Oxysterol-Binding protein like 7 in chronic kidney disease

项目摘要 参与细胞脂代谢1和内质网应激2的代谢途径紊乱已被显示 在慢性肾脏疾病(CKD)的发病机制中起重要作用。WE3-6等7证明了ATP- 结合盒转运体A1(ABCA1)缺乏导致足细胞损伤和疾病进展 代谢性和非代谢性肾小球疾病。虽然ABCA1缺陷不足以导致 体外或体内足细胞损伤和蛋白尿，尽管导致胆固醇外流和线粒体受损 功能障碍5、ABCA1的过度表达或ABCA1(ABCA1i)5的药理诱导足以 抢救蛋白尿小鼠肾小球损伤。近距离标记及免疫沉淀法检测转基因细胞 潜在的靶点导致鉴定氧固醇结合到氧固醇结合蛋白(OSBP)样7(OSBPL7)是 ABCA1i8的目标。OSBPL7是一组参与脂质运动的脂结合蛋白的成员 在膜之间8。OSBPs在启动自噬，胆固醇从内质转移中起作用 网状结构(ER)到高尔基体，胆固醇外流，并调节ABCA1的表达10。然而，如果OSBPL7是 在肾脏中表达，以及它是否参与调节ABCA1介导的胆固醇外流或在 内质网功能在足细胞中的保存还没有被探索。拟议的研究将 研究OSBPL7在足细胞中的功能。根据我的初步数据，我假设 OSBPL7缺乏导致ABCA1依赖的胆固醇流出和ABCA1- 独立的内质网应激，从而将OSBPL7与足细胞损伤和CKD进展联系起来。我建议 根据体外和体内实验的具体目的：(SA1)在体外，确定OSBPL7在 在足细胞中调节ABCA1依赖的功能。(SA2)体外，确定其作用机制 OSBPL7缺乏可独立于ABCA1参与内质网应激。(SA3)在体内，确定是否恢复肾脏 OSBPL7水平足以维持Col4A3耗竭斑马鱼的肾功能。我已经创建了一个 由我的导师和合作导师支持的全面职业发展计划，以确保我 在这项研究计划中取得进展和成功，并促进我向独立研究的过渡 职业生涯专注于与肾小球疾病相关的脂代谢。本计划包括(1)定期 与我的导师、共同导师和咨询委员会会面，提供研究和职业指导，(2) 研究和职业发展研讨会，学习新的研究方法，以及(3)职业活动 成长，包括指导、出版、演示和申请独立研究资金。我的 培训将在迈阿密大学米勒商学院无与伦比的学术环境中进行 医学，提供专门的职业发展计划和必要的研究支持 通过我的导师、合作导师和机构核心服务提供。这项研究和职业 发展提案是我向独立国家过渡的雄心和能力的产物 研究生涯。

Project Summary Derangement of metabolic pathways involved in cellular lipid metabolism1 and ER stress2 have been shown to contribute to the pathogenesis of chronic kidney disease (CKD). We3-6 and others7 demonstrated that ATP- binding cassette transporter A1 (ABCA1) deficiency contributes to podocyte injury and disease progression of glomerular diseases of metabolic and non-metabolic origin. While ABCA1 deficiency is insufficient to cause podocyte injury, in vitro or in vivo, and proteinuria despite causing impaired cholesterol efflux and mitochondrial dysfunction5, overexpression of ABCA1 or pharmacological induction of ABCA1 (ABCA1i)5 was sufficient to rescue glomerular injury in proteinuric mice. Proximity labeling followed by immunoprecipitation of transfected potential targets led to identifying oxysterol binding to oxysterol-binding protein (OSBP) like 7 (OSBPL7) as the target of ABCA1i8. OSBPL7 is a member of a group of lipid-binding proteins involved in the movement of lipids between membranes8. OSBPs play a role in initiating autophagy9, cholesterol transfer from the endoplasmic reticulum (ER) to the Golgi, cholesterol efflux, and regulating ABCA1 expression10. However, if OSBPL7 is expressed in the kidney and if it is involved in regulating ABCA1-mediated cholesterol efflux or in the preservation of ER function in the podocyte has not been explored. The proposed research will investigate the function of OSBPL7 in podocytes. Based on my preliminary data, I hypothesize that OSBPL7 deficiency causes ABCA1-dependent impairment of cholesterol efflux and ABCA1- independent ER stress, thus linking OSBPL7 to podocyte injury and CKD progression. I propose the following specific aims using in vitro and in vivo approaches: (SA1) In vitro, determine the role of OSBPL7 in modulating ABCA1-dependent functions in podocytes. (SA2) In vitro, determine the mechanism by which OSBPL7 deficiency contributes to ER stress independent of ABCA1. (SA3) In vivo, determine if restoring renal OSBPL7 levels is sufficient to preserve renal function in col4a3 depleted zebrafish. I have created a comprehensive career development plan supported by my mentor and co-mentor to ensure my progress and success in this research proposal and facilitate my transition to an independent research career focused on lipid metabolism in association with glomerular disease. This plan includes (1) regular meetings with my mentor, co-mentors, and advisory committee, to provide research and career guidance, (2) research and career development seminars, learning new research methodologies, and (3) activities for career growth, including mentoring, publication, presentation, and application for independent research funding. My training will be conducted in an unparalleled academic environment at the University of Miami, Miller School of Medicine, which provides dedicated career development programs and necessary research support and supplies through my mentor, co-mentors, and institutional core services. This research and career development proposal is a product of my ambition and capacity to transition to an independent research career.