Cell Division Pattern in Plants: Division Plane, Cytoskeleton and Organelle Migration in Selaginella Stomatogenesis

细胞骨架在细胞分裂调控中的作用 平面，有丝分裂和形态发生将在 蕨类植物卷柏属（Selaginella）的气孔发生 这个简单的系统 利用了两个最戏剧性的例子， 植物中已知的明确的形态发生途径：气孔发生和 单质体细胞分裂 在气孔发生中， 细胞从表皮原始细胞分化， 导致形成一对专门的保卫细胞。 在 单质体分裂、核分裂和质体分裂密切相关， 通过精确的形态发生质体迁移和 质体中纺锤体的组织。 总体目标 这项研究的目的是利用确定的途径， 气孔发生与形态发生质体现象 迁移以回答植物中的基本重要问题 形态发生 形态发生质体迁移提供了 细胞周期中极性变化的准确标记。 这 迁移将与更好地了解昼夜节律和 光刺激卷柏属叶绿体迁移的研究 运动 叶绿体已经得到了很好的研究，并提供了一个更好的 了解植物中肌动蛋白驱动运动的例子。 提出 研究包括现场观察和直接和间接 利用光定位f-肌动蛋白和微管（视频 增强微分干涉衬度，荧光，共聚焦 激光扫描）和透射电子显微镜。 药物将 用于干扰细胞骨架蛋白以确定 控制分裂平面、细胞器迁移和分裂，以及 在细胞成形和细胞壁沉积中， 成熟的保卫细胞。 这些研究将增加我们对这一现象的理解。 质体极性在单质体细胞分裂，并将 有助于了解细胞骨架的作用 在多细胞植物组织的模式化发育中。

The role of the cytoskeleton in regulation of the division plane, mitosis and morphogenesis will be investigated in stomatogenesis in the fern ally, Selaginella. This simple system takes advantage of two of the most dramatic examples of precisely defined morphogenetic pathways known in plants: stomatogenesis and monoplastidic cell division. In stomatogenesis, the guard mother cell differentiates from epidermal initials to depart on a pathway leading to formation of a pair of specialized guard cells. In monoplastidic division, nuclear and plastid division are intimately coordinated by precise morphogenetic plastid migrations and by organization of the spindle at the plastids. The overall objective of this research is to use the determinated pathway of stomatogenesis and the phenomenon of morphogenetic plastid migration to answer questions of fundamental importance in plant morphogenesis. Morphogenetic plastid migration provides an accurate marker of changes in polarity during the cell cycle. This migration will be compared with the better known circadian and photostimulated chloroplast migration in Selaginella. Movement of chloroplasts has been well studied and provides one of the better understood examples of actin driven motility in plants. Proposed studies include live observations and direct and indirect localization of f-actin and microtubules using light (video enhanced differential interference contrast, fluorescence, confocal laser scanning) and transmission electron microscopy. Drugs will be used to perturb cytoskeletal proteins to determine function in control of division plane, organelle migration, and division, and in cell shaping and wall deposition that leads to the distinctive form of mature guard cells. Such studies will increase our understanding of the phenomenon of plastid polarity in monoplastidic cell division, and will contribute to the general knowledge of the role of the cytoskeleton in patterned development in a multicellular plant tissue.