Proteoglycan-collagen XV in human tissues is seen linking banded collagen fibers subjacent to the basement membrane
Proteoglycan-collagen XV in human tissues is seen linking banded collagen fibers subjacent to the basement membrane
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DOI：
10.1369/jhc.4a6376.2005
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发表时间：
2005-02-01
影响因子：
3.2
通讯作者：
Myers, JC
中科院分区：
文献类型：
--
作者：
Amenta, PS;Scivoletti, NA;Myers, JC
XV型是在所有检查的人体组织中发现的大胶原蛋白多糖。光镜下，除肾小球毛细血管和肝/脾血窦外，大多数上皮细胞和所有神经、肌肉、脂肪和内皮基底膜区均有表达。这种广泛的分布表明，XV型可能是一个离散的结构组成部分，其作用是将基底膜粘附到下面的结缔组织上。为了解决这些问题，进行了人肾脏、胎盘和结肠中XV型胶原的免疫金超微结构分析。令人惊讶的是，发现XV型几乎完全与非常接近基底膜的纤维状胶原网络相关。XV型表现出直接在纤维表面上或从纤维延伸成线性或簇状阵列的焦点外观。最常见的单一排列是XV型金颗粒连接厚带状纤维的桥。XV型在这种限制性微环境中的功能预期对其与糖胺聚糖链的修饰具有内在依赖性。目前的生物化学表征表明，XV型核心蛋白在体内携带的链软骨素/硫酸克莱马坦单独，或软骨素/硫酸克莱马坦与硫酸乙酰肝素在不同的比例。因此，XV型胶原可能作为结构组织者来维持基底膜下的多孔网络，并且在该域中可能在信号转导途径中起关键作用。
Type XV is a large collagen-proteoglycan found in all human tissues examined. By light microscopy it was localized to most epithelial and all nerve, muscle, fat and endothelial basement membrane zones except for the glomerular capillaries or hepatic/ splenic sinusoids. This widespread distribution suggested that type XV may be a discrete structural component that acts to adhere basement membrane to the underlying connective tissue. To address these issues, immunogold ultrastructural analysis of type XV collagen in human kidney, placenta, and colon was conducted. Surprisingly, type XV was found almost exclusively associated with the fibrillar collagen network in very close proximity to the basement membrane. Type XV exhibited a focal appearance directly on the surface of, or extending from, the fibers in a linear or clustered array. The most common single arrangement was a bridge of type XV gold particles linking thick-banded fibers. The function of type XV in this restricted microenvironment is expected to have an intrinsic dependence upon its modification with glycosaminoglycan chains. Present biochemical characterization showed that the type XV core protein in vivo carries chains of chondroitin/clermatan sulfate alone, or chondroitin/clermatan sulfate together with heparan sulfate in a differential ratio. Thus, type XV collagen may serve as a structural organizer to maintain a porous meshwork subjacent to the basement membrane, and in this domain may play a key role in signal transcluction pathways.