Modeling and mechanistic investigation of a novel dry AMD mouse model with CLIC4 deleted in RPE

摘要 老年性黄斑变性(AMD)是一种复杂的疾病，是导致老年性黄斑变性 老年人中的失明。干性AMD病因不明，无治疗方法。富含脂肪的黄褐斑 存款是干性AMD的无声标志。视网膜色素上皮(RPE)可能是 AMD的原发病变部位。缺乏AMD小鼠模型是推进这一目标的障碍 研究领域。最近，我们发现RPE特异性CLIC4基因敲除(KO)小鼠发育完全 AMD样病理生理学的谱系，包括视功能受损、玻璃斑样病变 沉积，和严重的RPE细胞丢失。CLIC4是一种氧化还原敏感的多效性蛋白。我们的 研究表明，CLIC4缺乏改变了无数的信号通路，这些信号通路是 维持RPE动态平衡所必需的。特别是，CLIC4-KO RPE细胞具有丰富的脂质 监管失调。我们提出了两个具体的目标来理解CLIC4的S在耦合几个 脂类稳态的各个方面--新陈代谢、储存和运输。我们会调查一下血脂 细胞生物学背景下RPE的动态平衡。首要目标是学习如何 作为CLIC4缺失的综合结果呈现出AMD样的病理生理学。 我们将研究Clic4的S在磷脂(Aim1)和鞘磷脂(Aim2)动态平衡中的作用 RPE(Aim1)在脂类代谢、储存和转运方面的作用。我们将使用 跨学科方法和最先进的技术(例如，成像质谱学- LC/MS-MS脂质组学、转录组学、3D电子显微镜)来研究这些问题 在体内和体外。所获得的信息将极大地促进我们对 RPE和AMD病因学的基础科学。它们也有很大的潜力发现 治疗AMD的新药靶点。

SUMMARY Aged-related macular degeneration (AMD) is a complex disease and the leading cause of blindness among the elderly. Dry AMD has unclear etiology and no treatment. Lipid-rich drusen deposits are the silent hallmark of dry AMD. The retinal pigment epithelium (RPE) is likely to be the primary lesion site of AMD. Lacking an AMD mouse model is a roadblock to advance this research field. Recently we showed that RPE-specific CLIC4 knockout (KO) mice develop a full spectrum of AMD-like pathophysiology, including the impaired visual function, the drusen-like deposition, and severe RPE cell loss. CLIC4 is a redox-sensing pleiotropic protein. Our characterizations showed CLIC4 deficiency alters a myriad of signaling pathways that are required for maintaining RPE homeostasis. In particular, CLIC4-KO RPE cells had profound lipid dysregulation. We proposed two specific aims to understand CLIC4's role in coupling several aspects of the lipid homeostasis-metabolism, storage, and transport. We will investigate the lipid homeostasis of the RPE in the context of cell biology. The overarching goal is to learn how integrated outcomes as a consequence of loss-of-CLIC4 present the AMD-like pathophysiology. We will investigate CLIC4’s role in the phospholipid (Aim1) and sphingolipid (Aim2) homeostasis of RPE (Aim1) in the aspects of the lipid metabolism, storage, and transport. We will use interdisciplinary approaches and state-of-the-art techniques (e.g., Imaging Mass Spectrometry- LC/MS-MS lipidomics, transcriptomes, 3D electron microscopy) to studies these questions both in vivo and in vitro. The obtained information will significantly advance our comprehension of the basic science of the RPE and AMD etiology. They also have a strong potential for discovering new drug targets to treat AMD.