Characterization of purified myocilin : glaucoma as a protein misfolding disease DEIA Supplement

纯化肌纤蛋白的表征：青光眼作为一种蛋白质错误折叠疾病 DEIA 补充

• 批准号: 10789112
• 负责人: Raquel L Lieberman
• 金额: $ 38.46万
• 依托单位: GEORGIA INSTITUTE OF TECHNOLOGY
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-03-01 至 2026-02-28
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10789112
• 关键词: Academia; Acceleration; Affect; Alleles; Alzheimer' s Disease; Amyloid; Amyloidosis; Amyotrophic Lateral Sclerosis; Anatomy; Anterior eyeball segment structure; Aqueous Humor; Blindness; Cell Death; Cells; Comprehension; Deuterium; Diagnosis; Disease; Drainage procedure; Endoplasmic Reticulum; Extracellular Matrix; Extracellular Matrix Proteins; Eye; Eye diseases; Foundations; Functional disorder; Funding; Glaucoma; Goals; Homeostasis; Horns; Hydrogen; Industry; Inherited; Knowledge; Lead; Length; Liquid substance; Mass Spectrum Analysis; Medical; Methods; Modality; Molecular; Molecular Chaperones; Mutation; Nerve Degeneration; Nuclear Magnetic Resonance; Open-Angle Glaucoma; Outcome; Pathogenesis; Pathogenicity; Pathway interactions; Patients; Physiologic Intraocular Pressure; Physiology; Play; Process; Proteins; Relaxation; Retina; Role; Structure; Therapeutic; Tissues; Trabecular meshwork structure; Variant; amyloid formation; blind; cytotoxicity; early onset; gain of function; infancy; multidisciplinary; mutant; myocilin; novel; novel therapeutics; olfactomedin; pressure; protein misfolding; proteostasis; solid state nuclear magnetic resonance; superoxide dismutase 1; symptom treatment; timeline

Glaucoma, a leading cause of blindness worldwide (70 million patients), is managed medically by treating the symptom of increased intraocular pressure (IOP), but 10% of patients still go blind. IOP is controlled in the anterior segment of the eye, which contains the trabecular meshwork (TM) extracellular matrix, the anatomical pathway for drainage of aqueous humor fluid. The TM tissue is diseased in most forms of glaucoma; loss of TM homeostasis leads to elevated IOP. Hereditary open angle glaucoma, affecting ~3 million young patients, is caused by mutations in myocilin, a protein highly expressed in the TM. Since 3/2011, studies funded from R01EY021205 have changed the paradigm for anti-glaucoma therapeutics by laying the molecular foundation for approaches that target the disease process, which are now being pursued in academia and industry. Studies from R01EY021205 have clarified molecular details of the toxic gain-of-function pathogenic mechanism in which mutant myocilin accumulates in the endoplasmic reticulum (ER) of TM cells, leading to TM cell death and an accelerated timeline for vision loss. Studies from R01EY021205 (a) contributed fundamental knowledge of myocilin structure, (b) discovered a counter-productive interaction between myocilin and the ER-resident Hsp90 chaperone Grp94, and (c) characterized myocilin misfolding as amyloid. Wild-type and many different myocilin variants harbor a misfolding propensity; thus, proteostasis issues identified in familial myocilin-associated glaucoma are likely at play in many more patients. Amyloid formation by myocilin places glaucoma alongside more well-studied amyloid diseases like Alzheimer and SOD-1 dependent amyotrophic lateral sclerosis, yet comprehension of the role of amyloid in glaucoma is in its infancy. The current objective is to better understand molecular aspects of myocilin fibrilization, focused on the relevant olfactomedin (OLF) domain. The multidisciplinary team led by Raquel Lieberman will (a) clarify initiation of aggregation by studying solution structures of wild-type and selected OLF variants, as well as corresponding multi-length scale dynamics, using hydrogen-deuterium exchange mass spectrometry and nuclear magnetic resonance (NMR) structure and relaxation methods (Wade Van Horn, Co- I) (b) compare the end-point structures of selected OLF aggregates to known amyloids by solid state NMR (Anant Paravastu, Co-I) and evaluate cytotoxicity of intermediate aggregates and (c) evaluate common allele full-length myocilin variants for experimental hallmarks of pathogenicity. The expected outcome is a better understanding of the myocilin misfolding process at the molecular level, including molecular determinants of pathogenicity, to enable novel modalities for studying, diagnosing, and treating myocilin-associated glaucoma. More broadly, continued structure/dysfunction studies of myocilin will not only contribute to an understanding of glaucoma and its role in the TM, but will also extend comprehension of the many other OLF domains, which are implicated broadly in physiology and diseases.

青光眼是全世界失明的主要原因（7000万患者），其医学管理方法是治疗