Genetic origin, developmental mechanism, and evolutionary process of a novel phenotype in Mimulus (monkeyflowers)

项目摘要 质量上独特的新结构或图案的出现(例如，龟壳、甲壳虫的角、蝴蝶 颜色图案、植物花朵)是生物进化中最引人入胜的方面之一。怎么会这样呢 新的、复杂的特征已经产生和进化仍然是最重要但也是最具挑战性的特征之一 进化生物学的问题。人们普遍认为，新的结构或模式是通过增选或 重新连接先前存在的发育程序，但我们对具体的基因变化知之甚少 触发这种共同选择或发育重新连接，基因变化如何转化为新的 表型，触发需要什么样的发育预设定或隐秘的预模式 基因(S饰)产生了小说的表型以及这些神秘的前置模式是如何产生的，以及小说是如何 表型在自然栖息地(即进化过程)中出现的频率增加。该项目旨在解决 通过研究一种新的、定性独特的、进化出的色素沉积模式，这些基本问题 最近，在野生的马鞭草(深红色猴花)种群中，一种服从于 遗传和发育操纵以及进化分析或/和生态审讯。 我们建议：(I)通过以下方法确定新的色素沉着模式背后的致病基因和突变(S 基因图谱和转基因实验；(2)表征发育前环境(隐秘的前环境 图案)通过识别多个上游来形成新的着色图案 通过对色素改变的化学诱导突变体的分析，激活剂和抑制物 模式；(Iii)阐明进化过程中新的表型在 自然栖息地通过种群基因组学分析和野外实验。我们预计这些研究 将首次提供遗传和发育机制的详细视图以及 推动自然界中一种新的表型出现的进化过程。圆满完成 该项目还有望通过将重点从相关研究转移到该领域来推动这一领域的发展 以及发生在遥远的过去的形态创新的故事，到严格的遗传， 对仍处于早期阶段的新表型的发育和进化分析 浮现。

Project Summary The emergence of qualitatively distinct new structures or patterns (e.g., turtle shells, beetle horns, butterfly color patterns, plant flowers) is one of the most fascinating aspects of organismal evolution. How such novel, complex traits have originated and evolved remains one of the most important yet challenging problems of evolutionary biology. It is widely assumed that novel structures or patterns arise by co-option or rewiring of pre-existing developmental programs, but we know very little about the specific genetic changes that trigger such co-option or developmental rewiring, how the genetic changes translate to novel phenotypes, what kind of developmental pre-settings or cryptic pre-patterns are required for the the trigger gene(s) to produce the novel phenotype and how these cryptic pre-patterns come about, and how the novel phenotypes rise in frequency in natural habitats (i.e., the evolutionary process). This project is to address these fundamental questions by studying a novel, qualitatively distinct, pigmentation pattern that evolved very recently in a wild population of Mimulus verbenaceus (crimson monkeyflower), a species amenable to genetic and developmental manipulations as well as evolutionary analyses or/and ecological interrogations. We propose to: (i) Identify the causal gene and mutation(s) underlying the novel pigmentation pattern by genetic mapping and transgenic experiments; (ii) Characterize the developmental pre-settings (cryptic pre- patterns) required for the formation of the novel pigmentation pattern by identifying multiple upstream activators and repressors, through analysis of chemically induced mutants with altered pigmentation patterns; (iii) Elucidate the evolutionary process through which the novel phenotype rose in frequency in the natural habitat by population genomics analyses and field experiments. We anticipate that these studies will, for the first time, provide a detailed view of the genetic and developmental mechanisms as well as the evolutionary process driving the emergence of a novel phenotype in nature. The successful completion of this project is also expected to help move the field forward by shifting the focus from correlational studies and just-so stories of morphological innovations that happened in the distant past, to rigorous genetic, developmental, and evolutionary analyses of novel phenotypes that are still in the initial stage of emergence.