title: Thermal Preference Ranges Correlate with Stable Signals of Universal Stress Markers in Lake Baikal Endemic and Holarctic Amphipods.
abstract: Temperature is the most pervasive abiotic environmental factor for aquatic organisms. Fluctuations in temperature range lead to changes in metabolic performance. Here, we aimed to identify whether surpassing the thermal preference zones is correlated with shifts in universal cellular stress markers of protein integrity, responses to oxidative stress and lactate content, as indicators of anaerobic metabolism. Exposure of the Lake Baikal endemic amphipod species Eulimnogammarus verrucosus (Gerstfeldt, 1858), Ommatogammarus flavus (Dybowski, 1874) and of the Holarctic amphipod Gammarus lacustris Sars 1863 (Amphipoda, Crustacea) to increasing temperatures resulted in elevated heat shock protein 70 (Hsp70) and lactate content, elevated antioxidant enzyme activities (i.e., catalase and peroxidase), and reduced lactate dehydrogenase and glutathione S-transferase activities. Thus, the zone of stability (absence of any significant changes) of the studied molecular and biochemical markers correlated with the behaviorally preferred temperatures. We conclude that the thermal behavioral responses of the studied amphipods are directly related to metabolic processes at the cellular level. Thus, the determined thermal ranges may possibly correspond to the thermal optima. This relationship between species-specific behavioral reactions and stress response metabolism may have significant ecological consequences that result in a thermal zone-specific distribution (i.e., depths, feed spectrum, etc.) of species. As a consequence, by separating species with different temperature preferences, interspecific competition is reduced, which, in turn, increases a species' Darwinian fitness in its environment.
authors.affiliation: Institute of Biology at Irkutsk State University, Irkutsk, Russia.|Baikal Research Centre, Irkutsk, Russia.
authors.forename: Denis
authors.initials: D
authors.lastname: Axenov-Gribanov
authors.affiliation: Institute of Biology at Irkutsk State University, Irkutsk, Russia.
authors.forename: Daria
authors.initials: D
authors.lastname: Bedulina
authors.affiliation: Institute of Biology at Irkutsk State University, Irkutsk, Russia.|Baikal Research Centre, Irkutsk, Russia.
authors.forename: Zhanna
authors.initials: Z
authors.lastname: Shatilina
authors.affiliation: Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany.|University of Bremen, Bremen, Germany.
authors.forename: Lena
authors.initials: L
authors.lastname: Jakob
authors.affiliation: Institute of Biology at Irkutsk State University, Irkutsk, Russia.
authors.forename: Kseniya
authors.initials: K
authors.lastname: Vereshchagina
authors.affiliation: Institute of Biology at Irkutsk State University, Irkutsk, Russia.
authors.forename: Yulia
authors.initials: Y
authors.lastname: Lubyaga
authors.affiliation: Institute of Biology at Irkutsk State University, Irkutsk, Russia.
authors.forename: Anton
authors.initials: A
authors.lastname: Gurkov
authors.affiliation: Institute of Biology at Irkutsk State University, Irkutsk, Russia.
authors.forename: Ekaterina
authors.initials: E
authors.lastname: Shchapova
authors.affiliation: Helmholtz Centre for Environmental Research-UFZ, Leipzig, Germany.
authors.forename: Till
authors.initials: T
authors.lastname: Luckenbach
authors.affiliation: Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany.
authors.forename: Magnus
authors.initials: M
authors.lastname: Lucassen
authors.affiliation: Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany.
authors.forename: Franz Josef
authors.initials: FJ
authors.lastname: Sartoris
authors.affiliation: Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany.|University of Bremen, Bremen, Germany.
authors.forename: Hans-Otto
authors.initials: HO
authors.lastname: Pörtner
authors.affiliation: Institute of Biology at Irkutsk State University, Irkutsk, Russia.
authors.forename: Maxim
authors.initials: M
authors.lastname: Timofeyev
mesh_terms: D033304:Amphipoda / Q000145:classification / Q000502:physiology*; D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D015415:Biomarkers / Q000378:metabolism*; D017753:Ecosystem; D018840:HSP70 Heat-Shock Proteins / Q000378:metabolism; D019344:Lactic Acid / Q000378:metabolism; D060106:Lakes; D013045:Species Specificity; D013312:Stress, Physiological; D013696:Temperature
chemical_list: D000975:Antioxidants; D015415:Biomarkers; D018840:HSP70 Heat-Shock Proteins; D019344:Lactic Acid