Collaborative Research: Nutritional physiology of life history allocation trade-offs

合作研究：生活史分配权衡的营养生理学

• 批准号: 1122075
• 负责人: Anthony Zera
• 金额: $ 32.4万
• 依托单位: University of Nebraska-Lincoln
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-09-01 至 2016-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1122075&HistoricalAwards=false
• 关键词: Collaborative; Research; Nutritional; physiology; life

Life history traits such as longevity, dispersal and total reproductive output are key organismal adaptations. Many life history traits are negatively coupled with each other because nutrients allocated towards one trait (e.g. egg production) are not available for another trait (e.g. production of lipid fuel for dispersal). The magnitude of trade-offs can be strongly influenced by the amount and quality of nutrients available to an organism, but currently little is known about how nutrient inputs affect life history trade-offs. Here this issue is investigated using a wing-polymorphic cricket, Gryllus firmus. This cricket exists as one of two genetically-specified forms, one adapted for flight (dispersal) at the expense of egg production, the other adapted to maximize reproduction at the expense of dispersal (it lacks flight muscle). Using a range of well-defined diets that differ in their protein-carbohydrate composition (and total caloric content), a comparison will be made that reveals how these two contrasting phenotypes differentially extract, interconvert, and eliminate protein and carbohydrate demanded by their specific life history. Specifically, this study will measure consumption and assimilation of protein and carbohydrates into body tissues, document how these two nutrients are allocated to flight and reproduction organs, and use radiotracer and enzymological studies of biochemical pathways to study interconversion and metabolic elimination of these two nutrients. An important focus will be identifying the physiological mechanisms that allow a particular phenotype to acquire/produce the biomolecules it needs (for its life history) in a constantly shifting nutritional environment. Results will be applicable to a wide range of organisms, including life history traits (e.g. longevity) in humans. This project also has a significant instructional component, including the training of a postdoctoral associate, research opportunities for undergraduate students, and the development of workshops for secondary school educators which provides novel approaches to teaching basic principles of evolution.

生活史特征，如寿命，扩散和总的生殖输出是关键的生物适应。许多生活史性状相互之间是负相关的，因为分配给一种性状(例如产蛋)的营养物质不能用于另一种性状(例如生产用于分散的脂类燃料)。营养取舍的大小会受到生物体可获得的营养素的数量和质量的强烈影响，但目前对营养输入如何影响生活史的取舍知之甚少。在这里，这个问题是使用翅膀多形的蟋蟀进行研究的。这种蟋蟀以两种基因特定的形式之一存在，一种适合飞行(扩散)，以牺牲产卵为代价，另一种适应于以牺牲扩散为代价最大限度地繁殖(它缺乏飞行肌肉)。使用一系列蛋白质-碳水化合物组成(和总卡路里含量)不同的明确定义的饮食，将进行比较，揭示这两种不同的表型如何不同地提取、相互转化和消除特定生活史所需的蛋白质和碳水化合物。具体地说，这项研究将测量蛋白质和碳水化合物在人体组织中的消耗和同化，记录这两种营养物质是如何分配到飞行和生殖器官的，并使用放射性示踪剂和生化途径的酶研究来研究这两种营养物质的相互转化和代谢消除。一个重要的焦点将是确定允许特定表型在不断变化的营养环境中获得/产生其所需的(其生活史)生物分子的生理机制。结果将适用于广泛的生物体，包括人类的生活史特征(例如长寿)。该项目还具有重要的教学内容，包括培训一名博士后助理，为本科生提供研究机会，并为中学教育工作者开发讲习班，为讲授进化论基本原理提供新的方法。