Investigating the regulation of distinct human adipocyte subpopulations

项目摘要 脂肪组织是能量平衡和葡萄糖稳态的核心参与者，它能够在面对压力时扩张。 为了安全地储存能量，它会产生热量过载，但它会变得过载和功能失调，导致 胰岛素抵抗和2型糖尿病形式的全身代谢损害。为了研究差异 在瘦和肥胖个体的单个细胞类型中，我进行了单核RNA测序（sNuc- seq）在人皮下和内脏白色脂肪组织上进行，并创建了存在于 白色脂肪组织。这项工作的一个主要发现是确定了不同的亚群， 脂肪细胞，其中一些与体重指数（BMI）有关。把我们的数据和基因组联系起来- 广泛的关联研究（GWAS）的代谢性状，如T2 D，我们还预测，一些脂肪细胞， 亚群与代谢疾病有关。该项目的目标是确定 使一个亚群比另一个亚群更易受影响，无论是在外部还是在转录上。为了做到这一点， sNuc-seq在减肥手术期间和之后从受试者收集的脂肪组织上进行，以表征 在减肥过程中脂肪细胞亚群的变化。接下来我将研究脂肪细胞的染色质状态 通过对来自脂肪细胞的单个核进行转座酶可降解染色质的测定， 瘦的和肥胖的个体的组织。最后，我将直接测试潜在的信号和转录调节因子 通过筛选潜在的信号调节因子以及CRISPRa筛选， 潜在的转录调节因子，试图重演不同的亚群在体外。我的经历 在单细胞分辨率下表征脂肪组织方面，以及我的导师和合作者的经验， 导师在研究脂肪细胞的转录和遗传调控，使我独特的定位，以回答 这些问题。总之，这些研究将提高我们对人类白色脂肪细胞多样性的认识 并将为我自己的独立实验室和整个社区的下游研究奠定基础。

Project Summary Adipose tissue is a central player in energy balance and glucose homeostasis, it is able to expand in the face of caloric overload in order to store energy safely, but it can become overloaded and dysfunctional, leading to systemic metabolic compromise in the form of insulin resistance and Type 2 diabetes. To investigate differences in individual cell types in lean and obese individuals, I have performed single nucleus RNA sequencing (sNuc- seq) on human subcutaneous and visceral white adipose tissue and created an atlas of cell types present in white adipose tissue. A major finding from this work was the identification of distinct subpopulations of adipocytes, some of which are associated with body mass index (BMI). By associating our data with genome- wide association studies (GWAS) for metabolic traits such as T2D, we additionally predict that some adipocyte subpopulations are associated with metabolic disease. The objective of this project is to identify factors that predispose one subpopulation over another, both externally as well as transcriptionally. To do this I will perform sNuc-seq on adipose tissue collected from subjects during and post-bariatric surgery in order to characterize the change in adipocyte subpopulation during weight loss. I will next interrogate the chromatin state of adipocyte subpoulations by performing the Assay for Transposase Accessible Chromatin on single nuclei from adipose tissue of lean and obese individuals. Finally, I will directly test potential signaling and transcriptional regulators of subpopulation identity by performing a screen of potential signaling regulators as well as a CRISPRa screen of potential transcriptional regulators to try to recapitulate distinct subpopulations in vitro. The experience that I have in characterizing adipose tissue at single cell resolution, as well as the experience of my mentor and co- mentor in studying transcriptional and genetic regulation of adipocytes make me uniquely positioned to answer these questions. Taken together, these studies will enhance our knowledge of human white adipocyte diversity and will set the stage for downstream studies in my own independent lab and in the community at large.