DISSERTATION RESEARCH: Patterns of Thermal Adaptation

论文研究：热适应模式

• 批准号: 0710044
• 负责人: Christina Burch
• 金额: $ 1.09万
• 依托单位: University of North Carolina at Chapel Hill
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-06-15 至 2008-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0710044&HistoricalAwards=false
• 关键词: DISSERTATION; RESEARCH; Patterns; Thermal; Adaptation

This project aims to identify patterns of thermal adaptation. To accomplish this goal, the investigators will conduct evolution experiments using laboratory populations of the bacteriophage G4, a virus that infects the bacterium E. coli. The investigators will adapt virus populations to high and low temperatures, identify the mutations responsible for adaptation by sequencing whole genomes, and measure the performance of the evolved phages over a wide temperature range. The investigators will determine if the adaptive mutations tend to occur in the same or different genes and address two hypotheses concerning thermal adaptation. These hypotheses are: (1) Cold-adapted viruses will have lower maximal growth rates than hotter- adapted viruses; and (2) Adaptation to a new temperature will result in a loss of performance at different temperatures. Both of these predictions stem from the idea that there are constraints on biochemical reactions that limit or reduce an organism's performance at particular temperatures. The ability of natural populations to tolerate thermal variation is crucial to geographic distribution and ultimately to species survival. Over short time scales--daily, seasonally, or yearly--thermal variation has tended to be predictable. However, changing temperatures across the world mean that thermal variation may not be so predictable in the future. The study of thermal adaptation should lead to a greater understanding of the effects of global warming, and it may be possible to identify populations at risk of extinction.

该项目旨在确定热适应的模式。 为了实现这一目标，研究人员将使用噬菌体G4的实验室种群进行进化实验，噬菌体G4是一种感染细菌E的病毒。杆菌 研究人员将使病毒种群适应高温和低温，通过对整个基因组进行测序来确定负责适应的突变，并测量进化的病毒在宽温度范围内的性能。 研究人员将确定适应性突变是否倾向于发生在相同或不同的基因中，并解决有关热适应的两个假设。 这些假设是：（1）冷适应病毒将具有比热适应病毒更低的最大生长速率;和（2）对新温度的适应将导致在不同温度下的性能损失。 这两种预测都源于这样一种观点，即生物化学反应受到限制，限制或降低了生物体在特定温度下的表现。 自然种群耐受温度变化的能力对地理分布和物种生存至关重要。 在短时间尺度上--每天、季节性或每年--温度变化往往是可预测的。 然而，世界各地气温的变化意味着未来的热变化可能无法预测。 对热适应的研究应有助于更好地了解全球变暖的影响，并有可能确定面临灭绝危险的种群。