Role of noncoding RNA decay in glucose homeostasis

项目总结/摘要 RNA生物合成和衰变的调节对于这些细胞中的细胞内稳态和失调至关重要。 这一过程导致各种人类发育和代谢紊乱。虽然转录 RNA表达的调控已经被广泛研究，RNA衰变的重要性才刚刚开始 被人欣赏具体来说，研究非编码RNA（ncRNA）表达的调控， 由于它们的大小、丰度、修饰和/或结构的限制， 复杂性我们最近已经鉴定了一种3 '至5'核糖核酸外切酶Dis 3l 2作为主要参与者， 在ncRNA衰变中。在该研究中，我对Dis 3l 2底物进行了全面鉴定，发现 大多数Dis 312靶是ncRNA。这导致我们鉴定DIS 3L 2介导的衰变 (DMD)作为质量控制途径，确保ncRNA的保真度。人类生殖系突变 DIS 3L 2基因与帕尔曼综合征有关，帕尔曼综合征是一种罕见但具有破坏性的疾病 与早期致死、低血糖、肾脏异常和胰腺增生相关。这些 表明Dis 312缺失患者中失调的ncRNA衰变破坏代谢稳态。 该研究项目的主要目的是揭示Dis 3l 2缺陷如何导致功能受损。 仍然未知。了解ncRNA衰变在代谢中的作用， 特别是在葡萄糖稳态，我计划联合收割机几个创新的方法来研究， 分子和生理功能的Dis 3L 2酶使用在体外和体内系统。我有 确定了信号识别颗粒（SRP）的7SL RNA组分，这是一个关键的参与者， 内质网（ER）介导的翻译，作为Dis 3l 2的主要底物。我发现，在 在缺乏Dis 312的情况下，异常的7SL RNA在细胞中积累并扰乱ER介导的蛋白 翻译.我们已经产生了帕尔曼综合征的Dis 312敲除（KO）小鼠模型， 表现出人类患者的主要症状，包括围产期死亡，肾过度生长， 取消血糖和胰岛素分泌的调节。此外，Dis 3l 2缺失导致 体外ER-翻译、ER-钙稳态和胰岛素分泌受损。这直接证明了 Dis 3l 2在响应于葡萄糖刺激的胰岛素分泌调节中的作用。我将使用Dis 3l 2 KO 小鼠模型，以进一步确定受损的ER介导的蛋白质翻译对细胞增殖的影响。 和生物生理学。我的假设是，Dis 3l 2缺失损害了稳态ER相关的 由于异常7SL RNA的积累而导致蛋白质翻译。这是一项创新，因为 Dis 312介导的ncRNA衰变参与葡萄糖稳态以前没有被发现， 报道成功地完成这一建议对理解《公约》的基础具有广泛的意义。 葡萄糖体内平衡，并对糖尿病治疗的发展具有显著影响。

Project Summary/Abstract Regulation of RNA biogenesis and decay is critical for cellular homeostasis and dysregulation in these processes leads to a variety of human developmental and metabolic disorders. While the transcriptional regulation of RNA expression has been widely studied, the importance of RNA decay is only beginning to be appreciated. Specifically, studying the regulation of noncoding RNA (ncRNA) expression and decay is hampered due to limitations caused by their size, abundance, modifications, and/or structural complexities. We have recently identified a 3’-to-5’ exoribonuclease enzyme, Dis3l2, as a major player in ncRNA decay. In that study, I performed a global identification of Dis3l2 substrates and found that the majority of Dis3l2 targets are ncRNAs. This led to our identification of DIS3L2-Mediated Decay (DMD) as a quality control pathway that ensures the fidelity of ncRNAs. Germline mutations in human DIS3L2 gene have been linked to the Perlman syndrome that is a rare but devastating disorder associated with early lethality, hypoglycemia, kidney abnormalities, and hyperplasia in pancreas. These suggest that dysregulated ncRNA decay in Dis3l2-depleted patients disrupts metabolic homeostasis. The main aim of this research project is to unravel how Dis3l2 deficiency leads to the impaired function of metabolic organs remains unknown. To understand the role of ncRNA decay in metabolism and specially in glucose homeostasis, I plan to combine several innovative approaches to investigate the molecular and physiological functions of Dis3l2 enzyme using in vitro and in vivo systems. I have identified the 7SL RNA component of the signal recognition particle (SRP), a critical player in endoplasmic reticulum (ER)-mediated translation, as a major substrate of Dis3l2. I discovered that in the absence of Dis3l2, aberrant 7SL RNAs accumulate in the cells and perturb ER-mediated protein translation. We have generated a Dis3l2 knockout (KO) mouse model of Perlman syndrome that manifests the main symptoms of human patients including perinatal lethality, kidney overgrowth, abrogated regulation of blood glucose and insulin secretion. Moreover, Dis3l2 depletion caused impaired ER-translation, ER-calcium homeostasis and insulin secretion in vitro. This proves a direct role of Dis3l2 in regulation of insulin secretion in response to glucose stimulation. I will utilize Dis3l2 KO mouse model to further determine the effect of impaired ER-mediated protein translation on cellular and organism physiology. My hypothesis is that Dis3l2 depletion impairs homeostatic ER-associated protein translation due to an accumulation of aberrant 7SL RNAs. This proposal is innovative because the involvement of the Dis3l2-mediated ncRNA decay in glucose homeostasis has not been previously reported. Successful completion of this proposal has broad implications in understanding the basis of glucose homeostasis and have a significant impact on the development of treatments for diabetes.