Reconstruction of basement membranes aiming at artificial organs

针对人工器官的基底膜重建

基本信息

批准号：
10557113
负责人：
NINOMIYA Yoshifumi
金额：
$ 8.26万
依托单位：
OKAYAMA UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B).
财政年份：
1998
资助国家：
日本
起止时间：
1998 至 2000
项目状态：
已结题

项目摘要

Ultimate goal of the research project is to make artificial organs to insert basement membrane materials between epithelial layers and extracellular matrix. In order to make type IV collagen molecules in vitro, we we did the following investigations :* Molecular composition of basement membranes underneath smooth muscle cells varies in different organs, which could be related to specific function of the individual organs.* We first isolated and characterized genomic DNA fragments that cover the 5'flanking sequences of COL4A3 and COL4A4 genes, which provided information to delineate the promoter activity for the tissue-specific expression of the six type IV collagen genes.* Molecular forms of collagen IV in follicle basement membranes are different in development.* We identified interactions between the α2(IV) and ProMMP-9 by immunoprecipitations and blotting.* Basement membrane collagen IV molecules diminish in parallel with malignancy and invasiveness when analyzed in tumor progression.* Although mRNA expression level of α5 decreased in kidney of a canine Alport case, that of α6 resulted in unchanged. But the protein level of both chains cannot be found any. These results suggest a possibility of a molecular form of α5/α6.* Differential expression of collagen IV genes in epithelial basement membranes was analyzed in detail.* Here we define a novel function for soluble non-collagenous (NC1) domains of the α2(IV), α3(IV), and α6(IV) chains of human collagen type IV in the regulation of angiogenesis and tumor growth. These NCI domains were shown to regulate endothelial cell adhesion and migration by distinct αv and β1 integrin-dependent mechanisms.* In Lmx1b(-/-) mice, expression of both α3 and α4 is strongly diminished in GBM, whereas that of α1, α2 and α5 is unchanged. Moreover, LMX1B binds specifically to a putative enhancer in intron 1 of mouse/human COL4A4 and upregulates reporter constructs containing the enhancer-like sequence.

研究项目的最终目标是使人造器官在上皮层和细胞外基质之间插入基底膜材料。为了在体外制作IV型胶原分子，我们进行了以下研究：*平滑肌细胞下基底膜的分子组成在不同的器官中有所不同，这可能与单个器官的特定功能有关。卵泡地下膜中六种IV胶原蛋白基因的组织特异性表达。*分子形式的胶原蛋白IV在发育中不同。尽管犬Alport病例的肾脏中α5的mRNA表达水平降低，但α6的mRNA表达水平降低，但α6的mRNA表达水平却没有变化。但是两种链的蛋白质水平都找不到。这些结果表明，详细分析了上皮地下膜中胶原蛋白IV基因的分子形式的差异表达的可能性。血管生成和肿瘤生长。这些NCI结构域被证明可以调节内皮细胞粘附和通过不同的αV和β1整合素依赖性机制的迁移。此外，LMX1B专门与小鼠/人Col4a4内含子1中的假定增强剂结合，并上调包含增强子样序列的记者构建体。