Transkriptionsanalyse einzelner isolierter Zellen zur Identifizierung von Genen, die während wichtiger Schritte der Entwicklung des weiblichen Gametophyten der Modelpflanze Arabidopsis eine Rolle spielen

繁殖是所有物种生命周期中至关重要的一步。在植物中，通过种子进行生殖包括一系列明确的发育步骤和许多由大量基因控制的离散分化事件。雌性有性生殖过程中的关键事件有：(1)大孢子母细胞减数分裂产生功能大孢子；(2)大孢子母细胞减数分裂产生功能大孢子；(3)大孢子母细胞产生容纳两个配子（卵细胞和双核中心细胞）的雌性配子体（胚囊）；(3)雌雄配子融合的双受精。尽管一个多世纪以来，雌性配子体的结构和发育引起了科学家们的关注（例如Strasburger， 1879），但胚囊形成的遗传和分子基础在很大程度上是未知的。到目前为止，只有少数与有性生殖有关的基因被分离出来并进行了研究。该项目的目标是鉴定拟南芥大孢子发生和巨孢子发生在单细胞中表达的重要基因。为此，将对MMC和功能性大孢子的转录组进行分析。我们将进一步研究候选基因对植物繁殖的作用，例如通过分析T-DNA插入系或筛选相互作用伙伴。这一研究成果将对我们进一步了解胚囊发育和植物生殖的分子机制有重要意义。

Reproduction is a crucial step in the life cycle of all species. In plants, reproduction through seeds involves the progression of well-defined developmental steps and many discrete differentiation events controlled by a large number of genes. Key events during female sexual reproduction are: (i) megasporogenesis involving meiosis of a megaspore mother cell (MMC) to give rise to the functional megaspore, (ii) megagametogenesis being the formation of the female gametophyte (embryo sac) harboring the two gametes (the egg cell and the bi-nucleate central cell) from the functional megaspore, and (iii) double fertilization during which the female and male gametes fuse. Although structure and development of the female gametophyte has attracted the attention of scientists for more than a century (e.g. Strasburger, 1879), the genetic and molecular basis underlying embryo sac formation is largely unknown. So far, only a small number of genes involved in sexual reproduction have been isolated and investigated.The goal of the proposed project is to identify genes expressed in single cells important for megasporogenesis and megagametogenesis in Arabidopsis thaliana. To this aim the transcriptomes of MMC and functional megaspores will be analyzed. The role of candidate genes of putative importance for plant reproduction will further be investigated, e.g. by analysis of T-DNA insertion lines or screens for interaction partners. This project will significantly contribute to our understanding of the molecular mechanism controlling embryo sac development and plant reproduction.