Nucleolin Regulation of miRome by Shear Stress

动脉树中动脉粥样硬化病变的局灶性分布可归因于血管暴露， 内皮细胞（EC）对血管分支点和弯曲处的动脉粥样硬化振荡剪切（OS）的影响， 与血管直部处的动脉粥样硬化保护脉动剪切（PS）形成对比。这两种类型的流 模式诱导不同的表达谱的miRNAs（miRs），差异调节靶基因的表达， 基因，导致不同的功能结果。核仁素（Nucleolin，NCL）是一种多功能蛋白， 在通过表观遗传、转录、转录后和翻译调节细胞功能中的作用 规定我们认为，NCL通过其相互作用调节miRome（miR转录和成熟 与DNA（通过g-四链体序列）和RNA（通过UCCCGA共有序列）。我们的初步结果 已经证明PS诱导NCL的磷酸化，这导致NCL与 miR 23 b/27 b的启动子/增强子区域以增加miR转录。另一方面，在OS下，非 磷酸化的NCL与miR 93/miR 484和Drosha结合以促进miR成熟。这些新发现 导致了这一更新建议的假设：NCL是由动脉粥样硬化保护和 在转录和成熟水平上调节miRome，从而发挥 在健康和疾病的血管内稳态中起重要作用。为了验证这一假设，我们提出了 以下四个具体目的：1）研究NCL的PS与OS调节的分子机制 在miR转录组中，2）确定NCL的PS-与OS-调节的分子机制， 3）整合NCL对miRome的多层调控和功能性的 4）验证NCL在调节中的作用 体内血管功能。在拟议的研究中，我们将使用体外内皮细胞生物学， 体内小鼠模型，计算机网络构建/数据挖掘，以及来自患有 心血管疾病的研究，以破译NCL的流动调节机制-微罗马的调节。的 这一发现将使人们对NCL在调节健康和疾病中的血管功能方面的作用有新的认识 通过miR法规。 !

The focal distribution of atherosclerotic lesions in the arterial tree is attributable to the exposure of the vascular endothelial cells (ECs) to the atheroprone oscillatory shear (OS) at vessel branch points and curvatures, in contrast to the atheroprotective pulsatile shear (PS) at straight parts of the vessel. These two types of flow patterns induce distinct expression profiles of miRNAs (miRs) that differentially regulate the expression of target geness, resulting in distinct functional outcomes. Nucleolin (NCL) is a multi-functional protein that plays critical roles in regulating cell functions through epigenetic, transcriptional, post-transcriptional, and translational regulations. We propose that NCL regulates miRome (miR transcription and maturation) through its interactions with DNA (via g-quadruplex sequences) and RNA (via UCCCGA consensus sequence). Our preliminary results have demonstrated that PS induces the phosphorylation of NCL that leads to an increased binding of NCL to the promoter/enhancer regions of miR23b/27b to increase miR transcription. On the other hand, under OS, the non- phosphorylated NCL binds to miR93/miR484 and Drosha to facilitate miR maturation. These novel findings have led to the hypothesis of this renewal proposal: NCL is differentially regulated by atheroprotective and atheroprone flow patterns to modulate the miRome at transcriptional and maturation levels, thus playing an important role in vascular homeostasis in health and disease. To test this hypothesis, we propose the following four Specific Aims: 1) to examine the molecular mechanisms underlying PS- vs. OS-regulation of NCL in miR transcriptome, 2) to determine the molecular mechanisms underlying PS- vs. OS-regulation of NCL- modulated miR maturation, 3) to integrate the multi-layer regulations of miRome by NCL and the functional consequences under PS and OS with the use of systems approaches, 4) to validate the role of NCL in regulating vascular function in vivo. In the proposed research, we will use a combination of in vitro endothelial cell biology, in vivo mouse models, in silico network construction/data mining, and clinical samples derived from patients with cardiovascular diseases to decipher the mechanisms of flow modulation of NCL-regulation of miRome. The findings will result in novel understanding of the role of NCL in regulating vascular functions in health and disease via miR regulations. !