CRYSTAL STRUCTURE DETERMINATION OF COLLAGEN-RELATED STRUCTURES

该子项目是利用NIH/NCRR资助的中心赠款提供的资源的许多研究子项目之一。子项目和研究者（PI）可能从另一个NIH来源获得主要资金，因此可以在其他CRISP条目中表示。所列机构为中心机构，不一定为研究者机构。IV型胶原是所有后生动物基底膜的主要结构蛋白组分。它含有一个大的C-末端球状结构域（NC 1结构域），通过该结构域，三条链以链特异性方式缔合形成三螺旋原聚体。这也在细胞外基质中IV型胶原的超分子组装中起主要作用。组织特异性Ⅳ型胶原原体存在于哺乳动物中，与？1.？1.？2原聚体是无处不在的和？三个？4.什么？肾内5个原聚体。我们实验室在该项目中的长期兴趣是确定六聚体形式的NC 1结构域的晶体结构以及它们的单体组分，以了解链特异性组装IV型胶原。这些结构将对理解IV型胶原在组织发育中的作用具有重要意义，更具体地说，肾脏。至少有两种肾脏疾病，即Alport综合征和Goodpasture综合征，与IV型胶原蛋白直接相关。分子结构[？三个？4.什么？5]2然后呢？3个单体在理解Goodpasture综合征发病机制的分子基础方面尤其重要。这是一种自身免疫性疾病，其中的抗体专门针对？3 NC 1结构域在单体中，但当它是[？三个？四个？5]2六聚体测定了NC 1六聚体的第一级晶体结构。1.？1.？2]2使用在SSRL收集的Br-MAD数据。我们还收集了关于？2、？3个单体晶体，其结构不能通过使用六聚体的单体模型的分子置换法来解决。接下来，我们将尝试使用Se或Br作为异常散射体通过MAD来解决这些结构。我们还获得了弱衍射晶体[？三个？4.什么？5]2 NC 1六聚体，无法使用内部来源进行表征。

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. Type IV collagen is a major structural protein component of basement membrane of all metazoan. It contains a large C-terminal globular domain (NC1 domain) by which three chains associate to form triple helical protomers in a chain specific manner. This also plays a major role in the supramolecular assembly of collagen type IV in the extracellular matrix. Tissue specific protomer types of collagen IV exist in mammals, with ?1.?1.?2 protomer being ubiquitous and ?3.?4.?5 protomer in kidney. The long standing interest of our lab in this project is to determine the crystal structures of NC1 domains in hexameric forms as well as their monomeric components to understand the chain specific assembly type IV collagen. These structures will have strong implications in understanding the role of type IV collagen in tissue development, more specifically, kidney. At least two kidney diseases, namely Alport¿¿s syndrome and Goodpasture¿¿s syndrome, are directly linked to type IV collagen. The molecular structures of [?3.?4.?5]2 and ?3 monomer are especially crucial in understanding the molecular basis for the pathogenesis of Goodpasture syndrome. This is an autoimmune disease in which the antibodies specifically target ?3 NC1 domain in the monomer, but not when it is a part of [?3.?4.?5]2 hexamer. We have determined the first crystal structure of NC1 hexamer, [?1.?1.?2]2 using Br-MAD data collected at SSRL. We have also collected data on ?2 and ?3 monomer crystals, whose structures could not be solved by molecular replacement method using the monomer models from the hexamer. Next, we would attempt to solve these structures by MAD using Se or Br as anomalous scatterer. We have also obtained weakly diffracting crystals of [?3.?4.?5]2 NC1 hexamer, which could not be characterized using the in-house source.