Regulation of chondrocytes by extracellular matrix protein.

细胞外基质蛋白对软骨细胞的调节。

基本信息

批准号：
7998204
负责人：
Steven B Abramson
金额：
$ 32.3万
依托单位：
NEW YORK UNIVERSITY SCHOOL OF MEDICINE
依托单位国家：
美国
项目类别：
财政年份：
2009
资助国家：
美国
起止时间：
2009-04-01 至 2013-12-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7998204
关键词：
Address Adult Affect Age Area Binding Proteins Biological Process Bone Development Cartilage Cartilage Diseases Cell Culture Techniques Cell Surface Receptors Cells Characteristics Chondrocytes Collagen Collagen Type II Complementary DNA Complex Degenerative polyarthritis Deterioration Dinoprostone Disease Disease Progression Embryo Epiphysial cartilage Event Extracellular Matrix Proteins Gene Expression Genes Growth Health Histologic Human Hybrids Hypertrophy Immunoprecipitation In Vitro Joints Knockout Mice Lead Length Lesion Limb structure Link Matrix Metalloproteinases Medial Mediating Metabolism Modeling Molecular Mus Neurons Operative Surgical Procedures Osteoarthrosis Deformans Osteocalcin Osteogenesis Pathogenesis Pathway interactions Peptide Hydrolases Peptides Phenotype Plasmin Play Population Process Property Protein Family Proteins Proteomics Public Health Regulation Relative (related person)Research Proposals Rodent Role Skeletal Development Specimen Subgroup Technology Testing Tissues Transgenic Organisms Yeasts articular cartilage base cartilage repair collagenase 3 design disability improved in vivo insight knockout gene loss of function mature animal member mineralization mouse model novel novel strategies overexpression premature prevent protein protein interaction receptor research study tibia yeast two hybrid system

项目摘要

DESCRIPTION (provided by applicant): F-spondin is a member of a family of proteins that collectively belong to a subgroup of TSR (thrombospondin) type I class molecules. We have discovered that F-spondin expression is significantly increased in osteoarthritic cartilage as well as in rodent meniscectomy models of OA. Preliminary studies indicate that F-spondin has significant effects on human chondrocyte metabolism and is also expressed in the hypertrophic regions of embryonic growth plates where it acts to regulate mineralization and endochondral bone formation. This proposal is designed to characterize the functional effects of F-spondin, which have major and previously unrecognized implications for the progression of OA. We will test two central hypotheses: 1) F-spondin modulates collagen degradation via unrecognized pathways that include activation of TGF-¿ and induction of MMPs and 2) F-spondin induces hypertrophic differentiation of articular chondrocytes and plays an essential role in the regulation of mineralization and endochondral bone formation. The specific aims designed to test these hypotheses are as follows: In SPECIFIC AIM 1 we will investigate the effects of F-spondin on the regulation of hypertrophy and mineralizing activity in human articular chondrocytes in vitro culture models. Cartilage specimens will be examined histologically to investigate the link between F-spondin and other characteristic hypertrophic/ossification markers of OA chondrocytes. In SPECIFIC AIM 2 we will investigate the molecular mechanism(s) of F-spondin-mediated collagen degradation in OA cartilage. Explant or cell cultures will be used to a) identify MMPs induced by F- spondin and examine their role in F-spondin-mediated collagen degradation b) establish the role of TGF-¿ in modulation of F-spondin functions and c) compare functional activity of the full length F-spondin molecule relative to its proteolytic fragments. In SPECIFIC AIM 3 we will identify and characterize the interacting proteins of F-spondin. a) investigate the interaction of F-spondin with the Latency-associated peptide (LAP) of the latent TGF-¿ complex and b) utilize yeast 2 hybrid and proteomic technologies to identify novel F-spondin binding proteins (proteases, receptors, matrix molecules) that may regulate its activity in articular cartilage. In SPECIFIC AIM 4 we will investigate the expression and function of F-spondin in cartilage in vivo. We will investigate F-spondin expression in cartilage in vivo i) during endochondral bone development and ii) in the mouse meniscectomy model of OA. We will generate an F-spondin knockout mouse and characterize the changes in cartilage phenotype during endochondral bone development and OA disease progression. Understanding the regulation of chondrocyte functions by F-spondin could lead to novel strategies for cartilage repair and disease modifying treatments for osteoarthritis. PUBLIC HEALTH RELEVANCE: Osteoarthritis affects more than 20% of the population over age 60 and for millions of people is a significant cause of disability. This research proposal will focus on a protein, F-spondin, never before described in cartilage, which regulates processes that are important in joint deterioration in osteoarthritis. The proposed experiments are designed to identify previously unrecognized pathological events that lead to new treatments for osteoarthritis, which prevent the progression of disease, reduce the likelihood of disability and improve the public health.

描述（由申请人提供）：F-spondin 是蛋白质家族的成员，这些蛋白质共同属于 TSR（血小板反应蛋白）I 型分子亚组。我们发现 F-spondin 表达在骨关节炎软骨中也显着增加。初步研究表明，F-spondin 对人类软骨细胞代谢有显着影响，并且在肥大区域也有表达。该提案旨在描述 F-spondin 的功能作用，其对 OA 的进展具有重大且先前未被认识的影响：1。 ) F-spondin 通过未识别的途径（包括 TGF-¿ 的激活）调节胶原蛋白降解2) F-spondin 诱导关节软骨细胞的肥大分化，并在矿化和软骨内骨形成的调节中发挥重要作用。旨在检验这些假设的具体目标如下：在具体目标 1 中，我们将进行研究。将通过组织学方法检查 F-spondin 对体外培养模型中人关节软骨细胞肥大和矿化活性的调节作用。为了研究 F-spondin 与 OA 软骨细胞的其他特征性肥大/骨化标记物之间的联系，在 SPECIFIC AIM 2 中，我们将研究 OA 外植体或细胞培养物中 F-spondin 介导的胶原蛋白降解的分子机制。用于 a) 识别 F-spondin 诱导的 MMP 并检查其在 F-spondin 介导的胶原降解中的作用 b) 确定 TGF-¿ c) 比较全长 F-spondin 分子与其蛋白水解片段的功能活性在 SPECIFIC AIM 3 中，我们将鉴定和表征 F-spondin 的相互作用蛋白 a) 研究的相互作用。 F-spondin 与潜在 TGF-¿ 的潜伏相关肽 (LAP) b) 利用酵母 2 杂交和蛋白质组学技术来鉴定新型 F-spondin 结合蛋白（蛋白酶、受体、基质分子），这些蛋白可能调节其在关节软骨中的活性。在 SPECIFIC AIM 4 中，我们将研究 F-spondin 的表达和功能。我们将研究体内软骨中的 F-spondin i) 软骨内骨发育期间和 ii) OA 小鼠半月板切除模型中的表达。我们将培育 F-spondin 敲除小鼠，并表征软骨内骨发育和 OA 疾病进展过程中软骨表型的变化。了解 F-spondin 对软骨细胞功能的调节可能会产生软骨修复和骨关节炎疾病修饰治疗的新策略。公共卫生相关性：骨关节炎影响超过 20% 的 60 岁以上人口，并且是数百万人残疾的重要原因。该研究将重点关注软骨中从未被描述过的蛋白质 F-spondin，它调节对骨关节炎关节恶化至关重要的过程。拟议的实验旨在识别以前未被识别的病理事件，这些事件会导致骨关节炎的新治疗方法，从而预防骨关节炎的发生。疾病进展，减少残疾的可能性并改善公众健康。