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

总结 视网膜相关性黄斑变性（AMD）是一种复杂的疾病，是导致视网膜病变的主要原因。 老年人的失明。干性AMD病因不明，无治疗方法。富脂性玻璃疣 沉积物是干性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鼠标模型是推进这一目标的一个障碍 研究领域。最近，我们发现RPE特异性CLIC 4基因敲除（KO）小鼠发育为一个完整的 AMD样病理生理学谱，包括视觉功能受损、玻璃疣样 沉积和严重的RPE细胞损失。CLIC 4是一种氧化还原敏感多效性蛋白。我们 表征显示CLIC 4缺陷改变了无数的信号通路， 维持RPE稳态所需的。特别地，CLIC 4-KO RPE细胞具有深刻的脂质代谢， 失调我们提出了两个具体的目标，以了解CLIC 4在耦合几个 脂质体内平衡的各个方面-代谢、储存和运输。我们将研究脂质 在细胞生物学的背景下，RPE的稳态。首要目标是学习如何 作为CLIC丧失的结果的综合结果4呈现AMD样病理生理学。 我们将研究CLIC 4在磷脂（Aim 1）和鞘脂（Aim 2）稳态中的作用 RPE（Aim 1）在脂质代谢、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- 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。所获得的信息将大大促进我们对 RPE和AMD病因学的基础科学。他们也有很强的潜力去发现 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.