DNA demethylation in maize endosperm gene regulation

除了胚胎，种子还含有胚乳，胚乳与胎座相似，因为胚乳是一种单独的受精产物，为胚胎提供营养。胚乳不仅在遗传学上不同于其他植物器官，而且在表观遗传学上也不同。特别是，胚乳中具有相同DNA序列的基因产生不同的物理特征，这取决于它们是母系遗传还是父系遗传。这个项目的目标是了解胚乳中的DNA是如何被修饰的，从而导致基因以这种方式进行调控。胚乳是人类消耗热量的主要来源，因此了解胚乳中的基因是如何调控的对农业科学来说很重要。虽然该项目将专注于世界上最重要的粮食作物之一玉米(玉米)，但通过这项工作发现的胚乳基因调控的基本原理也将适用于其他植物。该项目还将包括面向小学生和教师的外联部分，以鼓励生物职业道路和教育科学方法。在植物中，DNA由DNA糖基酶去甲基化。胚乳与其他组织的不同之处在于数千个基因组座位上特定DNA糖基酶的活性，这主要是通过模式植物拟南芥的工作证明的。该项目将建立在此基础上，但由于玉米的实验优势和其胚乳的农业重要性，该项目将与玉米进行研究。我们的目标是在糖基酶突变体和野生型胚乳中使用RNA、染色质和甲基化测序方法来确定哪些基因组特征招募糖基酶以及它们的去甲基化如何影响染色质结构和转录。此外，这些实验产生的数据将被用于设计合成基因表达模块，用于测试结果预测和控制胚乳中的基因表达。该项目由分子和细胞生物科学部门的遗传机制计划和生物科学总监综合组织系统部门的植物基因组研究计划联合资助。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

In addition to embryos, seeds contain endosperm, which is similar to the placenta in that it is a separate product of fertilization that provides nutrition to the embryo. Endosperm is different from other plant organs not only in terms of genetics, but also epigenetics. In particular, genes with identical DNA sequences in endosperm produce different physical traits depending on whether they were inherited maternally or paternally. The goal of this project is to understand how DNA is modified in endosperm to cause genes to be regulated in this way. Endosperm is the major source of calories for human consumption, so understanding how genes are regulated in endosperm is important for agricultural science. While the project will focus on maize (corn), one of the most important food crops in the world, fundamental principles of endosperm gene regulation discovered through this work will also apply to other plants. The project will also include an outreach component to elementary school students and teachers to encourage biology career paths and to educate on scientific methods.In plants, DNA is demethylated by DNA glycosylases. Endosperm is distinguished from other tissues by activity of specific DNA glycosylases at thousands of genomic loci, as evidenced primarily by work in the model plant Arabidopsis thaliana. This project will build on this foundation, but with research on maize because of its experimental advantages and the agricultural importance of its endosperm. The goals are to use RNA, chromatin, and methylation sequencing methods in glycosylase mutant and wild-type endosperm to determine what genomic features recruit glycosylases and how their demethylation affects chromatin structure and transcription. In addition, the data generated from these experiments will be used to design synthetic gene expression modules for testing the resulting predictions and for controlling gene expression in endosperm.This project is jointly funded by the Genetic Mechanisms program in the Division of Molecular and Cellular Biosciences and the Plant Genome Research Program in the Division of Integrative Organismal Systems of the Biological Sciences Directorate.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.