Dataset Information

Rising levels of atmospheric oxygen and evolution of Nrf2.

ABSTRACT: In mammals, the master transcription regulator of antioxidant defences is provided by the Nrf2 protein. Phylogenetic analyses of Nrf2 sequences are used here to derive a molecular clock that manifests persuasive evidence that Nrf2 orthologues emerged, and then diverged, at two time points that correlate with well-established geochemical and palaeobiological chronologies during progression of the 'Great Oxygenation Event'. We demonstrate that orthologues of Nrf2 first appeared in fungi around 1.5?Ga during the Paleoproterozoic when photosynthetic oxygen was being absorbed into the oceans. A subsequent significant divergence in Nrf2 is seen during the split between fungi and the Metazoa approximately 1.0-1.2?Ga, at a time when oceanic ventilation released free oxygen to the atmosphere, but with most being absorbed by methane oxidation and oxidative weathering of land surfaces until approximately 800?Ma. Atmospheric oxygen levels thereafter accumulated giving rise to metazoan success known as the Cambrian explosion commencing at ~541?Ma. Atmospheric O2 levels then rose in the mid Paleozoic (359-252?Ma), and Nrf2 diverged once again at the division between mammals and non-mammalian vertebrates during the Permian-Triassic boundary (~252?Ma). Understanding Nrf2 evolution as an effective antioxidant response may have repercussions for improved human health.

SUBMITTER: Gacesa R

PROVIDER: S-EPMC4906274 | biostudies-literature | 2016 Jun

REPOSITORIES: biostudies-literature

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Rising levels of atmospheric oxygen and evolution of Nrf2.

Gacesa Ranko R Dunlap Walter C WC Barlow David J DJ Laskowski Roman A RA Long Paul F PF

Scientific reports 20160614

In mammals, the master transcription regulator of antioxidant defences is provided by the Nrf2 protein. Phylogenetic analyses of Nrf2 sequences are used here to derive a molecular clock that manifests persuasive evidence that Nrf2 orthologues emerged, and then diverged, at two time points that correlate with well-established geochemical and palaeobiological chronologies during progression of the 'Great Oxygenation Event'. We demonstrate that orthologues of Nrf2 first appeared in fungi around 1.5 ...[more]

PMID: 27297177

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Dataset Information

Rising levels of atmospheric oxygen and evolution of Nrf2.

Publications

Rising levels of atmospheric oxygen and evolution of Nrf2.

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