Collaborative Research: EDGE CMT: Genomic and molecular bases of pollination syndrome evolution in monkeyflowers

复杂性状的变异（例如，人的身高）通常是由多个基因引起的。这些多基因性状背后的致病基因和突变的鉴定和表征仍然是生物学中的核心挑战。植物中这种适应性最有趣的例子之一是授粉综合征，这是一套花的性状，使花和它们的动物授粉者之间的专门联系成为可能（例如，蜜蜂、蜂鸟、天蛾）。例如，蜂鸟授粉的花通常体积大，颜色红色，有丰富的花蜜生产和发达的生殖器官，而蜜蜂授粉的花通常显示各种颜色（但不是红色），花蜜量较少，插入的生殖器官和清晰的着陆平台。从一种授粉综合征到另一种授粉综合征的进化转变需要多个花性状的协调变化，每个性状由多个基因控制，然而这些转变在自然界中迅速发生在许多植物群体中。本研究采用了一种新的遗传模型系统，monkeyflowers，研究如何授粉综合征开关发生在基因组和分子水平。此外，本研究透过授粉症候群的透镜，将研究与学生教育及公众外展整合。具体活动包括在康涅狄格大学校园的一个公共花园组织传粉者观察实验，以提高公众对动物授粉服务的认识，在哈弗福德学院创建基于生物信息学课程的本科生研究体验，以及制作专业视频，将授粉综合征研究带到生活中，并在高订阅量的YouTube频道上发布，科学IRL（“在真实的生活中”）。该项目的总体目标是系统地剖析三种密切相关的猴花（Mimulus）物种之间花性状变异的基因组和分子基础，这三种猴花表现出三种不同的授粉综合征，包括蜜蜂授粉的M. lewisii、蜂鸟授粉的M. cardinalis和自花授粉的M.教区。这些物种适合通过稳定的转基因进行精细的遗传作图和严格的功能询问。我们计划通过实现以下具体目标来实现我们的总体目标：（i）产生高质量近等基因系（NIL），其与亲本物种的区别仅在于从另一物种渗入的单个花性状基因座，并使用NIL遗传剖析授粉综合征开关背后的每个数量性状基因座（QTL），（ii）使用稳定的转基因实验在功能上表征单个QTL下的致病基因和突变。（iii）使用加权基因共表达网络分析构建控制授粉综合征组分性状的基因调控网络/模块。这项研究的结果预计将提供一个深入的，全基因组范围内的授粉综合征开关的因果基因的观点，以确定一组基因调控模块控制个人花性状，应广泛适用于其他植物系统，并揭示新的分子机制，可以通知表型进化的研究不仅在植物，该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Variation in complex traits (e.g., human height) is usually caused by multiple genes. Identification and characterization of the causal genes and mutations underlying these multi-gene traits remain a central challenge in biology. One of the most intriguing examples of such adaptations in plants is the pollination syndrome, a suite of floral traits that enable specialized associations between flowers and their animal pollinators (e.g., bees, hummingbirds, hawkmoths). For example, hummingbird-pollinated flowers are usually large in size, red in color, with copious nectar production and exerted reproductive organs, whereas bee-pollinated flowers usually display various colors (but not red), a smaller quantity of nectar, inserted reproductive organs, and a clear landing platform. Evolutionary transitions from one pollination syndrome to another require coordinated changes of multiple floral traits, with each trait controlled by multiple genes, yet these switches occur rapidly in nature in many plant groups. This study employs a new genetic model system, monkeyflowers, to investigate how pollination syndrome switches occur at the genomic and molecular level. Furthermore, this study integrates research with student education and public outreach through the lens of pollination syndromes. Specific activities include organized pollinator observation experiments in a common garden on the University of Connecticut campus to raise public awareness of animal pollination service, creation of a bioinformatic Course-based Undergraduate Research Experience at Haverford College, and production of professional videos that bring pollination syndrome research to life to be released on a highly subscribed YouTube channel, Science IRL (‘in real life’).The overall objective of this project is to systematically dissect the genomic and molecular bases of floral trait variation among three closely related monkeyflower (Mimulus) species that display three distinct pollination syndromes, including the bee-pollinated M. lewisii, the hummingbird-pollinated M. cardinalis, and the self-pollinated M. parishii. These species are amenable to fine-scale genetic mapping and rigorous functional interrogation through stable transgenics. We plan to accomplish our overall objective by pursuing the following specific aims: (i) Generate high-quality near-isogenic lines (NILs), which differ from a parental species by only a single floral trait locus introgressed from another species, and use the NILs to genetically dissect each quantitative trait locus (QTL) underlying the pollination syndrome switches, (ii) Functionally characterize the causal genes and mutations under individual QTLs using stable transgenic experiments, (iii) Construct gene regulatory networks/modules that control pollination syndrome component traits using weighted gene co-expression network analysis. Results from this study are anticipated to provide an in-depth, genome-wide view of the causal genes underlying pollination syndrome switches, to identify a set of gene regulatory modules controlling individual floral traits that should be widely applicable in other plant systems, and to reveal novel molecular mechanisms that can inform studies of phenotypic evolution in not only plants, but also other organisms.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.