Determinants of higher order genome architecture

我的研究项目将研究DNA的三维结构--基因组是如何“打包”的--如何决定细胞的身份。这一研究问题将加深我们对组成我们体内不同组织和器官的细胞如何具有不同功能的理解(它们可以是皮肤细胞、肌肉细胞或神经元等)，尽管它们都拥有相同的基因组。我们的工作将建立在我们最近的发现基础上，即一类称为组蛋白变体的蛋白质在具有不同功能的细胞中以不同的方式包装DNA。在NSERC的资助下，我的研究小组将识别导致人类大脑中干细胞及其后代(神经元、星形胶质细胞和少突胶质细胞)DNA包装差异的组蛋白变体。我们的研究将破译将特定DNA结构与细胞功能联系起来的密码。这项研究对自然科学的影响是深远的。首先，我们将开发DNA包装的新概念，编程特定的细胞功能。因此，我们将产生新的知识和工具，这些知识和工具将很容易适应使用其他发育系统或疾病模型的科学家，因此我们的工作也有可能在其他领域进行发现。其次，近年来，再生医学非常重视将一种特定细胞转化为另一种细胞类型的倡议，例如将患有神经系统疾病的患者的皮肤细胞分化为健康的神经元，可以重新移植到同一患者体内。这种努力一直受到特定细胞DNA结构建立的分化障碍的阻碍，这阻止了转化为其他类型的细胞。通过显著提高我们对基因组结构和细胞功能之间关系的理解，我们的工作将打开新的机会，帮助再生医学努力获得可用于临床的适当分化的细胞。第三，改变染色质结构正变得越来越容易，因为针对染色质重塑酶的化合物越来越多，其中一些已经被批准用于人体。我们的研究所产生的知识将为有针对性的方法提供信息，这些方法结合特定的染色质重塑化合物来设计3D基因组结构中所需的变化并获得特定的细胞类型。第四，我们的研究将产生区分细胞类型的DNA结构“指纹”。鉴于我们对DNA结构和细胞功能之间密切相关的新认识，我们的研究计划将为人类细胞的功能特性提供前所未有的视角。

My research program will investigate how the three-dimensional architecture of the DNA - how the genome is "packaged" - determines the identity of a cell. This research question will deepen our understanding of how cells that make up different tissues and organs in our bodies have different functions (they can be skin cells, or muscle cells, or neurons, etc) although they all share the same genome. Our work will build on our recent findings that a class of proteins called histone variants have a role in packaging the DNA in different ways in cells that have different functions. With NSERC funding, my research group will identify the histone variants that are responsible for differences in DNA packaging between stem cells and their progeny (neurons, astrocytes and oligodendrocytes) in the human brain. Our studies will decipher the code that links a specific DNA architecture with cellular function. The implications of this research for the natural sciences are far reaching. First, we will develop the new concept of DNA packaging programming specific cell functions. We will therefore generate new knowledge and tools that will be readily adapted to scientists working with other developmental systems or with disease models, thereby our work has the potential to seed discoveries in other fields as well. Second, there has been significant emphasis in recent years on regenerative medicine initiatives to convert a given cell into another cell type, for instance differentiating skin cells from a patient affected by a neurological disease into healthy neurons that can be retransplanted into the same patient. Such efforts have been hampered by differentiation barriers erected by the DNA structure of a given cell, which prevents conversion into other cell types. By significantly improving our understanding of the relationship between genome architecture and cell function, our work will open new opportunities to aid regenerative medicine efforts to obtain properly differentiated cells that can be used for clinical purposes. Third, altering chromatin architecture is becoming increasingly easy because of the growing arsenal of compounds that target chromatin remodelling enzymes, some of which have already been approved for use in human subjects. The knowledge generated by our studies will inform targeted approaches that combine specific chromatin remodelling compounds to engineer the desired changes in 3D genome architecture and obtain specific cell types. Fourth, our studies will generate DNA architecture "fingerprints" that will distinguish between cell types. Given our emerging understanding of the tight correlation between DNA architecture and cell function, our research program will offer an unprecedented view of the functional properties of human cells.