Collaborative Research: Analysis of rapidly evolving potassium channels in electric fish

合作研究：电鱼快速进化的钾通道分析

• 批准号: 1856243
• 负责人: Jason Gallant
• 金额: $ 68万
• 依托单位: Michigan State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-09-15 至 2024-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1856243&HistoricalAwards=false
• 关键词: Collaborative; Research; Analysis; rapidly; evolving

The purpose of this project is to understand how genetic changes contribute to the evolution of new animal signaling behaviors. The investigators of this collaborative project will study this question in weakly electric fishes from Africa, known as mormyrids. The team has previously discovered a protein, encoded by the gene kcna7a that has undergone intense natural selection mormyrids, which allows mormyrids to produce extremely short electric signals called an electric organ discharge (EOD). Despite the strong selection on mormyrids for brief EOD pulses, the evolution of pulse duration varies dramatically across the more than 200 species of mormyrids, and long duration EOD pulses have evolved at least three times from short-duration EOD pulse ancestors. The underlying hypothesis of this project is that the long-duration EODs are the result of selection acting on amino acid substitutions in the kcna7a gene. In this project, the investigators will test this hypothesis by examining the biophysical properties of kcna7a in species that secondarily evolved long duration EODs, and conduct field-based behavioral studies to determine the selective factors that lead to the evolution of long duration EODs. This project will enhance infrastructure for research by adding data products, refined functionality, and tools to the broadly utilized EFISH Genomics Web Portal, promote teaching and learning by ongoing mentorship of undergraduates, graduate students and postdoctoral associates associated and broaden participation by continuing the productive relationship with a network of institutional partners to recruit talented personnel from underrepresented groups, working with Huston-Tillotson University, a HBCU in Austin, TX.A major goal of 21st century biology is to understand how changes at the molecular level result in phenotypic changes at the organismal level. Despite the growing progress in unraveling the "molecular basis of phenotype" in a wide variety of taxa, it is important to maintain the view that forces at higher levels of biological organization shape phenotypes from the "top down". In many systems, these factors are well known, but their precise connection to identified genetic variants is still poorly understood. In electric fish, the selective forces that influence electric phenotype are known, the loci that produce them are identified, the specific nucleotides within these loci that affect function are characterized, and these loci are known to be targets of selection on macroevolutionary scales. In Specific Aim 1, this project will: determine the biophysical basis of secondary evolution of long EOD pulses by sequencing kcna7a in species that secondarily evolved long duration EODs and their congeners with short duration EODs, measuring their biophysical properties, examining the role of specific sites using site-directed mutagenesis, and determining whether secondarily derived long-duration EODs evolved once or multiple times in parallel. In Specific Aim 2, the investigators will determine whether species that produce long duration EODs have long-duration APs and, and whether properties of kcna7a currents are sufficient to lengthen them, using a combination of electrophysiology and computational modeling. In Specific Aim 3, the investigators will determine the selective factors that lead to the evolution of long duration EODs using by performing field studies in Gabon West-Central Africa. A investigators will continue their efforts to broaden participation of underrepresented groups in partnership with an HBCU.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.

该项目的目的是了解遗传变化如何促进新的动物信号行为的进化。这个合作项目的研究人员将在非洲的弱电鱼类（被称为mormyrids）中研究这个问题。该团队先前发现了一种由基因kcna7a编码的蛋白质，该蛋白质经历了强烈的自然选择，使mormyrids能够产生称为电器官放电（EOD）的极短电信号。尽管有很强的选择性，对mormyrids的短暂EOD脉冲，脉冲持续时间的演变显着不同的mormyrids的200多个物种，和长持续时间的EOD脉冲进化至少三次从短持续时间的EOD脉冲的祖先。该项目的基本假设是，长期EOD是选择作用于kcna7a基因中的氨基酸替换的结果。在这个项目中，研究人员将通过检查kcna 7a在次级进化长持续时间EOD的物种中的生物物理特性来测试这一假设，并进行基于场的行为研究，以确定导致长持续时间EOD进化的选择性因素。该项目将通过为广泛使用的EFISH基因组学门户网站增加数据产品、改进功能和工具来加强研究基础设施，通过对相关本科生、研究生和博士后的持续指导来促进教学，并通过继续与机构合作伙伴网络建立富有成效的关系来扩大参与，从代表性不足的群体中招募人才，21世纪世纪生物学的一个主要目标是了解分子水平的变化如何导致生物体水平的表型变化。尽管越来越多的进展，在解开“表型的分子基础”在各种各样的分类群，重要的是要保持这样的观点，即在更高水平的生物组织形状表型从“自上而下”的力量。在许多系统中，这些因素是众所周知的，但它们与已鉴定的遗传变异的精确联系仍然知之甚少。在电鱼中，影响电表型的选择力是已知的，产生它们的基因座被鉴定，这些基因座内影响功能的特定核苷酸被表征，并且这些基因座已知是宏观进化尺度上选择的目标。在具体目标1中，该项目将：确定爆炸物长脉冲二次进化的生物物理基础，方法是对二次进化出长持续时间爆炸物的物种及其具有短持续时间爆炸物的同源物中的kcna 7a进行测序，测量其生物物理特性，利用定点诱变研究特定位点的作用，并确定二次衍生的长持续时间爆炸物是一次进化还是多次平行进化。在具体目标2中，研究人员将确定产生长持续时间EOD的物种是否具有长持续时间AP，以及kcna 7a电流的特性是否足以延长它们，使用电生理学和计算建模的组合。在具体目标3中，研究人员将通过在非洲中西部加蓬进行实地研究，确定导致长期EOD演变的选择性因素。调查人员将继续努力扩大与HBCU合作的代表性不足的群体的参与。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。

项目成果

Timing and precision of rattlesnake spinal motoneurons are determined by the KV72/3 potassium channel

• DOI: 10.1016/j.cub.2023.11.062
• 发表时间: 2024-01-22
• 期刊: CURRENT BIOLOGY
• 影响因子: 9.2
• 作者: Bothe，Maximilian S.;Kohl，Tobias;Chagnaud，Boris P.
• 通讯作者: Chagnaud，Boris P.