Obscurin & Myofibrils in Cardiac & Skeletal Muscle

暗色素

• 批准号: 7822220
• 负责人: ROBERT J BLOCH
• 金额: $ 1.06万
• 依托单位: UNIVERSITY OF MARYLAND BALTIMORE
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-06-01 至 2010-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7822220
• 关键词: Actins; Address; Adenovirus Vector; Adult; Affect; Affinity; Ankyrins; Antibodies; Binding; Binding Sites; Biochemical; Biological Assay; C-terminal; Cardiac; Collaborations; Contractile Proteins; Coupled; Cytoskeleton; Elements; Epitopes; Gene Expression; Hand; Head; Hybrids; Hypertrophic Cardiomyopathy; Immunologic Techniques; Indium; Integral Membrane Protein; Label; Learning; Length; Link; Maps; Measurement; Membrane; Molecular Cloning; Morphogenesis; Morphology; Muscle Fibers; Muscular Dystrophies; Mutation; Myofibrillogenesis; Myofibrils; Myosin ATPase; PH Domain; Play; Proteins; Reaction; Reporting; Research Personnel; Rest; Role; Sarcomeres; Sarcoplasmic Reticulum; Signal Transduction; Site; Skeletal Muscle; Small Interfering RNA; Striated Muscles; Structure; Surface Plasmon Resonance; Testing; Thick; Thick Filament; Thin Filament; Transfection; Yeasts; connectin; knock-down; nebulin; obscurin; overexpression; programs; research study; scaffold; skeletal; uptake

DESCRIPTION (provided by applicant): In recent years, we have learned a great deal about the assembly of thick and thin filaments in striated muscle, and about the proteins that regulate the release and re-uptake of Ca2+ essential for the contractile cycle. We know much less, however, about the mechanisms that integrate thick and thin filaments into myofibrils, and about the proteins that organize the sarcoplasmic reticulum (SR) and transverse (t-) tubules so regularly around sarcomere. The recent discovery of obscurin offers new ways to address these questions. Obscurin is an approximately 800 kDa protein with structural homology to titin. It is the only protein of the titin superfamily that is concentrated, at least in part, at the periphery of sarcomeres, primarily around M-lines and Z-disks. Obscurin is composed largely of tandem Ig domains but also has signaling domains and, at its extreme COOH-terminus, a binding site for a small, integral membrane form of ankyrin 1 that is concentrated in the network SR. Given its apparent ability to concentrate at the periphery of the myofibril around M-lines and Z-disks and its high affinity for an integral protein of the SR membrane, obscurin is ideally suited to play key roles in assembling and organizing both the sarcomere and the SR. We propose to test this general hypothesis through 4 specific aims: (1) to learn how obscurin is organized with respect to key structures within sarcomeres; (2) to learn how obscurin binds to elements in the contractile apparatus; (3) to assess the effect on morphogenesis of the myofibrils and associated membranes of altering the activity of obscurin with siRNA and thru adenoviral overexpression of particular binding domains; and (4) to investigate the role of obscurin's binding to small ankyrin 1 in the assembly, organization and function of the SR. Mutations in proteins of the contractile apparatus, including some that affect the assembly or stability of contractile elements, have been implicated in hypertrophic cardiomyopathies and muscular dystrophies. The results of our experiments should reveal some of the key mechanisms involved in assembling contractile proteins into sarcomeres and in determining their association with the SR.

描述（由申请人提供）：近年来，我们了解了有关横纹肌肉中厚而薄丝的组装，以及调节收缩周期必不可少的Ca2+释放和重新摄入的蛋白质。然而，我们对将厚和薄细丝整合到肌原纤维的机制以及组织肌浆网（SR）和横向（T-）小管的蛋白质的机制少得多。最近发现的《黑素》提供了解决这些问题的新方法。 Subburin是一种大约800 kDa蛋白，与Titin结构同源。它是钛超家族的唯一蛋白质，至少部分地是在肉瘤的周围集中的，主要是在M线和Z-Disks周围。 Sigburin主要由串联Ig结构域组成，但也具有信号域，并且在其极端的COOH末端，是一个集中在网络SR中的小动脉1的小膜形式的结合位点。鉴于其明显的能力能够集中在M线和Z磁盘周围的肌原纤维周围以及对SR膜整体蛋白的高亲和力，因此Sbocburin非常适合在组装和组织肉瘤和SR中起关键作用。我们建议通过4个特定目的检验这一普遍假设：（1）了解如何与肉瘤中的关键结构进行掩盖蛋白； （2）了解掩盖蛋白如何与收缩设备中的元素结合； （3）评估对肌纤维的形态发生的影响和相关的膜，以改变sibna用siRNA的活性和特定结合结构域的腺病毒过表达的影响； （4）研究掩盖蛋白与小藻蛋白1在SR的组装，组织和功能中的结合的作用。 收缩式蛋白质中的突变与肥厚性心肌病和肌肉营养不良有关，包括影响收缩元件组装或稳定性的一些突变。我们的实验结果应揭示将收缩蛋白组装成肉瘤并确定其与SR的关联时涉及的一些关键机制。

项目成果

Na,K-ATPase in skeletal muscle: two populations of beta-spectrin control localization in the sarcolemma but not partitioning between the sarcolemma and the transverse tubules.

骨骼肌中的 Na,K-ATP 酶：β-血影蛋白的两个群体控制肌膜中的定位，但不控制肌膜和横管之间的分配。

• DOI: 10.1242/jcs.114.4.751
• 发表时间: 2001
• 期刊: Journal of cell science
• 影响因子: 4
• 作者: Williams,MW;Resneck,WG;Kaysser,T;Ursitti,JA;Birkenmeier,CS;Barker,JE;Bloch,RJ
• 通讯作者: Bloch,RJ