Strucutre of the UNC-45 Chaperone and its Interaction with Skeletal Muscle Myosin

UNC-45 伴侣的结构及其与骨骼肌肌球蛋白的相互作用

• 批准号: 7870691
• 负责人: Sanford I Bernstein
• 金额: $ 1.49万
• 依托单位: SAN DIEGO STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-07-14 至 2009-10-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7870691
• 关键词: Binding; Complex; Computer Analysis; Contractile Proteins; Crystallization; Crystallography; Disease; Docking; Drosophila genus; Electron Microscopy; Elements; Escherichia coli; Goals; Heating; Image; Image Analysis; Mammals; Molecular Chaperones; Molecular Motors; Molecular Structure; Muscle; Muscle Development; Muscle function; Myofibrils; Myopathy; Myosin ATPase; Negative Staining; Nucleotides; Play; Production; Protein Analysis; Protein Denaturation; Proteins; Qualifying; Research; Resistance; Resolution; Role; S-1 Antimetabolite agent; Skeletal Muscle; Skeletal Muscle Myosins; Stress; Structure; Tertiary Protein Structure; Testing; analog; fungus; insight; member; muscle stress; particle; programs; protein aggregation; protein folding; public health relevance

DESCRIPTION (provided by applicant): We propose to study the structure and mechanism of action of the UNC-45 molecular chaperone, a myosin- affiliated "UCS domain" protein. Molecular chaperones play key roles in muscle development and function by aiding protein folding and inhibiting protein denaturation and aggregation. We have demonstrated that UNC-45 is critical for skeletal muscle myosin accumulation and myofibril assembly and that it interacts with myosin to protect it from heat-induced aggregation. However, the structure of UNC-45, its mode of interaction with myosin and its roles in skeletal muscle disease are largely unexplored. Our goal is to define the molecular structure of Drosophila UNC-45 and to study its physical interaction with myosin. We will test the hypotheses that 1) ATP binding, which enhances UNC-45 chaperone function, causes structural elements of the protein to undergo conformational change and 2) the UCS domain of UNC-45 interacts with myosin. To this end, we will examine UNC-45 in the apo- and nucleotide-bound states at atomic-level resolution by crystallization, x-ray diffraction and computational analysis. This will be the first high-resolution structure of a UCS domain protein, a class of myosin-associated proteins found in fungi through mammals. We will also image UNC-45 complexed with myosin S-1 by negative staining, electron microscopy and single particle image analysis followed by docking the crystal structures into class averaged projections. This research program will take advantage of our expertise in contractile protein analysis and the capabilities of highly qualified collaborators. Our studies will elucidate the structure of UNC-45, provide an understanding of its interaction with ATP and define ATP- induced conformational changes. Further, our efforts will yield insight into UNC-45's physical interaction with the myosin substrate, which is critical to myofibril assembly and resistance to stress. PUBLIC HEALTH RELEVANCE. The UNC-45 chaperone is critical for the functional integrity of myosin, the molecular motor of muscle. We will study the structure of the UNC-45 chaperone and its interaction with its myosin target. Our efforts will elucidate the mechanism of action of UNC-45 and provide insight into how it functions in normal muscle as well as an understanding of its role during muscle stress.

描述（由申请人提供）：我们建议研究UNC-45分子伴侣蛋白的UNC-45分子伴侣的作用结构和机理。分子伴侣通过帮助蛋白质折叠并抑制蛋白质变性和聚集在肌肉发育和功能中起关键作用。我们已经证明，UNC-45对于骨骼肌肌球蛋白积累和肌原纤维组件至关重要，并且它与肌球蛋白相互作用以保护其免受热诱导的聚集。然而，UNC-45的结构，其与肌球蛋白的相互作用及其在骨骼肌疾病中的作用在很大程度上没有探索。我们的目标是定义果蝇UNC-45的分子结构，并研究其与肌球蛋白的物理相互作用。我们将检验以下假设：1）ATP结合增强了UNC-45伴侣函数，导致蛋白质的结构元素发生构象变化，而2）UNC-45的UCS结构域与肌球蛋白相互作用。为此，我们将通过结晶，X射线衍射和计算分析在原子级分辨率下以原子级和核苷酸结合的状态检查UNC-45。这将是UCS结构蛋白的第一个高分辨率结构，UCS结构蛋白是通过哺乳动物在真菌中发现的一类肌球蛋白相关蛋白。我们还将通过负染色，电子显微镜和单个粒子图像分析与肌球蛋白S-1相结合的UNC-45，然后将晶体结构停靠到类平均投影中。该研究计划将利用我们在收缩蛋白分析方面的专业知识和高素质合作者的能力。我们的研究将阐明UNC-45的结构，从而了解其与ATP的相互作用并定义ATP诱导的构象变化。此外，我们的努力将洞悉UNC-45与肌球蛋白底物的物理相互作用，这对于肌原纤维组装至关重要，并且对压力的抵抗力至关重要。公共卫生相关性。 UNC-45伴侣伴侣对肌球蛋白的功能完整性至关重要，肌球蛋白的分子运动的肌肉运动。我们将研究UNC-45伴侣的结构及其与肌球蛋白靶标的相互作用。我们的努力将阐明UNC-45的作用机理，并提供有关其在正常肌肉中的功能以及对其在肌肉压力中的作用的了解。