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，通过种子繁殖涉及明确定义的发育步骤和许多由大量基因控制的离散分化事件的进程。雌性有性生殖过程中的关键事件是：(I)大孢子母细胞(MMC)减数分裂形成功能性大孢子，(Ii)大配子体(胚囊)形成含有两个配子(卵细胞和双核中心细胞)的雌配子体(胚囊)，以及(Iii)双受精，在此期间雌、雄配子融合。虽然雌配子体的结构和发育已经引起科学家们一个多世纪的关注(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，只有少量涉及有性繁殖的基因被分离和研究。该项目的目标是鉴定在单细胞中表达的与拟南芥大孢子发生和大配子发生有关的重要基因。为此，将分析MMC和功能大孢子的转录本。将进一步研究可能对植物繁殖具有重要意义的候选基因的作用，例如通过分析T-DNA插入线或筛选相互作用伙伴。该项目将有助于我们理解控制胚囊发育和植物繁殖的分子机制。

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.