Radiation and the regulatory landscape of neo2-Darwinism.
Several recently revealed features of eukaryotic genomes were not predicted by earlier evolutionary paradigms, including the relatively small number of genes, the very large amounts of non-functional code and its quarantine in heterochromatin, the remarkable conservation of many functionally important genes across relatively enormous phylogenetic distances, and the prevalence of extra-genomic information associated with chromatin structure and histone proteins. All of these emphasize a paramount role for regulatory evolution, which is further reinforced by recent perspectives highlighting even higher-order regulation governing epigenetics and development (EVO-DEVO). Modern neo2-Darwinism, with its emphasis on regulatory mechanisms and regulatory evolution provides new vision for understanding radiation biology, particularly because free radicals and redox states are central to many regulatory mechanisms and free radicals generated by radiation mimic and amplify endogenous signalling. This paper explores some of these aspects and their implications for low-dose radiation biology.
Rollo
C David
CD
Department of Biology, Life Sciences Building, 1280 Main St. West, Hamilton, Ont., Canada L8S 4K1. rollocd@mcmaster.ca
D000818:Animals; D005075:Biological Evolution; D002843:Chromatin / Q000235:genetics / Q000378:metabolism / Q000528:radiation effects; D019175:DNA Methylation; D044127:Epigenesis, Genetic; D016678:Genome / Q000528:radiation effects; D018841:HSP90 Heat-Shock Proteins / Q000378:metabolism; D006801:Humans; D008074:Lipoproteins / Q000378:metabolism; D008954:Models, Biological; D009247:NADH, NADPH Oxidoreductases / Q000378:metabolism; D010084:Oxidation-Reduction; D011853:Radiobiology; D017382:Reactive Oxygen Species / Q000378:metabolism; D015398:Signal Transduction
D002843:Chromatin; D018841:HSP90 Heat-Shock Proteins; D008074:Lipoproteins; D017382:Reactive Oxygen Species; D009247:NADH, NADPH Oxidoreductases