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• 1. [Article] Endogenous ROS Levels in C. Elegans Under Exogenous Stress Support Revision of Oxidative Stress Theory of Life-History Tradeoffs

  Background: The oxidative stress theory of life-history tradeoffs states that oxidative stress caused by damaging free radicals directly underpins tradeoffs between reproduction and longevity by altering ...

  Citation × Citation Citation Abstract Copy Title: Endogenous ROS Levels in C. Elegans Under Exogenous Stress Support Revision of Oxidative Stress Theory of Life-History Tradeoffs Author: Smith, Samson W., Latta, Leigh C., IV, Denver, Dee R., Estes, Suzanne Year: 2014 Background: The oxidative stress theory of life-history tradeoffs states that oxidative stress caused by damaging free radicals directly underpins tradeoffs between reproduction and longevity by altering the allocation of energetic resources between these tasks. We test this theory by characterizing the effects of exogenous oxidative insult and its interaction with thermal stress and diet quality on a suite of life-history traits and correlations in Caenorhabditis elegans nematodes. We also quantify demographic aging rates and endogenous reactive oxygen species (ROS) levels in live animals. Results: Our findings indicate a tradeoff between investment in reproduction and antioxidant defense (somatic maintenance) consistent with theoretical predictions, but correlations between standard life-history traits yield little evidence that oxidative stress generates strict tradeoffs. Increasing oxidative insult, however, shows a strong tendency to uncouple positive phenotypic correlations and, in particular, to reduce the correlation between reproduction and lifespan. We also found that mild oxidative insult results in lower levels of endogenous ROS accompanied by hormetic changes in lifespan, demographic aging, and reproduction that disappear in combined-stress treatments–consistent with the oxidative stress theory of aging. Conclusions: Our findings demonstrate that oxidative stress is a direct contributor to life-history trait variation and that traditional tradeoffs are not necessary to invoke oxidative stress as a mediator of relationships between life-history traits, supporting previous calls for revisions to theory. Title: Endogenous ROS Levels in C. Elegans Under Exogenous Stress Support Revision of Oxidative Stress Theory of Life-History Tradeoffs Author: Smith, Samson W., Latta, Leigh C., IV, Denver, Dee R., Estes, Suzanne Year: 2014 Background: The oxidative stress theory of life-history tradeoffs states that oxidative stress caused by damaging free radicals directly underpins tradeoffs between reproduction and longevity by altering the allocation of energetic resources between these tasks. We test this theory by characterizing the effects of exogenous oxidative insult and its interaction with thermal stress and diet quality on a suite of life-history traits and correlations in Caenorhabditis elegans nematodes. We also quantify demographic aging rates and endogenous reactive oxygen species (ROS) levels in live animals. Results: Our findings indicate a tradeoff between investment in reproduction and antioxidant defense (somatic maintenance) consistent with theoretical predictions, but correlations between standard life-history traits yield little evidence that oxidative stress generates strict tradeoffs. Increasing oxidative insult, however, shows a strong tendency to uncouple positive phenotypic correlations and, in particular, to reduce the correlation between reproduction and lifespan. We also found that mild oxidative insult results in lower levels of endogenous ROS accompanied by hormetic changes in lifespan, demographic aging, and reproduction that disappear in combined-stress treatments–consistent with the oxidative stress theory of aging. Conclusions: Our findings demonstrate that oxidative stress is a direct contributor to life-history trait variation and that traditional tradeoffs are not necessary to invoke oxidative stress as a mediator of relationships between life-history traits, supporting previous calls for revisions to theory. Close

• 2. [Article] THE ROLE OF CHROMODOMAIN PROTEIN 1 (CDP-1) AT NEUROSPORA CRASSA HETEROCHROMATIN

  36 pages. A thesis presented to the Department of Biology and the Clark Honors College of the University of Oregon in partial fulfillment of the requirements for degree of Bachelor of Science, Spring 2...

  Citation × Citation Citation Abstract Copy Title: THE ROLE OF CHROMODOMAIN PROTEIN 1 (CDP-1) AT NEUROSPORA CRASSA HETEROCHROMATIN Author: Kim, Carissa Year: 2016 36 pages. A thesis presented to the Department of Biology and the Clark Honors College of the University of Oregon in partial fulfillment of the requirements for degree of Bachelor of Science, Spring 2016. Title: THE ROLE OF CHROMODOMAIN PROTEIN 1 (CDP-1) AT NEUROSPORA CRASSA HETEROCHROMATIN Author: Kim, Carissa Year: 2016 36 pages. A thesis presented to the Department of Biology and the Clark Honors College of the University of Oregon in partial fulfillment of the requirements for degree of Bachelor of Science, Spring 2016. Close