title: Whales use distinct strategies to counteract solar ultraviolet radiation.
abstract: A current threat to the marine ecosystem is the high level of solar ultraviolet radiation (UV). Large whales have recently been shown to suffer sun-induced skin damage from continuous UV exposure. Genotoxic consequences of such exposure remain unknown for these long-lived marine species, as does their capacity to counteract UV-induced insults. We show that UV exposure induces mitochondrial DNA damage in the skin of seasonally sympatric fin, sperm, and blue whales and that this damage accumulates with age. However, counteractive molecular mechanisms are markedly different between species. For example, sperm whales, a species that remains for long periods at the sea surface, activate genotoxic stress pathways in response to UV exposure whereas the paler blue whale relies on increased pigmentation as the season progresses. Our study also shows that whales can modulate their responses to fluctuating levels of UV, and that different evolutionary constraints may have shaped their response strategies.
authors.affiliation: Institute of Zoology, Zoological Society of London, UK.
authors.forename: Laura M
authors.initials: LM
authors.lastname: Martinez-Levasseur
authors.forename: Mark A
authors.initials: MA
authors.lastname: Birch-Machin
authors.forename: Amy
authors.initials: A
authors.lastname: Bowman
authors.forename: Diane
authors.initials: D
authors.lastname: Gendron
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Weatherhead
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Knell
authors.forename: Karina
authors.initials: K
authors.lastname: Acevedo-Whitehouse
mesh_terms: D000818:Animals; D004249:DNA Damage / Q000235:genetics* / Q000528:radiation effects*; D020543:Proteome / Q000378:metabolism; D012867:Skin / Q000503:physiopathology* / Q000528:radiation effects*; D013045:Species Specificity; D050661:Sperm Whale / Q000502:physiology*; D013472:Sunlight / Q000009:adverse effects*; D014466:Ultraviolet Rays / Q000009:adverse effects*
chemical_list: D020543:Proteome