Fungus, frogs and MHC: the role of sexual selection in the evolution of disease resistance

性选择是一种强大的进化力量，可以促进或抑制对环境挑战的适应。当种群面临新的病原体时，SS可以通过影响抗性等位基因的传播来影响其持久性；具体来说，主要组织相容性复合体（MHC）编码识别病原体和激活获得性免疫系统的蛋白质。许多脊椎动物优先与携带有益MHC等位基因的伴侣交配，从而赋予后代更高的抵抗力。在这里，我建议研究SS在两栖动物对壶菌病（chytridiomycosis）的抗性进化动力学中的作用，壶菌病是一种新兴的传染病，在世界范围内导致种群下降和灭绝。我将使用毒蛙，这是一个物种丰富的群体，其中不同物种的SS强度不同，并且正在经历急剧的数量下降。我将测试配偶选择是否受到I) MHC和ii)伴侣双方感染状况的影响。随后，我将通过比较分析和实地调查来iii)评估SS强度与物种对壶菌易感性之间的关系，验证SS选择的物种抗性更强的预测。该项目不仅有助于我们了解SS在适应和疾病动力学中的作用，而且还首次对两栖动物基于mhc的配偶选择进行了实验分析。通过确定壶菌抗性物种差异的主要因素，研究结果将与两栖动物保护高度相关，这将有助于确定保护重点。在我的学术生涯中，我一直在研究壶菌；这个项目可以让我专注于宿主，这是研究较少的对象，迫切需要保护。该项目将在格罗宁根大学进行，由SS和毒蛙专家Maan博士监督；实地工作将在巴西进行。

Sexual selection (SS) is a strong evolutionary force that can promote or inhibit adaptation to environmental challenges. When populations face novel pathogens, SS can influence their persistence by impacting the spread of resistance alleles; specifically, the Major Histocompatibility Complex (MHC) that encodes proteins that recognize pathogens and activate the acquired immune system. Many vertebrates preferentially mate with partners carrying beneficial MHC alleles, conferring higher resistance to the offspring. Here, I propose to study the role of SS in the evolutionary dynamics of amphibian resistance to chytridiomycosis (chytrid), an emerging infectious disease that is causing population declines and extinctions worldwide. I will use poison frogs, a species-rich group in which the strength of SS differs between species, and that is experiencing dramatic population declines. I will test whether mate choice is influenced by i) MHC and ii) infection status ofboth partners. Subsequently, I will use comparative analysis and field surveys to iii) evaluate the association between the strength of SS and species’ susceptibility to chytrid, testing the prediction that species with SS selection are more resistant.This project will not only contribute to our general understanding of the role of SS in adaptation and disease dynamics, but also present the first experimental analysis of MHC-based mate choice in amphibians. Results will be highly relevant for amphibian conservation, by identifying a major factor underlying species differences in chytrid resistance, which will help to set conservation priorities. I have worked with chytrid throughout my academic career; this project allows me to focus on the host, which has been the target of fewer studies and is in dire need of conservation. The project will be conducted at the University of Groningen under the supervision of Dr. Maan, an expert on SS and poison frogs; field work will be carried out in Brazil.