Authors: Dan Zhou 1; Jin Xue 1; Tsering Stobdan 1; Gabriel Haddad 1,2,3
Affiliations: 1) Department of Pediatrics, University of California San Diego; 2) Department of Neuroscience, University of California San Diego; 3) The Rady Children's Hospital
Keywords: r. stress; e. quantitative traits
Hypoxic and oxidative stress are common pathological elements in many diseases. In order to understand the mechanisms underlying mechanisms regulating tolerance or susceptibility to hypoxic or oxidative stress-induced injuries, we developed two Drosophila melanogaster populations that can live perpetually in severe, normally lethal, hypoxic or hyperoxic environments through experimental evolution. From these populations, we generated a Panel of Low Oxygen Tolerant (PLOT) and a Panel of High Oxygen Tolerant (PHOT) isofemale lines (total 79 PLOT and 65 PHOT lines) to identify and study specific genetic mechanisms that are responsible for the hypoxia, or hyperoxia, tolerant trait. These isofemale lines showed significantly enhanced hypoxia or hyperoxia tolerance as compared to their wildtype parental and the wildtype DGRP isofemale lines. For example, 95% of the PLOT lines showed hypoxia tolerance with eclosion rate >50% at 5% O2 level. In contrast, none of the parental lines and only 15% of the DGRP lines had similar eclosion rates under the same hypoxic condition. Furthermore, under the lethal condition with 4% O2, the PLOT lines exhibited a wide range of eclosion rate from 1% to 80% with a clear pattern of Gaussian-Distribution. These PLOT and PHOT flies may provide us a unique opportunity to study the molecular basis of stress-directed evolution, such as the role of genetic variations in the protein coding regions and functional DNA elements in hypoxia, or hyperoxia, adaptation. In addition, these PLOT and PHOT lines can also be used to study phenotypic plasticity as well as genetic-epigenetic interactions in hypoxic or oxidative environments.