Administrative Supplement to Recover Losses for the Project entitled "Examining C

过去十年的研究揭示了染色质修饰酶和染色质重塑酶在协调调节生物钟中的重要作用。这并不出人意料，因为真核生物生物钟的核心元素是转录负反馈环。染色质具有组织真核DNA的功能，但也为转录创造了障碍。这就需要染色质重塑在维持昼夜节律中的作用。在这项提议中，我试图进一步定义发生在脉孢子菌中心时钟基因频率上的修饰，并研究异染色质在时钟和时钟控制的基因表达中的作用。这里讨论的实验将使用一种组合的方法来检验这个问题。在具体目标1中，我建议分离处于天然染色质状态的中央时钟基因频率，并用质谱仪鉴定染色质的修饰。在特定的目标2中，我将研究KMT1 DIM-5是如何指向染色质的，以及H3K9甲基化在时钟和时钟控制的基因表达中的作用。在特定的目标3中，我检查基因组结构是否存在昼夜节律的时钟调节变化。在这些目标中获得的数据将被比较和对比，以了解基因组结构和时钟调控的基因表达之间的关系。总体而言，这一建议将进一步加深我们对染色质结构变化如何影响昼夜调控基因表达的理解。

Research over the past decade has revealed an important role for chromatin-modifying and chromatin-remodeling enzymes in coordinated regulation of the circadian clock. This is not unexpected given that a core element in eukaryotic circadian clocks is a transcriptional negative feedback loop. Chromatin functions to organize eukaryotic DNA, but also creates a barrier for transcription. This necessitates a role for chromatin remodeling in maintaining circadian rhythms. In this proposal, I am seeking to further define the modifications that occur at the Neurospora central clock gene frequency and examine the role of heterochromatin in clock and clock-controlled gene expression. Experiments discussed herein will examine this problem using a combined approach. In Specific Aim 1, I propose to isolate the central clock gene frequency in its native chromatin state and identify chromatin modification by Mass Spectrometry. In Specific Aim 2, I will examine how the KMT1 DIM-5 is directed to chromatin and the role of H3K9 methylation in clock and clock controlled gene expression. In Specific Aim 3, I examine if there are circadian clock-regulated changes to genome structure. Data obtained in these aims will be compared and contrasted to understand the relationship between genome structure and clock regulated gene expression. Overall, this proposal will further our understanding of how chromatin structural changes effects circadian regulated gene expression.