Exploring the role of a novel autoimmune disease-associated lncRNA in Treg biology

项目总结/摘要 长链非编码RNA（lncRNA）是目前公认的多种生物过程的重要调控因子。 RNA测序已经检测到数万种非编码转录本，但只有一小部分 其中的功能已得到表征。lncRNA具有潜在的临床意义，因为它们是 越来越多地被认为是开发新治疗方法的靶点。我们建立 特异性鉴定可能是免疫功能调节因子的lncRNA的系统方法 系统，并可能参与炎症和自身免疫性疾病。此发现管道集成了 来自全基因组关联研究（GWAS）的信息，小鼠之间的进化保守， 人类和免疫细胞中的差异表达模式。使用这种方法，我们已经确定了一个 以前未知的人类lncRNA，我们命名为lnc 15。lnc 15存在于小鼠和人类中， 与克罗恩病和溃疡性结肠炎相关的单核苷酸多态性重叠， 两次严重的肠道自身免疫疾病重要的是，我们已经发现lnc 15以高水平存在， 在调节性T细胞（TcB）中，但在其他T细胞亚群中仅处于低水平。我们已经生成了lnc 15敲除 有趣的是，他们观察到这些动物在一种小鼠模型中表现出恶化的疾病进展。 肠道炎症此外，从lnc 15缺陷小鼠中分离的TcR在抑制Lnc 15的表达方面不太有效。 初始T细胞的增殖，而lnc 15的过表达增强了IL-10的表达，这是一个重要的 T细胞的效应细胞因子。基于这些观察，我们假设lnc 15是Treg的一种新的调节因子， 功能这里提出的实验将通过确定lnc 15如何影响Treg来探索这一假设。 转录组和鉴定其蛋白质和染色质相互作用伴侣。为了评估生理 lnc 15在体内的相关性，我们进一步提出利用肠炎症的Treg特异性模型， 确定lnc 15缺乏对T细胞发育、分化和稳态的影响。

PROJECT SUMMARY/ABSTRACT Long non-coding RNAs (lncRNAs) are now established as important regulators of diverse biological processes. Tens of thousands of non-coding transcripts have been detected by RNA sequencing, yet only a minute fraction of these have been functionally characterized. LncRNAs are of potential clinical significance, as they are increasingly considered as targets for the development of novel therapeutic approaches. We have established a systematic approach to specifically identify lncRNAs that are likely to be functional regulators of the immune system and that may be involved in inflammatory and autoimmune diseases. This discovery pipeline integrates information from genome-wide association studies (GWAS), evolutionary conservation between mice and humans, and differential expression patterns in immune cells. Using this approach, we have identified a previously unknown human lncRNA, which we have named lnc15. Lnc15 is present in mice and humans, and overlaps with a single-nucleotide polymorphism that has been linked to Crohn’s disease and ulcerative colitis, two severe intestinal auto-immune pathologies. Importantly, we have found that lnc15 is present at high levels in regulatory T cells (Tregs) but only at low levels in other T-cell subsets. We have generated lnc15 knockout mice and, intriguingly, have observed that these animals exhibit exacerbated disease progression in a model of intestinal inflammation. Additionally, Tregs isolated from lnc15-deficient mice are less effective at suppressing the proliferation of naive T cells, whereas overexpression of lnc15 enhances expression of IL-10, an important effector cytokine of Tregs. Based on these observations, we hypothesize that lnc15 is a novel regulator of Treg function. The experiments proposed here will explore this hypothesis by determining how lnc15 affects the Treg transcriptome and identifying its protein and chromatin interaction partners. To evaluate the physiological relevance of lnc15 in vivo, we further propose to utilize Treg-specific models of intestinal inflammation and determine the effect of lnc15 deficiency on T-cell development, differentiation and homeostasis.