Chromatin organization in Arabidopsis root epidermal development

拟南芥根表皮发育中的染色质组织

• 批准号: BB/D011892/1
• 负责人: Peter Shaw
• 金额: $ 39.31万
• 依托单位: John Innes Centre
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2006
• 资助国家: 英国
• 起止时间: 2006 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=BB%2FD011892%2F1
• 关键词: Chromatin; organization; Arabidopsis; root; epidermal

In general, all the different types of cells that comprise a complex organism like a plant or an animal have the same genes. An important, but little understood, question is how a single set of genes can be used in different ways to produce these different types of cells. One answer that is now emerging is that the genes are modified in semi-permanent ways - epigenetically - so that some can be switched on and others cannot. Thus different types of cells have the same genes, but different epigenetic states, and use different subsets of genes. Important questions are how these epigenetic states are set up and to what extent and under what circumstances they can be changed. An understanding of this will have far-reaching consequences for biology and medicine. In animals, it is relatively difficult to change epigenetic states, which is probably one reason why many animal cell types, such as most nerve cells, cannot be regenerated. On the other hand, plant cells are much more flexible in their development, which is why, for example, plants can often be regenerated from pieces of tissue (cuttings) or even single cells. We think one reason for this is likely to lie in the way plant genomes, as embodied in chromatin (the complex of the DNA with many different specific proteins), are modified epigenetically. We have begun a detailed study of one gene that is responsible for causing specific cells in the root of a plant to become root hair cells. We have been able to show by advanced microscopy that the region of the DNA containing this gene is in a different physical state in cells that will become root hair cells from cells that will not. Furthermore, we have shown by looking at naturally occurring aberrant cells that this difference in state is reversible and is potentially reset every time the cells divide. In this proposal we want to study the detailed biochemical basis of the physical difference in this gene. This should ultimately allow us to find out how and why the genes are in different states in different cells, and how this state is set and reset. We expect that this will help to explain how plant cells can change their developmental fates more easily than animal cells.

一般说来，组成植物或动物等复杂有机体的所有不同类型的细胞都有相同的基因。一个重要但鲜为人知的问题是，如何以不同的方式使用一组基因来产生这些不同类型的细胞。现在出现的一个答案是，这些基因以半永久性的方式进行了修改--从表观遗传角度--这样一些基因就可以启动，而另一些则不能。因此，不同类型的细胞具有相同的基因，但表观遗传状态不同，并使用不同的基因亚集。重要的问题是这些表观遗传状态是如何建立的，以及在什么程度和什么情况下可以改变它们。对这一点的理解将对生物学和医学产生深远的影响。在动物中，改变表观遗传状态相对困难，这可能是许多动物细胞类型，如大多数神经细胞无法再生的原因之一。另一方面，植物细胞的发育要灵活得多，这就是为什么，例如，植物通常可以从组织块(插条)甚至单个细胞再生。我们认为，其中一个原因可能在于植物基因组，如染色质(DNA与许多不同特定蛋白质的复合体)所体现的方式，是表观遗传修饰的。我们已经开始了对一种基因的详细研究，该基因负责使植物根中的特定细胞成为根毛细胞。我们已经能够通过先进的显微镜显示，含有该基因的DNA区域在细胞中处于不同的物理状态，将从不会成为根毛细胞的细胞变成根毛细胞。此外，我们通过观察自然发生的异常细胞表明，这种状态的差异是可逆的，并可能在每次细胞分裂时重新设置。在这项提议中，我们想要研究该基因物理差异的详细生化基础。这最终应该会让我们找出基因在不同细胞中处于不同状态的方式和原因，以及这种状态是如何设置和重新设置的。我们预计这将有助于解释植物细胞如何比动物细胞更容易改变它们的发育命运。

项目成果

Two-photon Photoactivation to Measure Histone Exchange Dynamics in Plant Root Cells.

双光子光活化测量植物根细胞中的组蛋白交换动态。

• DOI: 10.21769/bioprotoc.1628
• 发表时间: 2015
• 期刊: Bio-protocol
• 影响因子: 0.8
• 作者: Rosa S