Collaborative Research: The Aquilegia Petal as a Model for the Elaboration and Evolution of Organ Shape

合作研究：耧斗菜花瓣作为器官形状的精细化和进化的模型

• 批准号: 1456217
• 负责人: Elena Kramer
• 金额: $ 41.93万
• 依托单位: Harvard University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-08-01 至 2019-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1456217&HistoricalAwards=false
• 关键词: Collaborative; Research; Aquilegia; Petal; Model

The body of a plant is made of just a few repeatedly produced structures, such as leaves and stems. However, these structures can vary tremendously in their shape both within an individual and between different species in predictable, consistent ways. This variation in shape is controlled by a combination of cell division and cell shape, which in turn must be controlled by variation in gene expression. The proposed research seeks to determine how complex shapes arise through development and the genes that control these processes. Thus this research will address the fundamental question of how organisms achieve the shapes of their bodies, which is critical to their survival. This research will also have broader impacts through the training of young scientists including undergraduates, graduate students and postdoctoral fellows with outreach efforts to recruit female and underrepresented minorities. The nectar spur of Aquilegia is a complex three-dimensional structure that is recently derived and highly variable among species and, thus, can serve as a powerful model for investigating the control and evolution of complex organ shape. Nectar spurs develop via an early phase of localized, oriented cell divisions that create the prepatterned spur cup, which is then followed by a period of highly anisotopic cell elongation that gives rise to the final length and shape of the spur. Among the closely related and interfertile species of Aquilegia, variation in spur length and shape is generated by changing several developmental parameters: length is primarily controlled by cell anisotropy, which is in turn controlled by the duration of cell elongation; curvature is generated by varying cell elongation between the distal vs. proximal compartments of the spur; and circumference is controlled both by changes in cell anisotropy and cell number in the radial orientation. Thus, understanding the development and evolution of Aquilegia spurs will provide insight into all of these fundamental aspects of lateral organ development, which can provide new perspectives on the evolution of lateral organs more broadly across the angiosperms. The proposed research seeks to integrate multiple lines of study drawn from the fields of developmental genetics, evolutionary genomics/genetics, and biophysics. Specifically, the project will elucidate the fundamental genetic control of petal spur development, explore the roles of hormonal signaling and biomechanical strain in controlling spur development, use QTL-based approaches to identify the genes involved in the diversification of spur shape and use comparative genomic approaches to identify selective sweeps associated with the origin of nectar spurs.

植物的身体仅由一些重复产生的结构组成，例如叶子和茎。然而，这些结构的形状在个体内部和不同物种之间可能以可预测的、一致的方式存在巨大差异。这种形状的变化是由细胞分裂和细胞形状的组合控制的，而细胞分裂和细胞形状又必须由基因表达的变化来控制。拟议的研究旨在确定复杂的形状是如何通过发育产生的以及控制这些过程的基因。因此，这项研究将解决生物体如何形成其身体形状的基本问题，这对其生存至关重要。这项研究还将通过培训年轻科学家（包括本科生、研究生和博士后研究员）以及招募女性和代表性不足的少数族裔的外展活动来产生更广泛的影响。 耧斗菜的花蜜刺是一种复杂的三维结构，是最近衍生出来的，并且在物种之间差异很大，因此可以作为研究复杂器官形状的控制和进化的强大模型。花蜜刺通过早期阶段的局部定向细胞分裂形成预图案化的刺杯，然后是一段高度各向异性的细胞伸长期，形成刺的最终长度和形状。在耧斗菜属密切相关且互育的物种中，刺长度和形状的变化是通过改变几个发育参数而产生的：长度主要由细胞各向异性控制，而细胞各向异性又由细胞伸长的持续时间控制；曲率是通过改变骨刺的远端和近端室之间的细胞伸长而产生的；周长由细胞各向异性和径向细胞数量的变化控制。因此，了解耧斗菜刺的发育和进化将有助于深入了解侧向器官发育的所有这些基本方面，这可以为更广泛地跨被子植物侧向器官的进化提供新的视角。拟议的研究旨在整合来自发育遗传学、进化基因组学/遗传学和生物物理学领域的多个研究领域。具体来说，该项目将阐明花瓣刺发育的基本遗传控制，探索激素信号和生物力学应变在控制刺发育中的作用，使用基于QTL的方法来识别参与刺形状多样化的基因，并使用比较基因组方法识别与花蜜刺起源相关的选择性清除。