Excellence in Research: Developing a Model System for Studying the Determinants of Flower Morphology in Tropical Dioecious Trees

在许多植物中，人们可以在不同的植物上或在相同的植物上或在同时带有雄花(雄花)和雌花(雌花)的单花上发现雄花和雌花的存在。遗传和环境在决定这类植物的花类型和花器官发育方面的相互作用在很大程度上仍未得到研究。为了研究这一现象，项目组将使用原产于佛罗里达州南部、加勒比海、墨西哥南部和中美洲的新热带沿海地区的一种叫多叶球藻的植物。它是一种重要的原生热带乔木，上面提到的花卉图案有不同程度的表现。该团队将对这种植物物种的基因组进行排序，并描述在野生种群中发现的遗传学和开花模式，以确定基因组中对花和花器官的发育起到调节作用的区域。拟议的实验、数据收集和分析将提供一个极好的机会和素材，以培训代表基因组学、生物信息学、生物数据科学和保护方面各种人才的研究生和本科生。在雌雄异株类群中，决定哪些生物个体是雌雄异株的因素和机制还不是很清楚。在少数病例中，异形染色体被认为是一个主要的决定因素。在其他情况下，环境因素被确定为主要决定因素。然而，即使是这些案例似乎也没有确定严格的决定因素。此外，研究这些现象的生物系统绝大多数是草本的和温带的。该项目旨在研究遗传和环境在确定热带树木雌雄个体方面的相互作用，该热带树木具有不同的花表达。该项目将(1)使用短读和长读DNA测序以及邻近连接相结合的方法组装和注释研究分类群多叶球茎的完整核基因组，(2)通过种群采样、浅全基因组鸟枪测序和形态特异性阅读鉴定，确定有助于确定雌雄个体的遗传区域，以及(3)通过记录南佛罗里达多叶球茎种群的花形态比率与环境条件的关系，评估环境在确定花形态方面的贡献。该项目团队将为来自缺乏服务的社区的学生提供关于体验式学习、基因组学和生物信息学的培训和技能发展机会。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

In many plant species, one can find presence of male and female flowers on separate plants or on same plants or single flowers carrying both the stamens (male) and pistil (female) parts. The interplay between genetics and the environment in determining the flower type and development of floral organs in such plants remains largely uninvestigated. To study this phenomenon, the project team will use Coccoloba diversifolia (pigeonplum), a native of neotropical coastal areas of Southern Florida, Caribbean, Southern Mexico and Central America. It is an important native tropical tree and shows a varying degree of flower patterns mentioned above. The team will sequence the genome of this plant species and profile the genetics and flowering patterns found in a wild population to identify the regions of genome that play a role in regulating the development of flowers and floral organs. The proposed experiments, data collection and analyses will provide an excellent opportunity and source material to train the graduate and undergraduate students representing the full spectrum of diverse talent in genomics, bioinformatics, biological data science and conservation. Among dioecious taxa, the factors and mechanisms determining which biological individuals are pistillate and which are staminate are still not well understood. In a small minority of cases, heteromorphic chromosomes have been identified as one major determinant. In other cases, environmental factors have been identified as major determinants. Yet even these cases appear not to identify strict determinants. Moreover, the biological systems in which these phenomena are studied, have been overwhelmingly herbaceous and temperate. The project looks to examine the interplay of genetics and the environment in the determination of pistillate and staminate individuals in a tropical tree with variable floral expression. The project will (1) assemble and annotate the complete nuclear genome of the study taxon Coccoloba diversifolia using a combination of short- and long-read DNA sequencing along with proximity ligation, (2) identify the genetic regions contributing to the determination of pistillate or staminate individuals through population sampling, shallow whole genome shotgun sequencing and the identification of morphology-specific reads, and (3) assess the contribution of environment in determining flower morphology through the documentation of flower morphology ratios in relation to environmental conditions for populations of C. diversifolia in South Florida. The project team will provide training and skills development opportunities to students from underserved communities on experiential learning, genomics, and bioinformatics.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.