Metabolic control of global gene expression during the Maternal-to-Zygotic Transition

摘要 卵子受精后，数千个基因在胚胎中被激活，而母体的mrna则被激活。 退化；这个过程被称为母体到受精卵的转变(MZT)。这项提议的目标是 破译合子基因的激活是如何与母体的mRNA衰退同步的。两者都是组蛋白 修饰和mRNA修饰N6-甲基腺苷(M6A)在MZT中起着突出的作用， 分别通过调控合子基因的转录和母体基因的清除。然而，这些信号 在这个关键的发育阶段控制染色质和mRNA修饰的变化在很大程度上 未知。这一提议将检验细胞新陈代谢变化协调全球的新假设 通过调节染色质所需代谢物的可用性，在MZT期间的基因表达 和信使核糖核酸的修饰。使用高分辨率质谱仪，在果蝇(D)。黑猩猩 在胚胎移植期间，我们确定了α-酮戊二酸(α-KG)水平的变化，这是一种必需的 组蛋白和RNA去甲基化酶的辅助因子。在这里，我们通过以下方式测试我们的中心假设 以下特定目标：(1)测试α-KG水平、组蛋白甲基化和全球转录之间的联系 合子基因的激活，以及(2)检测α-KG水平、m6A基因修饰和 母体的信使核糖核酸腐烂。D.黑腹鼠胚胎是研究黑腹鼠胚胎之间相互作用的理想系统。 新陈代谢和基因调控，因为有许多操作和测量的实验工具 体内代谢、染色质状态、信使核糖核酸修饰和转录。这项建议将适用于 分子、遗传和基因组方法，以展示代谢输入，如α-KG，如何塑造 通过控制两个染色质来控制发育转录组和协调关键发育过程 和信使核糖核酸的修饰。这项研究的发现将与理解不仅是发展 以及代谢功能障碍与基因表达异常相关的疾病，如 癌症和糖尿病。建立黑腹水母作为代谢研究的实验平台 作为这项研究计划的一部分，全球基因表达的调节和相关技能的获得将是 朝着实现我成为独立调查员的目标迈出了关键的下一步。

ABSTRACT After an egg is fertilized, many thousands of genes are turned on in the embryo while maternal mRNA is degraded; this process is called the maternal-to-zygotic transition (MZT). The goal of this proposal is to decipher how activation of zygotic genes is synchronized with maternal mRNA decay. Both histone modifications and the mRNA modification N6-methyladenosine (m6A) play prominent roles, during the MZT, by regulating transcription of zygotic genes and maternal mRNA clearance, respectively. However, the signals that control changes in chromatin and mRNA modifications in this critical developmental stage are largely unknown. This proposal will test the novel hypothesis that changes in cellular metabolism coordinate global gene expression during the MZT, through modulating the availability of metabolites required for chromatin and mRNA modifications. Using high-resolution mass-spectrometry, in Drosophila (D). melanogaster embryos during the MZT, we identified changes in the levels of alpha-ketoglutarate (α-KG), which is a required co-factor for histone and RNA demethylation enzymes. Here, we test our central hypothesis through the following specific aims: (1) test the link between α-KG levels, histone methylation, and global transcription activation of zygotic genes, and (2) test the link between α-KG levels, m6A modification of mRNA, and maternal mRNA decay. D. melanogaster embryos are an ideal system for studying the interplay between metabolism and gene regulation because there are many experimental tools for manipulating and measuring metabolism, chromatin state, mRNA modifications and transcription in vivo. This proposal will apply molecular, genetic and genomic approaches to demonstrate how metabolic inputs, such as α-KG, shape the developmental transcriptome and coordinate critical developmental processes by controlling both chromatin and mRNA modifications. Findings from this study will be relevant for understanding not only developmental processes but also diseases in which metabolic dysfunction is associated with abnormal gene expression, such as cancer and diabetes. Establishing D. melanogaster as an experimental platform for studying metabolic regulation of global gene expression and acquiring the relevant set of skills as part of this research plan will be a critical next step towards fulfilling my goal of becoming an independent investigator.