CAREER: Ecology and Genetics of Male/Female-Ratio Polymorphism in Natural Populations of the Silene Latifolia Plant

9876397泰勒索--也就是所谓的“自私基因元素”，是一种以牺牲自身所在的生物体为代价，促进自身世代传播的基因。通常，还有其他基因抑制自私因素的影响。这种基因间的对抗性相互作用被称为“基因组内冲突”。基因组内冲突被认为具有根本性的重要性，可能影响生殖隔离的起源、性染色体、性别比偏差、重复DNA和性别决定机制等。最近，随着实验研究证实它们存在于各种各样的分类群中，这些现象的重要性越来越明显。然而，很少有研究考察基因组内冲突的动态或其在自然种群中的历史重要性。宽叶硅烯是一种雌雄异株植物，其性别比多态性与动物基因组内冲突的经典例子非常相似，但更适合在自然种群中进行研究。本研究从两个方面对宽叶银杉的性比多态进行了研究，这两个方面对理解基因组内冲突具有普遍意义。首先，将在田间建立的实验种群中测量控制性别比例的等位基因的遗传传播率。其次，系统发育分析将评估基因组内冲突在该系统中的历史重要性，以及控制性别比的遗传机制的多样性。拟议的实验将对我们理解自然界中的性别比变化以及基因组内冲突的生物学意义做出重要贡献。这种冲突产生和解决的频率对我们理解性别决定机制的起源和孟德尔式种族隔离本身的稳定性至关重要。该项目的教育部分侧重于扩大实验室研究在本科课程中的作用，以及向有科学职业抱负的中学生介绍大学实验室研究经验的外联计划。

9876397 TaylorSo-called 'selfish genetic elements' are genes that enhance their own transmission across generations at the expense of the organism in which they reside. Often, there are other genes that suppress the effects of the selfish element. This antagonistic interaction between genes is known as 'intragenomic conflict'. Intragenomic conflict is thought to be of fundamental importance, perhaps influencing the origin of reproductive isolation, sex chromosomes, sex-ratio bias, repetitive DNA, and sex-determination mechanisms, among others. The perceived importance of these phenomena has grown recently as experimental studies have established their existence in a wide variety of taxa. Nevertheless, very few studies have examined the dynamics of intragenomic conflict or its historical importance in natural populations.Silene latifolia is a dioecious plant with a sex-ratio polymorphism that closely resembles classic examples of intragenomic conflict in animals, but is more amenable to research in natural populations. This research focuses on two aspects of the sex-ratio polymorphism in Silene latifolia that are of general importance for understanding intragenomic conflict. First, the rates of genetic transmission of alleles that control the sex ratio will be measured in experimental populations set up in the field. Second, a phylogenetic analysis will evaluate the historical importance of intragenomic conflict in this system and the diversity of genetic mechanisms controlling the sex ratio. The proposed experiments will make important contributions to our understanding of sex-ratio variation in nature, and the biological significance of intragenomic conflict. How often such conflicts arise and are resolved in nature is critical to our understanding of the origins of sex-determining mechanisms and the stability of Mendelian segregation itself. The educational component of this project focuses on expanding the role of laboratory research in undergraduate course curricula, and outreach programs to introduce the experience of research in university labs to secondary school students with career ambitions in science.