Book chapter
Physiological compensation in response to environmental challenges in three shark species: Molecular to organismal aspects
Dissertation Abstracts International. Vol. 70, no. 11, suppl. B, 239 p. 2009, pp.239-239
01/01/2009
Handle:
https://hdl.handle.net/2376/117222
Abstract
This dissertation examines molecular to organismal physiological mechanisms used by three shark species to cope with physiological challenges faced in their environments. Using mass spectrometry-based proteomics in concert with other physiological approaches, I examine physiological responses to (i) indirect salt loading following feeding in the spiny dogfish, (ii) anoxic and hypoxic preconditioning in the epaulette shark, and (iii) osmoregulatory challenge due to salinity change in estuaries in the leopard shark. After feeding, the dogfish rectal gland exhibits upregulation of several proteins involved in maintaining the cellular supply of energy, most likely to fuel the costly Na super(+)/K super(+) ATPase pumps that drive salt excretion. Other upregulated proteins coordinate organization of the cytoskeleton. In epaulette sharks, low oxygen exposure and reoxygenation elicit coordinated--though relatively minor in magnitude--adjustments in proteins related to energy production and consumption, oxidative stress amelioration, and reorganization of the cytoskeleton. Hypoxic/anoxic preconditioning in the epaulette shark appears to amplify a constitutive suite of protective mechanisms. In the leopard shark, lags in organismal osmoregulatory mechanisms coincide with increases in activity in the short-term, followed by a long-term reduction of activity. Leopard shark gill and rectal gland exhibit modified expression patterns of proteins involved in cellular energy metabolism, osmolyte accumulation, and regulation of protein degradation pathways, and the data support reorganization of existing cells rather than osmoregulatory cell turnover. Overall, this research contributes to our understanding of the mechanisms underlying interactions/tradeoffs among physiology, behavior, and ecology in animals inhabiting dynamic, potentially stressful environments.
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Details
- Title
- Physiological compensation in response to environmental challenges in three shark species: Molecular to organismal aspects
- Creators
- William Wesley Dowd
- Publication Details
- Dissertation Abstracts International. Vol. 70, no. 11, suppl. B, 239 p. 2009, pp.239-239
- Academic Unit
- Biological Sciences, School of
- Identifiers
- 99900582338101842
- Language
- English
- Resource Type
- Book chapter