Evolutionary genetics of adaptation in natural populations of Arabidopsis thaliana

拟南芥自然种群适应的进化遗传学

• 批准号: 1743273
• 负责人: Christopher Oakley
• 金额: $ 64.61万
• 依托单位: Purdue University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-02-01 至 2020-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1743273&HistoricalAwards=false
• 关键词: Evolutionary; genetics; adaptation; natural; populations

Understanding how organisms adapt to the many challenges they experience in nature is a central goal in biology. Knowledge of the genetic mechanisms underlying adaptation in nature is also useful for increasing crop yields and for the conservation of wild species. One such challenge faced by organisms at high latitudes is freezing temperatures. This research investigates the genetics of freezing tolerance in the mouse-eared cress, a relative of many crop species that has become a "model" organism for which many genetic tools have been developed. In earlier work, the researchers collected seeds of this species from Italy and Sweden and planted them in experimental gardens located in each country. They found that freezing tolerance is required to survive the long, cold winters in Sweden, whereas freezing tolerance reduces performance in Italy. This result exemplifies the concept of biological "trade-offs"; adaptation to one environment often reduces performance elsewhere. This simple principle can explain why there are so many different species on earth, in that each species is adapted to a particular environment. The research investigates the genetic control of freezing tolerance and explores the mechanisms that contribute to the tradeoff in performance across environments. The genetic mechanisms identified in these studies may be useful tools for producing new crop varieties with increased yield in cold climates. In addition, the research team will perform outreach activities that advance scientific literacy and promote careers in science. Michigan State University scientists will contribute to a partnership between K-12 teachers and the W.K. Kellogg Biological Station to develop lesson plans that support Next Generation Science Standards (NGSS) for inquiry based learning.The research employs cutting edge genetic technologies to address the mechanisms and adaptive value of freezing tolerance using three complementary approaches. First, the genetic basis of freezing tolerance will be further examined in the two original populations in Sweden and Italy using new lines manipulating freezing tolerance genes in otherwise homogeneous parental backgrounds. These lines will then be grown in controlled environment chambers and in the field to estimate the importance of freezing tolerance genes for genetic trade-offs in performance across environments. Second, the genetic basis of freezing tolerance will be investigated in four new populations from Scandinavia and Spain with dramatic differences in freezing tolerance. Third, this research will be expanded to an even broader scale, asking if the same genes for freezing tolerance found in these focal populations are found in other geographic regions. The techniques employed in part three are similar to those used to study the genetics of many human diseases. Taken together, these studies examine the genetic basis of freezing tolerance in a broad diversity of natural populations and assess the mechanisms of performance trade-offs for this important adaptive trait.

了解生物体如何适应它们在自然界中经历的许多挑战是生物学的核心目标。了解自然界适应的遗传机制也有助于提高作物产量和保护野生物种。高纬度生物面临的一个挑战是冰冻温度。这项研究调查了耐冻性的遗传学在鼠耳水芹，一个相对的许多作物物种，已成为一个“模式”的生物体，许多遗传工具已被开发。在早期的工作中，研究人员从意大利和瑞典收集了该物种的种子，并将其种植在位于每个国家的实验花园中。他们发现，在瑞典，耐寒性是在漫长寒冷的冬季生存所必需的，而在意大利，耐寒性会降低性能。这一结果证实了生物“权衡”的概念;适应一种环境往往会降低其他地方的表现。这个简单的原理可以解释为什么地球上有这么多不同的物种，因为每个物种都适应特定的环境。该研究调查了抗冻性的遗传控制，并探索了有助于在不同环境中权衡性能的机制。这些研究中确定的遗传机制可能是在寒冷气候下生产新的作物品种以提高产量的有用工具。此外，研究小组将开展推广活动，促进科学素养和促进科学事业。密歇根州立大学的科学家们将为K-12教师和W.K.之间的伙伴关系做出贡献。凯洛格生物站制定课程计划，支持下一代科学标准（NGSS）的探究式学习。该研究采用先进的遗传技术，以解决机制和适应价值的抗冻性使用三个互补的方法。首先，在瑞典和意大利的两个原始种群中，将使用在其他同质亲本背景中操纵抗冻基因的新品系进一步研究抗冻性的遗传基础。然后，这些品系将在受控环境室和田间生长，以估计耐冻基因对跨环境性能的遗传权衡的重要性。其次，将在来自斯堪的纳维亚和西班牙的四个新种群中研究抗冻性的遗传基础，这些种群在抗冻性方面存在巨大差异。第三，这项研究将扩大到更广泛的范围，询问在这些重点人群中发现的耐冷冻基因是否在其他地理区域发现。第三部分中采用的技术与用于研究许多人类疾病遗传学的技术相似。两者合计，这些研究探讨了在广泛多样的自然种群的抗冻性的遗传基础，并评估这一重要的适应性性状的性能权衡的机制。