BIODEMOGRAPHIC DROSOPHILA EXPERIMENTS

描述：(改编自应用程序)：本提案描述了对果蝇实验室种群进行的遗传和人口学实验。本研究有四个具体目标：(1)利用多水平胁迫实验估计群体脆弱性的异质性；(2)通过收集关于代谢率、生殖行为、育性和运动活动的纵向数据来检验“生理高原”；(3)通过在重组自交系中进行QTL定位来检验多效性假说；(4)通过在多个环境中重复QTL定位来检验特定的遗传模型。拟议中的实验解决了基本问题：为什么死亡率曲线在高龄时减速？死亡率动态变化的生物学关联是什么？延长寿命的基因是多效性的吗？在不同的环境中，不同的基因是否会导致寿命的差异？拟议实验的显著特点是：(1)使用大样本量；(2)强调死亡动力学；(3)该方法整合了人口学和生物学方法；(4)研究人员将使用最近构建的KI系，这是一个非常有价值的QTL定位和多效性测试资源；(5)脆弱性的异质性以前从未在任何实验群体中直接测量过。

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.