Proteomic and physiological responses of leopard sharks (Triakis semifasciata) to salinity change

W W Dowd; B N Harris; J J Cech, Jr; D Kültz

doi:10.1242/jeb.031781

Back

Proteomic and physiological responses of leopard sharks (Triakis semifasciata) to salinity change

Journal article

Open access

Peer reviewed

Proteomic and physiological responses of leopard sharks (Triakis semifasciata) to salinity change

W W Dowd, B N Harris, J J Cech, Jr and D Kültz

Journal of experimental biology, Vol.213(2), pp.210-224

01/15/2010

DOI: https://doi.org/10.1242/jeb.031781

PMID: 20038654

Files and links (2)

pdf

Proteomic_dowd871.40 kBDownload View

Open Access

url

https://doi.org/10.1242/jeb.031781View

Published (Version of record) Open

Abstract

Adaptation, Physiological - drug effects

Adaptation, Physiological - physiology

Behavior, Animal

Dose-Response Relationship, Drug

Gene Expression Profiling

Gene Expression Regulation - physiology

Gills - metabolism

Salt Gland - metabolism

Seawater - chemistry

Sharks - physiology

Sodium Chloride - chemistry

Sodium Chloride - pharmacology

Water-Electrolyte Balance - physiology

Partially euryhaline elasmobranchs may tolerate physiologically challenging, variable salinity conditions in estuaries as a trade-off to reduce predation risk or to gain access to abundant food resources. To further understand these trade-offs and to evaluate the underlying mechanisms, we examined the responses of juvenile leopard sharks to salinity changes using a suite of measurements at multiple organizational levels: gill and rectal gland proteomes (using 2-D gel electrophoresis and tandem mass spectrometry), tissue biochemistry (Na(+)/K(+)-ATPase, caspase 3/7 and chymotrypsin-like proteasome activities), organismal physiology (hematology, plasma composition, muscle moisture) and individual behavior. Our proteomics results reveal coordinated molecular responses to low salinity - several of which are common to both rectal gland and gill - including changes in amino acid and inositol (i.e. osmolyte) metabolism, energy metabolism and proteins related to transcription, translation and protein degradation. Overall, leopard sharks employ a strategy of maintaining plasma urea, ion concentrations and Na(+)/K(+)-ATPase activities in the short-term, possibly because they rarely spend extended periods in low salinity conditions in the wild, but the sharks osmoconform to the surrounding conditions by 3 weeks. We found no evidence of apoptosis at the time points tested, while both tissues exhibited proteomic changes related to the cytoskeleton, suggesting that leopard sharks remodel existing osmoregulatory epithelial cells and activate physiological acclimatory responses to solve the problems posed by low salinity exposure. The behavioral measurements reveal increased activity in the lowest salinity in the short-term, while activity decreased in the lowest salinity in the long-term. Our data suggest that physiological/behavioral trade-offs are involved in using estuarine habitats, and pathway modeling implicates tumor necrosis factor alpha (TNFalpha) as a key node of the elasmobranch hyposmotic response network.

Metrics

12 Record Views

Details

Title: Proteomic and physiological responses of leopard sharks (Triakis semifasciata) to salinity change
Creators: W W Dowd - Washington State University, Biological Sciences, School of
B N Harris
J J Cech, Jr
D Kültz
Publication Details: Journal of experimental biology, Vol.213(2), pp.210-224
Academic Unit: Biological Sciences, School of
Identifiers: 99900591861701842
Language: English
Resource Type: Journal article