植物开裂性状起源和演化的分子机制--基于小立碗藓精子器开裂机制研究

开裂性状（例如果实开裂和花药开裂）是植物对陆地环境长期适应的结果，与植物种群繁衍及演化密切相关。植物开裂性状的起源和适应性进化机制研究是进化生物学的热点问题之一。近些年来的研究工作使我们对果实和花药开裂的分子机制有了初步的认识。然而，由于缺少苔藓植物相关研究，开裂性状起源和演化的分子机制目前仍不清楚。通过整合现有的结果，我们认为开裂器官中特殊排列的细胞壁加厚结构，是开裂性状的关键要素，同时也是开裂分子调控网络的核心，其起源可能在维管植物出现之前。为了验证我们的假说，本项目拟选取苔藓模式植物小立碗藓为研究材料，揭示精子器开裂的分子机制，并关注相关基因所构成的调控网络在不同植物类群中的变化，最终阐明开裂性状起源和演化的分子机制。本项目的开展有望在获得一批创新性研究成果的同时，在植物创新性状起源和适应性进化机制等理论问题研究中取得重要进展。

Dehiscence, such as fruit dehiscence and anther dehiscence, reflects the adaption of plants to the habitats that support plants to propagate and evolve. It has been widely focused to understand the genetic mechanisms underlying origin and evolution of dehiscence. Considerable progress has been made in understanding the mechanisms of fruit dehiscence and anther dehiscence respectively. However, relatively little is known about how they have had evolved, due to the absence of knowledge on dehiscence in bryophytes, the earliest land plant lineages. Recent studies suggested the arrangement of cell wall thickening in the tissues that line the margins of a dehiscence region is a key trait for the organs to split. We hypothesized the cell wall thickening program as a core niche from which the dehiscence-regulating network developed, and the origin of this genetic pathway may trace back to the common ancestors shared by bryophytes and vascular plant lineages. To verify our hypothesis, we will investigate the mechanism governing antheridium burst in Physcomitrella patens, with the aim to understand the evolution of dehiscence in land plants. This proposal aims to yield an array of novel findings, that could shed lights on the mechanisms leading to adaptive innovations and subsequent evolutions in land plants.