Biomolecular Mechanics of Collagen Monomers And Fibrils

胶原单体和原纤维的生物分子力学

• 批准号: 6418426
• 负责人: CHARLOTTE L PHILLIPS
• 金额: $ 17万
• 依托单位: UNIVERSITY OF MISSOURI-COLUMBIA
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-03-08 至 2003-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6418426
• 关键词: animal tissue; aorta; atomic force microscopy; biomechanics; cell components; collagen; connective tissue; covalent bond; crosslink; disease /disorder model; extracellular matrix; gene mutation; intermolecular interaction; monomer; osteogenesis imperfecta; protein protein interaction; protein structure function; skin; tendons; tensile strength

DESCRIPTION (provided by applicant): Biomechanical stability and strength of connective tissues have long been attributed to covalent intermolecular crosslinks between collagen monomers. Type I collagen, a major component of bone, tendon, skin, and the vasculature, is normally heterotrimeric, consisting of two al (I) chains and a single a2(I) chain, [al(I)2a2(I)]. However, type I collagen in oim mice is exclusively composed of al(I) homotrimers, [al(I)3] (result of a null mutation in the a2(I) gene). Oim mice are a superb model system for examining the functional necessity of the a2(I) chain. We hypothesize that the absence of a2(I) chains perturbs collagen fibril formation, collagen-collagen interactions, and intra- and inter-molecular crosslinking, compromising the structural and biomechanical integrity of connective tissues. In vivo studies using oim mice demonstrate that the presence of type I collagen homotrimers significantly decreases the biomechanical integrity of bone, tendon, skin and aorta. Further analyses using oim mice suggest non-covalent collagen intra- and intermolecular interactions and organization maybe the critical factors regulating mechanical integrity rather than collagen crosslinking. These results question the dogma that covalent intermolecular crosslinks between collagen monomers are the principal determinants of stability and biomechanical integrity of the fibrillar architecture, and compel us to consider other forces and interactions, such as the inherent mechanical properties of individual collagen monomers and non-covalent protein-protein interactions. Recent advances in the application of atomic force microscopy now make it possible to analyze inherent mechanical properties of single biomolecules and molecule-molecule interactions. We propose to use atomic force microscopy to define the role of a2(I) chains 1) in the inherent mechanical integrity of collagen monomers, 2) in non-covalent collagen-collagen interactions, and 3) in the inherent mechanical integrity of collagen fibrils, as well as provide a powerful new tool for defining and understanding the pathogenesis of fibrillar collagen mutations and other extracellular matrix components and their role in connective tissue disease.

描述（由申请人提供）：生物力学稳定性和强度