• myGriffith
    • Staff portal
    • Contact Us⌄
      • Future student enquiries 1800 677 728
      • Current student enquiries 1800 154 055
      • International enquiries +61 7 3735 6425
      • General enquiries 07 3735 7111
      • Online enquiries
      • Staff phonebook
    View Item 
    •   Home
    • Griffith Research Online
    • Journal articles
    • View Item
    • Home
    • Griffith Research Online
    • Journal articles
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    Browse

  • All of Griffith Research Online
    • Communities & Collections
    • Authors
    • By Issue Date
    • Titles
  • This Collection
    • Authors
    • By Issue Date
    • Titles
  • Statistics

  • Most Popular Items
  • Statistics by Country
  • Most Popular Authors
  • Support

  • Contact us
  • FAQs
  • Admin login

  • Login
  • Compensatory proteome adjustments imply tissue-specific structural and metabolic reorganization following episodic hypoxia or anoxia in the epaulette shark (Hemiscyllium ocellatum)

    Author(s)
    Dowd, WW
    Renshaw, GMC
    Cech, JJ
    Kültz, D
    Griffith University Author(s)
    Renshaw, Gillian M.
    Year published
    2010
    Metadata
    Show full item record
    Abstract
    The epaulette shark (Hemiscyllium ocellatum) represents an ancestral vertebrate model of episodic hypoxia and anoxia tolerance at tropical temperatures. We used two-dimensional gel electrophoresis and mass spectrometry-based proteomics approaches, combined with a suite of physiological measures, to characterize this species' responses to 1) one episode of anoxia plus normoxic recovery, 2) one episode of severe hypoxia plus recovery, or 3) two episodes of severe hypoxia plus recovery. We examined these responses in the cerebellum and rectal gland, two tissues with high ATP requirements. Sharks maintained plasma ionic homeostasis ...
    View more >
    The epaulette shark (Hemiscyllium ocellatum) represents an ancestral vertebrate model of episodic hypoxia and anoxia tolerance at tropical temperatures. We used two-dimensional gel electrophoresis and mass spectrometry-based proteomics approaches, combined with a suite of physiological measures, to characterize this species' responses to 1) one episode of anoxia plus normoxic recovery, 2) one episode of severe hypoxia plus recovery, or 3) two episodes of severe hypoxia plus recovery. We examined these responses in the cerebellum and rectal gland, two tissues with high ATP requirements. Sharks maintained plasma ionic homeostasis following all treatments, and activities of Na+/K+-ATPase and caspase 3/7 in both tissues were unchanged. Oxygen lack and reoxygenation elicited subtle adjustments in the proteome. Hypoxia led to more extensive proteome responses than anoxia in both tissues. The cerebellum and rectal gland exhibited treatment-specific responses to oxygen limitation consistent with one or more of several strategies: 1) neurotransmitter and receptor downregulation in cerebellum to prevent excitotoxicity, 2) cytoskeletal/membrane reorganization, 3) metabolic reorganization and more efficient intracellular energy shuttling that are more consistent with sustained ATP turnover than with long-term metabolic depression, 4) detoxification of metabolic byproducts and oxidative stress in light of continued metabolic activity, particularly following hypoxia in rectal gland, and 5) activation of prosurvival signaling. We hypothesize that neuronal morphological changes facilitate prolonged protection from excitotoxicity via dendritic spine remodeling in cerebellum (i.e., synaptic structural plasticity). These results recapitulate several highly conserved themes in the anoxia and hypoxia tolerance, preconditioning, and oxidative stress literature in a single system. In addition, several of the identified pathways and proteins suggest potentially novel mechanisms for enhancing anoxia or hypoxia tolerance in vertebrates. Overall, our data show that episodic hypoxic or anoxic exposure and recovery in the epaulette shark amplifies a constitutive suite of compensatory mechanisms that further prepares them for subsequent insults.
    View less >
    Journal Title
    Physiological Genomics
    Volume
    42
    Issue
    1
    DOI
    https://doi.org/10.1152/physiolgenomics.00176.2009
    Copyright Statement
    Self-archiving of the author-manuscript version is not yet supported by this journal. Please refer to the journal link for access to the definitive, published version or contact the author[s] for more information.
    Subject
    Medical Physiology not elsewhere classified
    Medical Physiology
    Publication URI
    http://hdl.handle.net/10072/35767
    Collection
    • Journal articles

    Footer

    Disclaimer

    • Privacy policy
    • Copyright matters
    • CRICOS Provider - 00233E

    Tagline

    • Gold Coast
    • Logan
    • Brisbane - Queensland, Australia
    First Peoples of Australia
    • Aboriginal
    • Torres Strait Islander