Professor of Chemistry and VP for Research
University of Cincinnati
Host: John Hunt
Title: The Effects of Ionizing Radiation on tRNA Expression, Modification and Damage Profiles
Abstract: Following the 1986 Chernobyl disaster, the area surrounding the damaged nuclear reactor continues to be polluted with ionizing radiation, and it has been declared unlivable for another 20,000 years. In spite of these harsh, radioactive conditions, many microorganisms, including several species of fungi, have been discovered growing on the walls of the reactor and in the reactor cooling water pool. These organisms appear to be harnessing the gamma radiation present for their own benefit, and are therefore considered to be “radiotrophic.”
A number of the most abundant microorganisms present in high ionizing radiation sites are melanin-containing molds. The mechanisms by which these radiotrophic organisms safely capture and utilize ionizing radiation as a source of energy is still unclear. The search for this mechanism has uncovered many insights about changes in gene expression, cell wall and structure, and the potential role of melanin in fungal cells, but little is known about RNA expression, modification and damage profiles.
We have been using a variety of approaches to characterize how the tRNA pools of radiotrophic organisms are impacted by and respond to ionizing radiation. These findings are placed into context through corresponding studies on both bacterial organisms that also tolerate high levels of ionizing radiation as well as how melanin-containing human cell lines are impacted. This presentation will summarize our findings to date and discuss potential mechanisms by which cells can mitigate harmful effects of ionizing radiation.
Author(s) and affiliations:
MJ Paulines, Congliang Sun, Ruoxia Zhao, Whitney Houser, Melissa Kelly, Balu Addepalli and Patrick A. Limbach
Department of Chemistry, University of Cincinnati, Cincinnati OH