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MRL researchers hypothesize origin of circadian rhythms


A study led by Drs Akhilesh Reddy and John O’Neill at the MRL indicates that regular daily oscillations in oxidation and reduction of peroxiredoxin enzymes might be the forerunner of better known circadian mechanisms. Until very recently, all circadian rhythms were thought to involve fluctuations in protein concentration. However, earlier work from Reddy and O’Neill turned this on its head, showing cyclical oxidation and reduction of peroxredoxin proteins in the absence of gene transcription and translation. The group’s most recent study identifies the same peroxiredoxin mechanism in many different organisms, including eukaryotes, bacteria and archaea. Conservation of this mechanism leads them to propose these enzymes conferred an evolutionary advantage during the ‘Great Oxidation Event’, which occurred ~2.5 billion years ago, and that they might enable more elaborate circadian mechanisms.

This study is published in the following article


Peroxiredoxins are conserved markers of circadian rhythms

Edgar et al., Nature (2012) doi:10.1038/nature11088


For more about this research see:


Discover Magazine

New Scientist

Nature news article