title: Turtle anoxia tolerance: Biochemistry and gene regulation.
abstract: BACKGROUND
  While oxygen limitation can be extremely damaging for many animals, some vertebrates have perfected anaerobic survival. Freshwater turtles belonging to the Trachemys and Chrysemys genera, for example, can survive many weeks without oxygen, and as such are commonly used as model animals for vertebrate anoxia tolerance.
  
  
  METHODS
  In the present review we discuss the recent advances made in understanding the biochemical and molecular nature of natural anoxia tolerance of freshwater turtles.
  
  
  CONCLUSIONS
  Research in recent years has shown that activation of several important pathways occurs in response to anoxia in turtles, including those that function in the stress response, cell cycle arrest, inhibition of gene expression and metabolism. These likely contribute to anoxia tolerance in turtle tissues by minimizing cell damage in response to anoxia, as well as facilitating metabolic rate depression.
  
  
  CONCLUSIONS
  The research discussed in the present review contributes to the understanding of how freshwater turtles can survive without oxygen for prolonged periods of time. This could also improve understanding of the molecular nature of hypoxic/ischemic injuries in mammalian tissues and suggest potential ways to avoid these.
authors: Institute of Biochemistry, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario K1S 5B6, Canada; Department of Biology, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario K1S 5B6, Canada. Electronic address: krivoruchko@gmail.com.
authors: Anastasia
authors: A
authors: Krivoruchko
authors: Institute of Biochemistry, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario K1S 5B6, Canada; Department of Biology, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario K1S 5B6, Canada.
authors: Kenneth B
authors: KB
authors: Storey
mesh_terms: D000222:Adaptation, Physiological; D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D004734:Energy Metabolism; D005786:Gene Expression Regulation; D000860:Hypoxia / Q000235:genetics / Q000378:metabolism* / Q000503:physiopathology; D018384:Oxidative Stress; D010100:Oxygen / Q000378:metabolism*; D015398:Signal Transduction; D014157:Transcription Factors / Q000378:metabolism; D014426:Turtles / Q000235:genetics / Q000378:metabolism*
chemical_list: D000975:Antioxidants; D014157:Transcription Factors; D010100:Oxygen
keywords: FoxO; HDAC; Heat shock response; NF-kappaB; Unfolded protein response; p53