Effects of early life exposure to ultraviolet C radiation on mitochondrial DNA content, transcription, ATP production, and oxygen consumption in developing Caenorhabditis elegans.
Journal Article (Journal Article)
Background
Mitochondrial DNA (mtDNA) is present in multiple copies per cell and undergoes dramatic amplification during development. The impacts of mtDNA damage incurred early in development are not well understood, especially in the case of types of mtDNA damage that are irreparable, such as ultraviolet C radiation (UVC)-induced photodimers.Methods
We exposed first larval stage nematodes to UVC using a protocol that results in accumulated mtDNA damage but permits nuclear DNA (nDNA) repair. We then measured the transcriptional response, as well as oxygen consumption, ATP levels, and mtDNA copy number through adulthood.Results
Although the mtDNA damage persisted to the fourth larval stage, we observed only a relatively minor ~40% decrease in mtDNA copy number. Transcriptomic analysis suggested an inhibition of aerobic metabolism and developmental processes; mRNA levels for mtDNA-encoded genes were reduced ~50% at 3 hours post-treatment, but recovered and, in some cases, were upregulated at 24 and 48 hours post-exposure. The mtDNA polymerase γ was also induced ~8-fold at 48 hours post-exposure. Moreover, ATP levels and oxygen consumption were reduced in response to UVC exposure, with marked reductions of ~50% at the later larval stages.Conclusions
These results support the hypothesis that early life exposure to mitochondrial genotoxicants could result in mitochondrial dysfunction at later stages of life, thereby highlighting the potential health hazards of time-delayed effects of these genotoxicants in the environment.Full Text
Duke Authors
Cited Authors
- Leung, MCK; Rooney, JP; Ryde, IT; Bernal, AJ; Bess, AS; Crocker, TL; Ji, AQ; Meyer, JN
Published Date
- February 2013
Published In
Volume / Issue
- 14 /
Start / End Page
- 9 -
PubMed ID
- 23374645
Pubmed Central ID
- PMC3621653
Electronic International Standard Serial Number (EISSN)
- 2050-6511
International Standard Serial Number (ISSN)
- 2050-6511
Digital Object Identifier (DOI)
- 10.1186/2050-6511-14-9
Language
- eng