Collagen XVIII/BP180:Structural and Functional Studies

描述（由申请人提供）： BP 180是表皮锚定复合物的关键组分，其功能是维持表皮与基底膜的粘附。BP 180已被发现在几种起泡性皮肤病中存在遗传缺陷或被免疫系统靶向。结构研究表明，BP 180是一种II型跨膜蛋白，具有长的羧基端胶原结构域，该结构域突出到表皮半桥粒下方的细胞外区域。这项资助的第一个具体目标是解决关于BP 180胞外结构域的重要问题，该结构域以中断的胶原三螺旋的形式存在。他们计划确定BP 180三聚体组装所必需的蛋白质片段，并研究与基底膜区遗传性疾病相关的BP 180突变的结构后果。第二个具体目标是鉴定BP 180的细胞外配体。解决这个问题的一种方法涉及分析BP 180转导的细胞的细胞-基质附着特性的改变。第二种方法涉及使用共免疫沉淀方案测定蛋白质-蛋白质相互作用。 拟议的研究项目代表了一个多层次的方法来研究参与维持皮肤基底膜区的完整性的分子相互作用。在获奖期间，候选人将能够扩大她在细胞和分子生物学，生物化学和免疫学领域的研究经验。候选人的长期目标是继续在学术环境中对其他胶原蛋白及其突变进行生物化学和分子生物学研究。

DESCRIPTION (provided by applicant): BP180 is a key component of the epidermal anchoring complex and functions to maintain the adherence of the epidermis to the basement membrane. BP180 has been found to be genetically defective or targeted by the immune system in several blistering skin diseases. Structural studies have revealed that BP180 is a type II transmembrane protein with a long carboxy-terrninal collagenous domain that projects into the extracellular region beneath the epidermal hemidesmosome. The first specific aim of this grant addresses important questions regarding the structure of the BP180 extracellular domain, which exists in the form of an interrupted collagen triple helix. They plan to define the protein segments that are essential for the assembly of the BP180 trimer, and to investigate the structural consequences of BP180 mutations that are associated with inherited disorders of the basement membrane zone. The second specific aim is directed toward identifying the extracellular ligand(s) for BP180. One approach to this problem involves analyzing BP180-transduced cells for alterations in cell-matrix attachment properties. A second approach involves assaying protein-protein interactions using a co-immuno-precipitation protocol. The proposed research project represents a multi-level approach to the study of molecular interactions involved in maintaining the integrity of the cutaneous basement membrane zone. During the award period, the candidate will be able to broaden her research experience in the areas of cell and molecular biology, biochemistry and immunology. The candidate's long-range goals are to continue biochemical and molecular biological studies of other collagen proteins and their mutations in an academic setting.