Sex as a response to oxidative stress: A twofold increase in cellular reactive oxygen species activates sex genes

Aurora M. Nedelcu, Oana Marcu, Richard E. Michod

Research output: Contribution to journalArticlepeer-review

72 Scopus citations


Organisms are constantly subjected to factors that can alter the cellular redox balance and result in the formation of a series of highly reactive molecules known as reactive oxygen species (ROS). As ROS can be damaging to biological structures, cells evolved a series of mechanisms (e.g. cell-cycle arrest, programmed cell death) to respond to high levels of ROS (i.e. oxidative stress). Recently, we presented evidence that in a facultatively sexual lineage - the multicellular green alga Volvox carteri - sex is an additional response to increased levels of stress, and probably ROS and DNA damage. Here we show that, in V. carteri, (i) sex is triggered by an approximately twofold increase in the level of cellular ROS (induced either by the natural sex-inducing stress, namely heat, or by blocking the mitochondrial electron transport chain with antimycin A), and (ii) ROS are responsible for the activation of sex genes. As most types of stress result in the overproduction of ROS, we believe that our findings will prove to extend to other facultatively sexual lineages, which could be indicative of the ancestral role of sex as an adaptive response to stress and ROS-induced DNA damage.

Original languageEnglish (US)
Pages (from-to)1591-1596
Number of pages6
JournalProceedings of the Royal Society B: Biological Sciences
Issue number1548
StatePublished - Aug 7 2004


  • Facultatively sexual species
  • Oxidative stress
  • Reactive oxygen species
  • Sexual induction
  • Volvox caneri

ASJC Scopus subject areas

  • Biochemistry, Genetics and Molecular Biology(all)
  • Immunology and Microbiology(all)
  • Environmental Science(all)
  • Agricultural and Biological Sciences(all)


Dive into the research topics of 'Sex as a response to oxidative stress: A twofold increase in cellular reactive oxygen species activates sex genes'. Together they form a unique fingerprint.

Cite this