miR-29 In Hypertension

描述(由申请人提供)：本项目的目标是调查microRNA miR-29在高血压和肾脏损伤发展中的作用，并了解涉及的机制。MicroRNAs是一种内源性的调节RNA，主要通过与靶mRNAs的3‘-非翻译区(UTR)结合来减少蛋白质的表达。大量研究表明，microRNAs是基因表达的强大调节者，在包括几种心血管和肾脏疾病在内的多种疾病过程中发挥着关键作用。然而，大多数microRNAs在全身性高血压和高血压组织损伤的发生发展中的功能仍不清楚。Dahl盐敏感(SS)大鼠是一种广泛使用的人类高血压和相关肾损伤的动物模型，尤其是在非裔美国人中。SS.13BN大鼠具有显著的降低高血压和肾脏损伤的作用，并已被用作研究SS大鼠发病机制的对照。我们已经报道，与SS.13BN大鼠相比，高盐饮食的SS大鼠肾脏中microRNA miR-29b的表达下调。MIR-29直接抑制至少16个与细胞外基质(ECM)相关的基因，有助于预防SS.13BN肾脏的间质纤维化。此外，我们在正在进行的人类研究中发现，miR-29b在高血压肾损伤患者的肾脏中调节失调。然而，目前尚不清楚肾脏miR-29的不足是否参与SS大鼠的高血压和肾损伤的发生，肾脏miR-29是否保护SS.13BN大鼠免受高血压的影响，miR-29对高血压的影响有何机制，以及在SS大鼠肾脏中miR-29的表达是如何调节的。我们假设miR-29的不足，特别是肾脏中的miR-29不足，有助于盐源性高血压和肾脏损伤的发展。在目标1中，我们将利用我们刚刚培育的组织特异性miR-29转基因大鼠和局部敲除miR-29的方法来研究miR-29在盐诱导的高血压和SS大鼠肾脏损伤中的作用。在目标2中，我们将使用几种方法来研究miR-29调控的潜在机制及其保护作用，包括我们刚刚开发的分子复杂拉出和深度测序方法。令人振奋的初步数据支持了拟议项目的可行性。

DESCRIPTION (provided by applicant): The goal of the current project is to investigate the role of microRNA miR-29 in the development of hypertension and renal injury and understand the mechanisms involved. MicroRNAs are endogenous, regulatory RNAs that primarily reduce protein expression by binding to the 3'-untranslated region (UTR) of target mRNAs. Numerous studies have demonstrated that microRNAs are powerful regulators of gene expression and play crucial roles in a wide range of disease processes including several cardiovascular and renal diseases. However, the functional role of most microRNAs in the development of systemic hypertension and hypertensive tissue injury remains unknown. The Dahl salt-sensitive (SS) rat is a widely used animal model of human hypertension and related renal injury especially in African Americans. The consomic SS.13BN rat exhibits significantly attenuated hypertension and renal injury and has been used as a control for studying disease mechanisms in the SS rat. We have reported that microRNA miR-29b is down-regulated in the kidneys of SS rats on a high-salt diet compared to SS.13BN rats. miR-29 directly suppresses at least 16 genes related to extracellular matrix (ECM) and helps to prevent interstitial fibrosis in SS.13BN kidneys. Moreover, we found in ongoing human studies that miR-29b was dysregulated in the kidneys of patients with hypertensive renal injury. However, it remains unknown whether the insufficiency of renal miR-29 contributes to the development of hypertension and renal injury in the SS rat, whether renal miR-29 protects SS.13BN rats from developing hypertension, what mechanisms mediate any effect of miR-29 on hypertension, and how the expression of miR-29 is regulated in the kidneys of SS rats. We hypothesize that miR-29 insufficiencies, specifically in the kidney, contribute to the development of salt-induced hypertension and renal injury. In Aim 1, we will examine the functional role of miR-29 in the development of salt-induced hypertension and renal injury in the SS rat using tissue-specific miR-29 transgenic rats that we just developed and local knockdown of miR-29. In Aim 2, we will examine mechanisms underlying the regulation of miR-29 and its protective effect using several approaches including a molecular complex pull-out and deep sequencing method that we just developed. Exciting preliminary data support the feasibility of the proposed project.