THE MOLECULAR STRUCTURE OF COLLAGEN TYPES I AND II

这个子项目是许多研究子项目中的一个 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得了主要资金， 因此可以在其他CRISP条目中表示。所列机构为 研究中心，而研究中心不一定是研究者所在的机构。 纤维胶原蛋白是人类已知的最重要的结构蛋白质之一，形成各种器官组织以及脉管系统、皮肤、骨骼和软骨的结构基础。主要的胶原类型，纤维形式，表现为支架，一个三维网络与（迄今为止）结构不明确的结合和识别位点的许多细胞外基质大分子。I型胶原蛋白是动物界中最丰富的胶原蛋白，也是大多数哺乳动物结缔组织的关键部分。II型胶原蛋白是哺乳动物软骨、椎间盘和其他组织在其发育过程中的重要组成部分，但关于这两种胶原蛋白类型在亚纤维水平上的组织结构知之甚少。幸运的是，在大鼠尾腱和七鳃鳗组织中发现的纤维状I型和II型胶原蛋白有些结晶，这一特性将允许通过X射线纤维衍射研究胶原蛋白分子结构。从大鼠尾腱和几个七鳃鳗组织中获得的衍射图案包含关于胶原蛋白链的亚纤维组织的信息。以前，这些数据（在BioCAT收集）被用来解决I型胶原蛋白的3D结构到1.1 nm，揭示了胶原酶（和其他EM活性分子）结合胶原蛋白链的机制的重要限制。冷冻技术的后续发展将用于扩展该结构的分辨率，同时使用BioCAT光束线的新开发的微焦点功能收集II型胶原蛋白的数据，以类似地使用MIR解决其结构。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The fibrous collagens are amongst the most important structural proteins known to man, forming the structural basis of various organ tissues as well as vasculature, skin, bones and cartilage. The major collagen types, the fibrillar forms, behave as scaffolding, a three-dimensional network with (as yet) structurally ill-defined binding and recognition sites for numerous extracellular matrix macromolecules. Type I collagen is the single most abundant collagen in the animal kingdom and a critical part of most mammalian connective tissues. Type II collagen is a crucial component of mammalian cartilage, inter-vertebral discs and other tissues during their development, yet relatively little is known concerning the organization of these two collagen types at the sub-fibrillar level. Fortunately, the fibrillar type I and II collagen's found within rat tail tendon and in lamprey tissues are somewhat crystalline, a property that will allow an investigation of collagen molecular structure through X-ray fiber diffraction. Diffraction patterns obtained from both rat tail tendon and several lamprey tissues contain information regarding the sub-fibrillar organization of collagen chains. Previously, such data (collected at BioCAT) was used to solve the 3D structure of type I collagen to 1.1 nm, revealing important constraints on the mechanism by which collagenase (and other EM active molecules) bind the collagen chains. Subsequent developments in cryo-freezing techniques will be used to extend the resolution of this structure, whilst data is collected for type II collagen using the newly developed micro-focus capabilities of the BioCAT beamline to similarly solve its structure using MIR.