The Genetic Basis of Adaptive Differentiation in Two Species of Mimulus

两种酸酢浆草适应性分化的遗传基础

• 批准号: 0075660
• 负责人: Harvey Bradshaw
• 金额: $ 40.8万
• 依托单位: University of Washington
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-09-01 至 2005-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0075660&HistoricalAwards=false
• 关键词: Genetic; Basis; Adaptive; Differentiation; Two

0075660BradshawThe genetic mechanism of plant adaptation to increasing elevation, from sea level to 10,000 feet in the Sierra Nevada mountains, will be studied using a combination of laboratory and field experiments. Mimulus cardinalis, a plant species adapted to long, hot summers at low elevation, has been crossed with Mimulus lewisii, a closely-related species adapted to the short, cool growing season found in high-elevation alpine meadows. More than 50 years of research has shown that the offspring of crosses between these two species differ in their ability to survive and grow at low, middle, and high elevations. This study will use DNA-based genetic maps of the Mimulus chromosomes to identify the number of genes controlling survival, growth, and reproduction at three historically important field stations (Stanford, Mather, and Timberline) in central California.The gene pools of many closely related species are kept separate by the geographic isolation resulting from adaptation to different environments. Adaptation is believed to be the principal means by which biological diversity is created and maintained. The pace of adaptive evolution depends upon the number of genes that govern adaptive traits such as tolerance of extreme temperatures or number of flowers produced during the growing season. With modern methods of molecular biology and genome mapping, it is possible for the first time to estimate the number of genes required for organisms to adapt to different natural environments.

0075660Bradshaw 将通过实验室和现场实验相结合的方式来研究植物适应海拔升高（从海平面到内华达山脉 10,000 英尺）的遗传机制。 Mimulus cardinis 是一种适应低海拔漫长炎热夏季的植物物种，已与 Mimulus lewisii 杂交，后者是一种适应高海拔高山草甸短暂凉爽生长季节的密切相关物种。 50多年的研究表明，这两个物种杂交的后代在低、中、高海拔地区的生存和生长能力存在差异。 这项研究将使用基于 DNA 的酸浆菌染色体遗传图谱来确定加州中部三个历史上重要的野外观测站（斯坦福、马瑟和廷伯莱恩）控制生存、生长和繁殖的基因数量。相关物种因适应不同环境而产生的地理隔离而保持分离。 适应被认为是创造和维持生物多样性的主要手段。 适应性进化的速度取决于控制适应性特征的基因数量，例如对极端温度的耐受性或在生长季节产生的花朵数量。 借助现代分子生物学和基因组作图方法，首次可以估计生物体适应不同自然环境所需的基因数量。