title: Seasonal variations of cellular stress response in the heart and gastrocnemius muscle of the water frog (Pelophylax ridibundus).
abstract: The present study aimed to investigate the seasonal cellular stress response in the heart and the gastrocnemius muscle of the amphibian Pelophylax ridibundus (former name Rana ridibunda) during an 8 month acclimatization period in the field. Processes studied included heat shock protein expression and protein kinase activation. The cellular stress response was addressed through the expression of Hsp70 and Hsp90 and the phosphorylation of stress-activated protein kinases and particularly p38 mitogen-activated protein kinase (p38 MAPK), the extracellular signal-regulated kinases (ERK-1/2) and c-Jun N-terminal kinases (JNK1/2/3). Due to a general metabolic depression during winter hibernation, the induction of Hsp70 and Hsp90 and the phosphorylation of p38 MAPK, JNKs and ERKs are retained at low levels of expression in the examined tissues of P. ridibundus. Recovery from hibernation induces increased levels of the specific proteins, probably providing stamina to the animals during their arousal.
authors.affiliation: Laboratory of Animal Physiology, Department of Zoology, Faculty of Sciences, School of Biology, University of Thessaloniki, GR-54124 Thessaloniki, Greece.
authors.forename: Konstantinos
authors.initials: K
authors.lastname: Feidantsis
authors.forename: Andreas
authors.initials: A
authors.lastname: Anestis
authors.forename: Eleni
authors.initials: E
authors.lastname: Vasara
authors.forename: Pasqualina
authors.initials: P
authors.lastname: Kyriakopoulou-Sklavounou
authors.forename: Basile
authors.initials: B
authors.lastname: Michaelidis
mesh_terms: D000222:Adaptation, Physiological; D029845:Amphibian Proteins / Q000378:metabolism; D000818:Animals; D049628:Body Size; D001835:Body Weight; D018840:HSP70 Heat-Shock Proteins / Q000378:metabolism; D018841:HSP90 Heat-Shock Proteins / Q000378:metabolism; D006321:Heart / Q000502:physiology*; D006605:Hibernation / Q000502:physiology; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D018482:Muscle, Skeletal / Q000166:cytology / Q000378:metabolism* / Q000502:physiology; D009206:Myocardium / Q000166:cytology / Q000378:metabolism*; D010766:Phosphorylation; D011499:Protein Processing, Post-Translational; D011898:Ranidae; D012621:Seasons; D013312:Stress, Physiological
chemical_list: D029845:Amphibian Proteins; D018840:HSP70 Heat-Shock Proteins; D018841:HSP90 Heat-Shock Proteins; D020928:Mitogen-Activated Protein Kinases