Exploration of the new components for elastic fiber assembly

为了研究弹性纤维组装的新成分，我们将重点放在日光弹性增殖症上，其特征是观察到成人真皮中异常的弹性纤维。首先，我们评估了紫外线照射后，新生儿和成人真皮成纤维细胞之间的mRNA表达。由于RT-qPCR显示与赖氨酰氧化酶相关的mRNA表达存在差异，因此我们阐明了赖氨酰氧化酶在弹力形成中的作用。赖氨酰氧化酶是已知的在原弹性蛋白或胶原分子之间的交联剂，导致弹性纤维或胶原纤维成熟。我们发现，赖氨酰氧化酶影响原弹性蛋白在微原纤维上的沉积，并在弹性纤维组装的早期阶段定位于细胞表面。此外，在成人真皮成纤维细胞中，细胞表面赖氨酰氧化酶的释放延迟，导致弹性纤维的异常组装。这些数据表明，赖氨酰氧化酶的释放是弹力形成的关键步骤。

To investigate the new components for elastic fiber assembly, we focused on the solar elastosis, of which characterization is observed the abnormal elastic fiber in adult dermis. First, we assess the mRNA expression between the dermal fibroblast from neonatal and adult after UV radiation. Because RT-qPCR showed the difference in mRNA expression which related to lysyl oxidase, we clarified the function of lysyl oxidase in elastogenesis. Lysyl oxidase is known to cross-linker between tropoelastin or collagen molecules, resulting in maturatation of elastic fibers or collagen fibers. We found that lysyl oxidase affects the deposition of tropoelastin onto microfibril fibers and localizes on the cell surface in early stage of elastic fiber assembly. Further, the release of lysyl oxidase form the cell surface was delayed in adult dermal fibroblast, resulting in abnormal assembly of elastic fiber. These data suggests that the release of lysyl oxidase is key step of elastogenesis.