Collagen-Annexin Interactions in Tissue Mineralization

组织矿化中胶原蛋白-膜联蛋白的相互作用

• 批准号: 7085566
• 负责人: THORSTEN KIRSCH
• 金额: $ 25.09万
• 依托单位: UNIVERSITY OF MARYLAND BALTIMORE
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-07-01 至 2008-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7085566
• 关键词: SDS polyacrylamide gel electrophoresis; annexins; apoptosis; calcium channel; calcium flux; cell differentiation; cell growth regulation; chick embryo; chondrocytes; collagen; flow cytometry; fluorescence microscopy; genetically modified animals; immunoprecipitation; in situ hybridization; infrared spectrometry; interferometry; laboratory mouse; microcalorimetry; normal ossification; polymerase chain reaction; protein protein interaction; protein structure function; terminal nick end labeling; tissue /cell culture; western blottings

Our long term goal of this study is to elucidate the roles of annexins II, V and VI and the interactions between annexin V and types II and X collagen in terminal differentiation events of chondrocytes. Terminal differentiation of growth plate chondrocytes consists of a series of events including mineralization and programmed cell death (apoptosis). These events play a crucial role during normal bone formation. If they, however, occur during pathological conditions, such as osteoarthritis, they will lead to cartilage destruction. Thus, an understanding of the cellular mechanisms controlling terminal differentiation of chondrocytes is of great importance. Major advances during the last funding period led to the following three new hypotheses which will be tested in the current proposal: (i) annexin channel formation in the plasma membrane of growth plate chondrocytes and annexin V channel activation by types II and X :ollagen lead to calcium influx into growth plate chondrocytes and alteration of calcium homeostasis; (ii) optimal annexin channel formation and annexin V/collagen interactions require the interactions between annexin II, V and VI; (iii) annexin-mediated alteration of calcium homeostasis regulates terminal differentiation events of growth plate chondrocytes. These hypotheses will be addressed through the following specific aims: 1. We will determine the function of annexin II, V and VI channel formation and annexin V/collagen interactions in alteration of calcium homeostasis in growth plate chondrocytes and test whether annexins through binding to collagen and cytoskeleton act as mechanosensors in these cells. 2. We will determine the interactions between annexin II, V and VI as a possible major regulator of annexin channel formation and annexin V/collagen interactions. 3. We will determine the regulatory roles of annexins and annexin V/collagen interactions in terminal differentiation events including mineralization and apoptosis of growth plate chondrocytes.This study relates directly to the mechanisms which control terminal differentiation of chondrocytes and investigates a novel mechanism regulating calcium homeostasis in skeletal cells.Thus, this proposal will not only greatly advance our understanding of how terminal differentiation events are regulated, but it might also provide novel therapeutic targets to prevent terminal differentiation events during patholoaical conditions.

我们这项研究的长期目标是阐明膜联蛋白 II、V 和 VI 的作用以及膜联蛋白 V 与 II 型和 X 型胶原在软骨细胞终末分化事件中的相互作用。生长板软骨细胞的终末分化由一系列事件组成，包括矿化和程​​序性细胞死亡（细胞凋亡）。这些事件在正常骨形成过程中起着至关重要的作用。然而，如果它们发生在病理条件下，例如骨关节炎，则会导致软骨破坏。因此，了解控制软骨细胞终末分化的细胞机制非常重要。上一个资助期间的重大进展产生了以下三个新假设，这些假设将在当前提案中进行测试：（i）生长板软骨细胞质膜中的膜联蛋白通道形成以及 II 型和 X 型膜联蛋白 V 通道激活 ：胶原蛋白导致钙流入生长板软骨细胞并改变钙稳态； (ii) 最佳膜联蛋白通道形成和膜联蛋白 V/胶原相互作用需要膜联蛋白 II、V 和 VI 之间的相互作用； (iii)膜联蛋白介导的钙稳态改变调节生长板软骨细胞的终末分化事件。这些假设将通过以下具体目标得到解决： 1. 我们将确定膜联蛋白 II、V 和 VI 通道形成的功能以及膜联蛋白 V/胶原蛋白相互作用在改变生长板软骨细胞钙稳态中的功能，并测试膜联蛋白是否通过与胶原蛋白结合细胞骨架在这些细胞中充当机械传感器。 2. 我们将确定膜联蛋白 II、V 和 VI 之间的相互作用作为膜联蛋白通道形成和膜联蛋白 V/胶原蛋白相互作用的可能主要调节因子。 3.我们将确定监管角色 膜联蛋白和膜联蛋白 V/胶原在终末分化事件中的相互作用，包括生长板软骨细胞的矿化和凋亡。本研究直接涉及控制软骨细胞终末分化的机制，并研究调节骨骼细胞中钙稳态的新机制。因此，本研究不仅将极大地增进我们对终末分化事件如何调节的理解，而且还可能提供新的治疗靶点来预防病理条件下的终末分化事件。