On the origin of the seed habit

我们项目的最终目标是更好地理解在进化过程中产生种子的近似机制。在这项工作的过程中，我们希望澄清的分子机制，特别是在基因调控网络（GRN）的创新，参与胚珠和种子的起源。我们将追求我们的目标，通过研究生殖的分子发育遗传学在新兴的模式系统水蕨richardii。作为蕨类植物，C. richardii是念珠藻的一员，代表现存种子植物的最近的生活亲属。种子植物包括被子植物（开花植物）和裸子植物。我们将以两种独立的方式追求我们的目标，一种是“靶向候选基因方法”，另一种是“无偏见的转录组方法”。在候选基因方法中，我们将首先重建陆地植物MIKCC型MADS-box基因的改进的同源性。通过这种方式，我们将确定蕨类植物中与种子植物中控制胚珠和种子发育的基因最接近的基因。同时，我们将在C中建立基因组编辑。使用CRISPR-Cas9的richardii。利用这种方法，我们将敲除最近的花器官和种子身份基因的亲属，如确定使用的同源性重建，在C。理查德。敲除植物的突变表型将提供这些基因在蕨类植物中的功能及其在种子起源过程中的潜在作用的见解。在转录组学方法中，我们将首先提供C. richardii孢子体。我们将把这些数据与不同种子植物的数据进行比较，这些种子植物包括裸子植物如挪威云杉（Picea abies）和开花植物如拟南芥、番茄和水稻。为了更好地区分祖先从派生的字符状态，我们还将包括合适的转录组的brandiete模型地钱多形和立碗藓到我们的比较。我们和研究单位ICIPS的其他几个成员获得的数据将用于开发基因调控网络的模型，使我们能够识别在进化过程中种子起源过程中调控基因的关键变化。

The ultimate goal of our project is to better understand the proximate mechanisms that brought about seeds during evolution. During the course of this work we want to clarify the molecular mechanisms, especially innovations in gene regulatory networks (GRN), that were involved in the origin of ovules and seeds. We will pursue our goal by studying the molecular developmental genetics of reproduction in the emerging model system Ceratopteris richardii. As a fern, C. richardii is a member of the monilophytes, which represent the closest living relatives of extant seed plants. Seed plants are comprised of angiosperms (flowering plants) and gymnosperms. We will pursue our goal in two independent ways, a ‘targeted candidate gene approach’, and an ‘unbiased transcriptomic approach’. In the candidate gene approach we will first reconstruct improved phylogenies of MIKCC-type MADS-box genes of land plants. This way we will identify the genes in ferns which are the closest relatives to the genes that control ovule and seed development in seed plants. In parallel, we will establish genome editing in C. richardii employing CRISPR-Cas9. Using this method we will knockout the closest relatives of floral organ and seed identity genes, as identified using the phylogeny reconstructions, in C. richardii. The mutant phenotypes of the knockout plants will provide insights into the function of these genes in ferns and their potential role during the origin of the seed. In the transcriptomics approach we will first provide transcriptome data of several informative developmental stages of the C. richardii sporophyte. We will compare this data with those of diverse seed plants, including gymnosperms such as Norway spruce (Picea abies) and flowering plants such as Arabidopsis, tomato and rice. To better distinguish ancestral from derived character states, we will also include suitable transcriptomes of the bryophyte models Marchantia polymorpha and Physcomitrium patens into our comparisons. The data obtained by us and several other members of the research unit ICIPS will be used to develop models of gene regulatory networks that will enable us to identify critical changes in regulatory genes during the origin of the seed in evolution.