AGGRECAN STRUCTURAL VARIANTS--MATRIX AND OSTEOARTHRITIS

Aggrecan 结构变异——基质和骨关节炎

• 批准号: 6043130
• 负责人: KURT J. DOEGE
• 金额: $ 10.44万
• 依托单位: UNIVERSITY OF SOUTH FLORIDA
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-08-01 至 2001-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6043130
• 关键词: articular cartilage; biological polymorphism; cell line; chondroitin sulfates; extracellular matrix; genetic polymorphism; genetic susceptibility; mechanical stress; microscopy; osteoarthritis; pathologic process; protein structure function; proteoglycan; tissue /cell culture; transfection

DESCRIPTION (Adapted from the Applicant's Abstract): This proposal is designed to study the relationship between the structure of aggrecan and its functional role in the matrix of articular cartilage. Aggrecan is a proteoglycan whose core protein bears over 100 chondroitin sulfate chains, and which assembles into large aggregates that create a strong swelling pressure in the tissue and help it to serve as a cushioning material within articulating joints. This application is based on the recent observation that the human aggrecan core protein exhibits a unique degree of polymorphism, which produces core proteins of different lengths in different individuals, and results in aggrecan molecules whose potential number of chondroitin sulfate attachment sites may vary by up to 30%. Such structural differences could potentially influence the function of the molecule, and this scenario is made more intriguing by the observation that one of the polymorphic aggrecan alleles is preferentially associated with bilateral osteoarthritis of the hand. To study the relationship between the variant polymorphic chondroitin sulfate-attachment regions and cartilage function, an immortalized chondrocyte cell line will be stably transfected with mini-gene constructs in which the polymorphic region is flanked by aggrecan G1 and G3 domains. Different cells lines exhibiting high and low levels of recombinant expression will be analyzed to study variations that may occur in the size, type of sulfation and position of substitution of the chondroitin sulfate chains. The nature of the matrix produced by the recombinant-expressing cell lines will also be studied in an agarose culture system. The structure of the resulting matrix will be assessed by microscopy techniques, and its function by biomechanical testing. The resulting data will be used to test the hypothesis that the different aggrecan alleles can affect the functional properties of the cartilage, and will establish a basis for future study of their role in the development of osteoarthritis.

描述(改编自申请者摘要)：本建议书 旨在研究聚集素的结构与其结构之间的关系 关节软骨基质的功能作用。阿格利坎是一家 蛋白多糖，其核心蛋白含有100多条硫酸软骨素链， 它们聚集成大团聚体，形成强烈的肿胀 对组织施加压力，帮助它在体内起缓冲材料的作用 关节连接。这项申请是基于最近的观察结果 人类聚集素核心蛋白表现出独特程度的 多态，在不同的基因中产生不同长度的核心蛋白 个体，并导致聚集素分子的潜在数量 硫酸软骨素的附着位置可能有高达30%的差异。这样的结构 差异可能会潜在地影响分子的功能，并且 这种情况更耐人寻味的是，观察到 Aggrecan等位基因的多态与双侧优先相关 手部的骨关节炎。研究变种之间的关系 硫酸软骨素附着区的多态与软骨功能 永生化软骨细胞系将稳定转染 其中多态区域被aggrecan包围的微型基因结构 G1和G3结构域。不同的细胞系表现出高水平和低水平的 将对重组表达进行分析以研究可能发生的变异 在硫化的大小、类型和取代位置中 硫酸软骨素链。生成的矩阵的性质 重组表达细胞系也将在琼脂糖培养中进行研究。 系统。结果矩阵的结构将通过以下方式进行评估 显微技术及其生物力学测试的功能。这个 所得到的数据将被用来检验这样的假设，即不同的 Aggrecan等位基因可以影响软骨的功能特性，并且 将为今后研究它们在发展中的作用奠定基础 骨性关节炎。