Role of the S100 Family of Proteins in Lens Physiology and Cataract

S100 蛋白家族在晶状体生理学和白内障中的作用

• 批准号: 10560827
• 负责人: P VASANTHA Rao
• 金额: $ 40.25万
• 依托单位: DUKE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-08-01 至 2028-07-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10560827
• 关键词: Actins; Actomyosin; Address; Adhesives; Affect; Architecture; Binding Proteins; Biochemical; Calcium; Calcium Binding; Calcium-Binding Proteins; Cataract; Cell Adhesion; Cells; Characteristics; Compensation; Crystalline Lens; Cytoskeletal Modeling; Cytoskeleton; Data; Defect; Development; Disease; EF Hand Motifs; EMS1 gene; Embryo; Epithelium; Equilibrium; Etiology; Exhibits; Family; Fiber; Fibrosis; Functional disorder; Gene Expression; Generations; Genes; Growth; Homeostasis; Human; Impairment; Integrins; Knockout Mice; Knowledge; Lens Fiber; Light; Maintenance; Malignant Neoplasms; Mechanics; Membrane; Molecular; Molecular Chaperones; Motor; Mus; Muscle; Mutation; Myosin ATPase; Myosin Type II; Neoplasm Metastasis; Neurons; Nonmuscle Myosin Type IIA; Nonmuscle Myosin Type IIB; Osmoregulation; Osmosis; Pathway interactions; Patients; Phenothiazines; Phenotype; Phosphorylation; Physiological; Physiology; Play; Polymers; Presbyopia; Prevention; Property; Proteins; Proteomics; Regulation; Retina; Role; S100 Proteins; S100A4 gene; Signal Transduction; Smooth Muscle; Stress Fibers; Testing; Tissues; Transgenic Organisms; Up-Regulation; Visual impairment; Wild Type Mouse; adducin; alpha-Crystallins; aquaporin 5; cell motility; cell type; fiber cell; interest; lens; lens intrinsic protein MP 70; lens transparency; mechanical properties; member; migration; mouse model; mutant; non-muscle myosin; novel; polymerization; radixin protein; solute; transcriptome; Actins; Actomyosin; Address; Adhesives; Affect; Architecture; Binding Proteins; Biochemical; Calcium; Calcium Binding; Calcium-Binding Proteins; Cataract; Cell Adhesion; Cells; Characteristics; Compensation; Crystalline Lens; Cytoskeletal Modeling; Cytoskeleton; Data; Defect; Development; Disease; EF Hand Motifs; EMS1 gene; Embryo; Epithelium; Equilibrium; Etiology; Exhibits; Family; Fiber; Fibrosis; Functional disorder; Gene Expression; Generations; Genes; Growth; Homeostasis; Human; Impairment; Integrins; Knockout Mice; Knowledge; Lens Fiber; Light; Maintenance; Malignant Neoplasms; Mechanics; Membrane; Molecular; Molecular Chaperones; Motor; Mus; Muscle; Mutation; Myosin ATPase; Myosin Type II; Neoplasm Metastasis; Neurons; Nonmuscle Myosin Type IIA; Nonmuscle Myosin Type IIB; Osmoregulation; Osmosis; Pathway interactions; Patients; Phenothiazines; Phenotype; Phosphorylation; Physiological; Physiology; Play; Polymers; Presbyopia; Prevention; Property; Proteins; Proteomics; Regulation; Retina; Role; S100 Proteins; S100A4 gene; Signal Transduction; Smooth Muscle; Stress Fibers; Testing; Tissues; Transgenic Organisms; Up-Regulation; Visual impairment; Wild Type Mouse; adducin; alpha-Crystallins; aquaporin 5; cell motility; cell type; fiber cell; interest; lens; lens intrinsic protein MP 70; lens transparency; mechanical properties; member; migration; mouse model; mutant; non-muscle myosin; novel; polymerization; radixin protein; solute; transcriptome

PROJECT SUMMARY The ocular lens plays a crucial role in focusing incident light on to the retina, with aberrations in lens transparency and mechanical properties leading to impairment of vision. Despite continuing effort, our understanding of the various molecular pathways governing lens cytoarchitecture, homeostasis, deformability, clarity, and the etiological mechanisms of cataract remains incomplete. We recently identified that several members of the S100 family of calcium binding proteins are abundantly expressed and exhibit distinct distribution profiles in the lens. While expression of S100A6 and S100A10 distributed to both the lens epithelium and fibers, S100A4 distributes discretely to lens fiber cells. Absence of S100A4 but not S100A6 or S100A10 leads to opalescent late-onset cataract formation in a mouse model, together with the robust upregulation of S100A5, the expression of which was otherwise undetectable in the wild type lens. Other than these new data on S100A4, we currently have no knowledge of the role played by the S100 family of proteins in lens function. S100A4 is expressed in a cell and tissue specific manner and is involved in the pathophysiology of various diseases. The physiological function of S100A4 however, is poorly understood. A well-understood molecular function of S100A4 is its interaction with non-muscle myosin II (NM II), especially NM IIA, and regulation of NM II assembly, actin polymerization, contractile characteristics, cell migration, and plasticity. NM II plays a crucial role in lens cytoarchitecture, mechanics, and function. Though NM IIA mutations are associated with cataract development in humans, little is known about regulation of NM II activity in the context of lens function. While lenses derived from mature S100A4 null mouse lenses (2 to 6 month old) remain clear and maintain normal growth and size, those from six month-old mice exhibit impairments in assembly and phosphorylation of NM IIA, polymerization of actin, and alterations in the levels of aquaporin-5, CLIC5, connexin-50, cell adhesive proteins (integrin-β1, NrCAM, ZO-1) and α-crystallin, culminating in opalescent cataract formation in eight month-old mice. Based on these preliminary and novel findings, we hypothesize that S100A4 plays a crucial role in regulating NM II assembly in the lens, and that the absence of S100A4 disrupts NM II assembly and phosphorylation, actin polymerization, mechanical properties, and osmotic homeostasis in the lens, leading to late onset cataract formation. To test this hypothesis, in three interrelated specific aims, we will investigate: 1) the mechanistic role of S100A4 in regulation of lens NM II assembly and phosphorylation, actin polymerization, cell adhesion, and lens tensile properties, 2) the disruption of osmoregulation and solute carrier transport mechanisms underlying cataractogenesis in S100A4 null lenses, and 3) the effects of rescuing expression of S100A4 in S100A4 null mouse lens fibers (using a transgenic approach) on cytoskeletal integrity and lens phenotype. These novel and interrelated studies are expected to uncover the significance of S100A4 and other members of the S100 family proteins in lens function, which are known to participate in the pathophysiology of several diseases.

项目摘要 眼镜镜头在将入射光放在视网膜上起着至关重要的作用，并且透镜透明度的畸变 和机械性能导致视力受损。尽管持续努力，我们对 各种分子途径管理晶状体细胞结构，体内稳态，可变形性，清晰度和 白内障的病因机制仍然不完整。我们最近确定了S100的几个成员 钙结合蛋白的家族是绝对表达的，并且在晶状体中表现出不同的分布谱。 而S100A6和S100A10的表达分布在镜片上皮和纤维上，而S100A4分布 离散地分配给晶状体纤维细胞。缺乏S100A4，但不存在S100A6或S100A10导致乳白色后期发作 小鼠模型中的白内障形成，以及S100A5的强大上调，其表达 否则在野生型镜头中无法检测到。除S100A4上的这些新数据外，我们目前没有 了解S100蛋白质家族在镜头功能中所起的作用。 S100A4在单元格中表达， 组织特定方式，并参与各种疾病的病理生理学。的生理功能 S100A4然而，知之甚少。 S100A4的分子函数充分理解是它与 非肌肉肌球蛋白II（NM II），尤其是NM IIA和NM II组装的调节，肌动蛋白聚合， 收缩特征，细胞迁移和可塑性。 NM II在镜头细胞结构中起着至关重要的作用， 力学和功能。尽管NM IIA突变与人类的白内障发展有关，但很少 关于在晶状体功能背景下对NM II活性的调节已知。而镜片来自成熟 S100A4无效的小鼠镜头（2至6个月大）保持清晰并保持正常生长和大小，六个 一个月大的小鼠在NM IIA的组装和磷酸化，肌动蛋白的聚合和磷酸化方面表现出损害 Aquaporin-5，Clic5，connexin-50，细胞粘合剂蛋白的水平改变（整合素-β1，NRCAM，ZO-1） 和α-晶状蛋白，在八个月大的小鼠中达到乳白色白内障形成。基于这些 初步和新颖的发现，我们假设S100A4在调节NM II组装中起着至关重要的作用 镜头，缺乏S100A4会破坏NM II组装和磷酸化，肌动蛋白聚合， 机械性能和镜片中的渗透稳态，导致迟到性白内障的形成。测试这个 假设，在三个相互关联的特定目的中，我们将研究：1）S100A4在调节中的机械作用 镜头NM II组装和磷酸化，肌动蛋白聚合，细胞粘合剂和透镜拉伸特性的含量，2） 渗透调节和可溶性载体传输机制的破坏在白内术中的基础发生 S100A4无效镜头和3）在S100A4中拯救S100A4表达的效果（使用 转基因方法）关于细胞骨架完整性和镜头表型。这些小说和相互关联的研究是 预计将发现S100A4和S100家族蛋白在晶状体功能中的重要性， 已知会参与几种疾病的病理生理学。