Collaborative Research: Transitions and Transcriptomics: a Novel Approach to Understanding Shifts in Floral Developmental Pathways Preceding the Origin of the Pentapetalae

合作研究：转变和转录组学：理解五瓣花起源之前花发育途径转变的新方法

• 批准号: 1455601
• 负责人: Andre Chanderbali
• 金额: $ 32.76万
• 依托单位: University of Florida
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-07-15 至 2021-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1455601&HistoricalAwards=false
• 关键词: Collaborative; Research; Transitions; Transcriptomics; Novel

Flowering plants are the most abundant and diverse form of plant life on Earth. This dominance is largely due to the evolutionary success of one group, the Pentapetalae, characterized by whorled flower parts in multiples of five, which account for over 70% of described species. In contrast, flower parts are arranged in multiples of three (monocots, for example), two, or a variable number in less abundant groups of flowering plants. The shift to whorled pentamery of the Pentapetalae occurred about 100 million years ago, and appears to have been one of the most successful evolutionary innovations of not only flowering plants, but of green plants in general. This research will investigate the evolution of the underlying genetic changes that contributed to this ancient evolutionary event. It promises to discover the new and/or modified genetic pathways that produced the typical Pentapetalae flower, one of the major mysteries of plant evolution. Several undergraduates will be trained in phylogenetic and molecular biology methods and analyses, and high school teachers will participate in the research through a summer workshop. Data generated will be shared freely online and will provide tools for other researchers and the public to investigate other questions about flowering plant evolution. The researchers will sequence genes expressed during flower development in a phylogenetically representative sample of flowering plants and employ state-of-the-art transcriptome analysis techniques to achieve three major goals. Firstly, phylogenetic relationships among lineages subtending the Pentapetalae clade will be reconstructed. Robustly resolved phylogenetic relationships of the lineages preceding the shift to the pentamerous whorled flower are currently lacking but pivotal to interpreting the evolutionary sequence of genetic changes that underlie this key morphological innovation. Secondly, several comparative methods will be used to identify, date, and determine the evolutionary impact of whole-genome and/or gene duplication event(s) that predate the origin of the Pentapetalae. The occurrence of whole-genome duplication events prior to Pentapetalae is widely acknowledged but their precise positions are uncertain. Lastly, RNA-seq and in situ hybridization approaches will be used to infer spatial patterns of gene expression in non-Pentapetalae versus Pentapetalae flowers to identify gene expression changes that correlate with a shift to whorled pentamery in the latter. Together, this integration of approaches will provide exciting new insights into our understanding of flowering plant evolution

开花植物是地球上最丰富多样的植物生命形式。这种优势在很大程度上是由于一个群体的进化成功，五瓣花，其特征是五倍的轮生花部分，占所描述物种的70%以上。与此相反，花的部分排列成三个的倍数（例如单子叶植物），两个，或者在数量较少的开花植物群中可变的数量。 五瓣花科植物向轮生五瓣花的转变发生在大约1亿年前，这似乎是开花植物和一般绿色植物最成功的进化创新之一。这项研究将调查导致这一古老进化事件的潜在遗传变化的进化。它有望发现新的和/或修改的遗传途径，产生典型的五瓣花，植物进化的主要奥秘之一。几名本科生将接受系统发育和分子生物学方法和分析的培训，高中教师将通过夏季研讨会参与研究。 所产生的数据将在网上免费分享，并将为其他研究人员和公众提供工具，以调查有关开花植物进化的其他问题。研究人员将对开花植物的遗传学代表性样本中花发育过程中表达的基因进行测序，并采用最先进的转录组分析技术来实现三个主要目标。首先，系统发育关系的谱系对Pentapetalae分支将被重建。目前还缺乏在向五数轮花转变之前的谱系的可靠的系统发育关系，但对于解释这一关键形态创新背后的遗传变化的进化序列至关重要。其次，几种比较方法将被用来识别，日期，并确定全基因组和/或基因复制事件（S）的Pentapetalae的起源之前的进化影响。在Pentapetalae之前发生的全基因组重复事件被广泛承认，但它们的精确位置不确定。最后，RNA-seq和原位杂交方法将用于推断非Pentapetalae与Pentapetalae花中基因表达的空间模式，以鉴定与后者向轮生五花性转变相关的基因表达变化。总之，这种方法的整合将为我们理解开花植物进化提供令人兴奋的新见解