Grant-in-Aid for Scientific Research (B).
|Allocation Type||Single-year Grants|
|Research Institution||OKAYAMA UNIVERSITY|
NINOMIYA Yoshifumi Okayama University, Medical School, Professor, 医学部, 教授 (70126241)
YONEZAWA Tomoko Okayama University Medical School, Assistant, 医学部, 助手 (30304299)
MOMOTA Ryusuke Okayama University, Medical School, Assistant, 医学部, 助手 (80263557)
OOHASHI Toshitaka Okayama University, Medical School, Lecturer, 医学部, 講師 (50194262)
植木 靖好 岡山大学, 医学部, 助手 (60304309)
|Project Period (FY)
1998 – 2000
Completed(Fiscal Year 2000)
|Budget Amount *help
¥12,900,000 (Direct Cost : ¥12,900,000)
Fiscal Year 2000 : ¥3,000,000 (Direct Cost : ¥3,000,000)
Fiscal Year 1999 : ¥3,400,000 (Direct Cost : ¥3,400,000)
Fiscal Year 1998 : ¥6,500,000 (Direct Cost : ¥6,500,000)
|Keywords||basement membrane / collagen / tissue engineering / gene expression / IV型コラーゲン / トランスフェクション / 免疫沈降 / コラーゲン分子 / 超分子会合体 / 発現ベクター / 無細胞翻訳 / 上皮細胞 / リコンビナント蛋白 / 高分子会合体 / cDNA|
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.