BIODEMOGRAPHIC DROSOPHILA EXPERIMENTS

摘要：描述：（改编自申请书）：本提案描述了果蝇实验室种群的遗传和人口统计学实验。本研究的主要目的有四：(1)利用多层次的应激实验来估计脆弱性的种群异质性；(2)通过收集代谢率、生殖行为、生育能力和运动活动的纵向数据来检验“生理平台”；(3)对重组自交系进行qtl定位，验证多效性假说；(4)通过在多个环境中重复qtl作图，检验基因型x环境相互作用的特定遗传模型。拟议中的实验解决了一些基本问题：为什么死亡率曲线在老年时减速？死亡率动态变化的生物学相关性是什么？延长寿命的基因是多效性的吗？不同的基因会导致不同环境下的寿命差异吗？本实验的显著特点是：(1)样本量大；(2)强调死亡率动态；(3)人口统计学方法与生物学方法相结合；(4)研究者将使用最近构建的KI系，这对于qtl定位和多效性测试来说是非常宝贵的资源；(5)以前没有在任何实验人群中直接测量过虚弱的异质性。

Abstract: DESCRIPTION: (adapted from the application): This proposal describes genetic and demographic experiments with laboratory populations of Drosophila. There are four specific aims: (1) To estimate population heterogeneity for frailty, using multi-level stress experiments; (2) To test for "physiological plateaus" by collecting longitudinal data on metabolic rate, reproductive behavior, fertility, and 1ocomotor activity; (3) To test the pleiotropy hypothesis by QTL-mapping in recombinant inbred (RI) lines; (4) To test a specific genetic model of genotype x enviroment interaction by repeating the QTL-mapping in multiple environments. The proposed experiments address basic questions: Why do mortality curves decelerate at advanced ages? What are the biological correlates of altered mortality dynamics? Are the genes that extend life span pleiotropic? Do different genes cause variation in life span in different environments? Notable features of the proposed experiments are: (1) large sample sizes are used; (2) there is an emphasis on mortality dynamics; (3) the approach integrates demographic and biological methods; (4) the investigators will use recently constructed KI lines, which are an unusually valuable resource for QTL-mapping and pleiotropy tests; (5) heterogeneity for frailty has not previously been directly measured in any experimental population.