A Platform for Identifying GlycoRNA and Identifying Biases in RNA Pulldown Experiments

生命存在所必需的两种生物聚合物RNA和碳水化合物。RNA是生物学“中心法则”中的关键角色，由DNA转录并翻译成蛋白质。然而，RNA在生物学中扮演着更多的角色，例如作为信使分子或作为细胞过程的催化剂。碳水化合物（有时被称为“聚糖”）传统上被认为是一种能量来源，尽管它们在调节和蛋白质折叠中也发挥着许多其他重要作用。直到最近，人们才认为这两种关键的生物聚合物没有共享一个界面。新的研究挑战了这一观点，指出了用聚糖功能化的RNA聚合物。这种新的杂交生物聚合物（称为glycoRNA）的含义目前尚不清楚，但它可能在理解疾病状态的基本生物学或开发疫苗等技术方面发挥作用。在此，我们提出了一种研究glycoRNA的新方法，即利用小分子靶向RNA的策略。这种方法有很多优点——它可以比基于蛋白质的方法靶向更大的基因组部分，并且比基于dna的方法更具选择性。我们最近发现，在研究RNA修饰领域，以及在化学生物学一般领域的许多研究中，一种常用的技术可能会出现一些以前未知的偏差。一种称为DBCO的分子通常用于富集感兴趣的靶RNA，但我们发现DBCO可能优先结合一些大RNA转录物。我们担心这可能会影响世界各地研究人员的研究结果，我们打算仔细量化这种相互作用，并找到避免未来研究偏差的方法。我们还打算找出在glycoRNA中可以找到哪些不同类型的糖。糖具有多种不同的结构，从众所周知的葡萄糖到其他相关的结构，如半乳糖和甘露糖。我们认为其中一种糖可能在glycoRNA中含量特别高，我们计划确定情况是否如此。最后，一旦我们开发出一种识别不同形式glycoRNA的可靠方法，我们计划研究它们在不同环境中的普遍程度。这些环境可能是不同的细胞类型，甚至是健康细胞和不健康细胞。例如，如果发现glycoRNA水平在不健康的细胞中以不同的水平存在，它们可能被用作识别疾病的诊断工具。这种方法将促进化学、生物学和病理学交叉领域的基础研究和转化研究。

Two of the biopolymers that are essential for the existence of life RNA and carbohydrates. RNA, a key player in the "central dogma" of biology, is transcribed from DNA and translated into proteins. However, RNA plays many more roles in biology, for instance as a messenger molecule or as a catalyst for cellular processes. Carbohydrates (sometimes known as "glycans") are traditionally thought of as a source of energy - although they also play many other important roles in regulation and protein folding. Until recently, these two crucial biopolymers were not thought to have shared an interface. New work has challenged this view, pointing toward RNA polymers that are functionalised with glycans. The implications of this new hybrid biopolymer (termed "glycoRNA") are currently unknown, but it could potentially play roles in understanding the fundamental biology of diseased states or in the development of technologies such as vaccines. Here, we propose a new method for studying glycoRNA, by using a strategy of targeting RNA with small molecules. The approach holds numerous advantages - it allows targeting a much larger fraction of the genome than protein-based approaches and holds the promise for being much more selective than DNA-based approaches.We recently discovered that a commonly-used technique in the field of studying RNA modifications, and indeed in many studies in the general area of chemical biology, may present some previously unknown biases. A molecule called DBCO is often used to enrich target RNA of interest, but we have found that DBCO may preferentially bind to some large RNA transcripts. We are worried this may be affecting the results of researchers around the world and we intend to carefully quantify this interaction and find ways to avoid the bias of future studies. We also intend to find out which different types of sugars can be found in glycoRNA. Sugars take on a diverse array of structures, from the well-known glucose to other, but related, ones such as galactose and mannose. We believe one of these sugars may be present in particularly high levels in glycoRNA and we plan to determine whether this is the case.Finally, once we have developed a robust method for identifying the different forms of glycoRNA, we plan to study how prevalent they are in different kinds of environments. These environments could be things such as different cell-types, or even in healthy versus unhealthy cells. If glycoRNA levels are found, for instance, to be present at different levels in unhealthy cells, they could potentially be used a diagnostic tool to identify disease. This approach will facilitate both basic and translational research at the intersection of chemistry, biology and pathology.