DISSERTATION RESEARCH: A case study of evolution of epigenetic regulators post-gene duplication: Understanding EMBRYONIC FLOWER2-mediated gene regulation in a moss

基因复制是新的遗传物质的重要来源，进化可以对这些物质起作用。新颖功能可以部分地包括原始功能或者可以是完全新颖的。在苔藓中的胚胎花2（EMF 2）蛋白的情况下，新复制的基因可能靶向新的基因进行抑制，或者它们可能各自靶向原始靶标的子集。这项研究具有重要的科学意义，因为它将作为一个模型来了解基因复制事件后调控基因的功能如何变化。此外，EMF 2蛋白是蛋白质复合物的一部分，在控制陆地植物的生命周期中很重要。因此，了解EMF 2介导的基因调控的进化将提供陆生植物生命的发育进化的更好的理解。然而，EMF 2基因不仅在植物进化中很重要，而且在动物发育中也是必需的。EMF 2基因突变或EMF 2蛋白量错误的人通常会患上癌症。尽管人类和植物亲缘关系较远，但揭示EMF 2基因调控背后的保守机制将有助于我们对人类疾病的了解。其他影响包括对本科生的指导和培训，沿着向K-12学校和公众的推广。 基因复制很重要，因为它是新蛋白质功能产生的主要机制。本研究旨在了解基因复制在基因调控进化中的作用。EMF 2基因是重要的基因调节器，确保基因在发育过程中的适当时间关闭并保持关闭。EMF 2基因在许多植物谱系的进化过程中经历了复制。一组重复事件产生了三个副本的EMF 2基因立碗藓，一个模式的苔藓物种，强大的遗传和基因组资源。本研究的主要目的是：1）通过基因重复事件的系统发育分析，了解EMF 2基因在藓类植物中的进化情况：2）通过分析立碗藓属EMF 2基因的突变体，了解EMF 2基因的功能;和3）为了了解立碗藓基因重复如何通过确定每个基因的靶向来改变EMF 2基因调控机制，EMF 2拷贝，并确定这种EMF 2靶向是否导致基因激活或抑制。总的来说，这项研究将提供一个基因调控后基因复制的演变的理解。

Gene duplication is an important source of novel genetic material on which evolution can act. The novel functions may partially include the original function or may be entirely novel. In the case of the EMBRYONIC FLOWER2 (EMF2) proteins in mosses, the newly duplicated genes may target new genes for repression or they may each target a subset of the original targets. This study is of scientific importance because it will serve as a model to understand how the function of regulatory genes change after a gene duplication event. Moreover, the EMF2 proteins are part of a protein complex that is important in controlling the life cycles of land plants. Thus, understanding the evolution of EMF2-mediated gene regulation will provide a better understanding of the developmental evolution of terrestrial plant life. The EMF2 genes, however, are not only important in plant evolution- they are necessary in animal development. Humans with mutated EMF2 genes or with the wrong amount of EMF2 protein will often develop cancer. Although humans and plants are distantly related, uncovering the conserved mechanisms behind EMF2 gene regulation will contribute to our understanding of human disease. Additional impacts include mentoring and training of undergraduates, along with outreach to K-12 schools and the general public. Gene duplication is important because it is the primary mechanism through which novel protein functions arise. This study aims to understand the role gene duplication has played in the evolution of gene regulation. The EMF2 genes are important gene regulators, ensuring that genes are turned off and remain off at the appropriate time during development. The EMF2 genes have undergone duplications during the evolution of many plant lineages. One set of duplication events has produced three copies of the EMF2 genes in Physcomitrella, a model moss species for which powerful genetic and genomic resources are available. The goals of this project are: 1) To understand the evolution of the EMF2 genes in the moss lineage by phylogenetic analysis of gene duplication events; 2) To understand the function of each of the three Physcomitrella EMF2 genes by analyzing mutants in these genes; and 3) To understand how the Physcomitrella gene duplications have modified the EMF2 gene regulation mechanism by determining which genes are targeted by each EMF2 copy and by determining whether this EMF2 targeting results in gene activation or repression. Overall, this study will provide an understanding of the evolution of gene regulation post-gene duplication.