27.
Signals of perlecan, an extracellular matrix molecule, which accumulates within the intercellular spaces of the stellate reticulum of the enamel organ, are mediated by at least two receptors, dystroglycan (DG) and integrin β1, in a case-dependent manner in various events in embryogenesis and pathogenesis. This study aims to understand the expression profiles of these two perlecan receptors at both protein and gene levels in murine enamel organ development. Before birth, α-DG was immunolocalized in stellate reticulum cells, in which perlecan was colocalized, while integrin β1 was mainly distributed in the peripheral enamel organ cells as well as the dental mesenchymal cells. On and after postnatal Day 1, the expression of α-DG was dramatically decreased in the stellate reticulum, while integrin β1 was enhanced around blood vessels within the enamel organ. Furthermore, biosyntheses of α-DG and integrin β1 by dental epithelial and pulp mesenchymal cells were confirmed in vitro by using immunofluorescence and reverse-transcriptase polymerase chain reaction. The results suggest that DG is a perlecan receptor that specifically functions in the stellate reticulum of the embryonic stage, but that dental epithelial and mesenchymal cells are maturated by capturing perlecan signals differentially through integrin β1.
基底膜聚糖是一种细胞外基质分子，在釉质器官星网状层的细胞间隙中积累，其信号在胚胎发生和发病机制的各种事件中由至少两种受体——肌营养不良聚糖（DG）和整合素β1以依赖于情况的方式介导。本研究旨在了解这两种基底膜聚糖受体在小鼠釉质器官发育过程中蛋白质和基因水平的表达谱。出生前，α-DG免疫定位在星网状层细胞中，基底膜聚糖与之共定位，而整合素β1主要分布在釉质器官外周细胞以及牙间充质细胞中。出生后第1天及之后，星网状层中α-DG的表达显著降低，而整合素β1在釉质器官内血管周围增强。此外，通过免疫荧光和逆转录聚合酶链反应在体外证实了牙上皮细胞和牙髓间充质细胞对α-DG和整合素β1的生物合成。结果表明，DG是一种在胚胎期星网状层中具有特定功能的基底膜聚糖受体，但牙上皮细胞和间充质细胞通过整合素β1差异性地捕获基底膜聚糖信号而成熟。
