The Role of Alternative RNA Splicing on Endothelial Cell Barrier Dysfunction in Acute Respiratory Distress Syndrome

急性呼吸窘迫综合征（ARDS）是一种致命的危重病，死亡率超过20 尽管有许多临床试验。因此，有必要更好地了解 ARDS的发生机制。ARDS也是独特的，因为它是一种常见的途径，发生在 许多导致危重病的疾病过程（创伤或败血症、烧伤、胰腺炎引起的休克）。ARDS 其特征在于血管渗透性，导致水肿和免疫细胞在肺中积聚。的 血管通透性增加是由于内皮细胞功能障碍，是本项目的重点。多 工作集中在基因和蛋白质表达上，而对RNA剪接的变化知之甚少。RNA 剪接是一种基本的分子功能，在所有细胞中，剪接发生在RNA转录之后，但在蛋白质转录之前。 其中内含子被移除而外显子被连接在一起。超过90%的人类基因 多个外显子具有选择性剪接事件。由于转录基因的变异率如此之高， 产生的蛋白质，剪接必须在精确的控制下，特别是在危重病的时候。许多 蛋白质参与RNA剪接的控制，包括U1- 70 K。初步数据显示在肺部 基因表达没有差异，但U1- 70 K有多个选择性剪接位点。这是 类似于先前的工作，表明ARDS导致膜结合蛋白的选择性剪接， 以可溶形式存在。我们假设在ARDS中，选择性剪接改变了U1- 70 K的蛋白亚型， 内皮细胞同种型的这种变化反过来又导致微血管通透性， 在ARDS期间肺中水肿和免疫细胞的隔离。目的1将确定U1- 70 K，以及这些亚型是否与肺血管通透性相关。 盲肠结扎穿孔致小鼠ARDS模型。目标2将决定 在ARDS中观察到的U1- 70 K亚型和内皮细胞的生理条件（高酸，低氧） 屏障功能障碍目的3将评估临床前模型中存在的U1- 70 K可变剪接事件是否 存在于患有严重疾病的人的样本中。更好地理解ARDS中的可变RNA剪接 将允许操纵该机制以改善结果并改善对该问题的解决的预测。 毁灭性综合征

Acute respiratory distress syndrome (ARDS) is a fatal critical illness with mortality rates greater than twenty percent despite numerous clinical trials. It is therefore essential to develop better understanding of the basic mechanisms of development of ARDS. ARDS is also unique in that it is a common pathway that occurs after many disease processes that result in critical illness (shock from trauma or sepsis, burns, pancreatitis). ARDS is characterized by vascular permeability leading to edema and accumulation of immune cells in the lung. The increased vascular permeability is due to endothelial cell dysfunction and is the focus of this project. Much work has focused on gene and protein expression with little known about changes in RNA splicing. RNA splicing is a basic molecular function that occurs in all cells directly after RNA transcription, but before protein translation in which introns are removed and exons are joined together. Over 90% of human genes with multiple exons have alternative splicing events. With such a high rate of variation from the transcribed gene to the produced protein, splicing must be under exquisite control, particularly in times of critical illness. Numerous proteins are involved in the control of RNA splicing, including U1-70K. Preliminary data suggest that in the lung there is no difference in gene expression, but rather multiple sites of alternative splicing of U1-70K. This is similar to previous work showing that ARDS leads to alternative splicing of membrane bound proteins resulting in a soluble form. We hypothesize that in ARDS alternative splicing alters the protein isoforms of U1-70K in endothelial cells. This change in the isoforms, in turn, results in the microvascular permeability and sequestration of edema and immune cells in the lungs during ARDS. Aim 1 will determine the isoforms of U1- 70K in endothelial cells and whether these isoforms are correlated with lung vascular permeability using a mouse model of ARDS caused by cecal ligation and puncture. Aim 2 will determine the effects of the physiological conditions (high acid, low oxygen) seen in ARDS on the U1-70K isoforms and endothelial cell barrier dysfunction. Aim 3 will assess if U1-70K alternative splicing events present in the pre-clinical model are present in samples from humans with critical illness. Better understanding of alternative RNA splicing in ARDS will allow manipulation of this mechanism to improve outcomes and improve prediction of resolution of this devastating syndrome.