Dr. Jim S. Ballantyne
Professor
Email: jballant@uoguelph.ca
Office: SCIE 3465
Ext: 52708
Lab: SCIE 3407/3408
Ext: 58385
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Profile
My interest in aquatic organisms began at an early age as I grew up fishing on the Rideau River system in Ontario. This was reinforced and focused in my undergraduate and graduate degrees where I developed my interests in physiology and biochemistry. My Ph.D. at the University of British Columbia with Peter Hochachka fixed my interests in the mechanisms of biochemical adaptation. My current research examines the metabolic design of aquatic organisms in both an adaptive and an evolutionary context. Click on "Research Interests" for more information on specific projects.
I was a NSERC University Research Fellow for the first 10 years of my appointment at the University of Guelph. I have been a panel member and Chair of the NSERC Strategic Grants Biosciences panel and am currently a member of the Executive Committee of the Board of Directors of the Huntsman Marine Science Centre in St. Andrews, New Brunswick.
Education
BSc Guelph 1973
MSc Guelph 1976
PhD British Columbia 1981
Research
Applied Research Program: Aquaculture
Funded by two strategic grants (Ballantyne PI) and a project within AQUANET (Networks of Centres of Excellence) (Ballantyne and Moon co-PIs) we have been applying our research expertise to solving problems in the Canadian aquaculture industry. We are currently working on projects with Arctic char, Atlantic salmon, shortnose sturgeon, winter flounder and Atlantic cod
Basic research program:
My basic research program involves investigations of the metabolism of organisms. The following sections list the current interests of myself and those in my laboratory.
Metabolic regulation:
Short-term thyroid hormone effects. We are studying the short term effects of thyroid hormones on mitochondrial metabolism of fish. We have also demonstrated that T2 and T3 act directly on mitochondria rather than acting via the genome. These findings may indicate a novel role for thyroid hormones in mediating certain aspects of mitochondrial metabolism.
The role of proton leak in the metabolism of poilkilothermic organisms. We are examining the magnitude and energetic cost of the mitochondrial proton leak in poikilothermic organisms. The effects of environmental parameters such as temperature and salinity change on the proton leak are under investigation.
Environmental adaptation:
Solute effects on membrane structure and function. A variety of solutes are found at high levels in the cells of marine invertebrates and some fish. Some of these may affect membrane properties. We are examining adaptation of membranes of elasmobranch fishes (shark's skates and rays) to the high level of urea and methylamines found in their tissues. We have shown that elasmobranch mitochondrial membranes are unusual in their phospholipid and fatty acid composition and are now examining how solutes may affect these membranes.
Mechanisms of urea retention in elasmobranch fishes. We are examining how the gills and kidneys of sharks and rays are adapted to retain urea. As the most important osmotically active particle in marine sharks and rays, urea retention plays an important role in the energetics of these fishes. Our research focuses on the membrane structure and the function of the urea transporters of the gills and kidneys of marine and freshwater elasmobranchs. Part of this work is done in collaboration with Dr. P.A Wright (University of Guelph) and Dr. K.Y. Ip (National University of Singapore).
Membrane alterations during metabolic arrest.The profound metabolic arrest experienced by terrestrial snails when deprived of water and food is accompanied by equally substantial changes in mitochondrial membrane structure and function. We are examining the mechanisms involved in membrane modification to permit these organisms to survive such harsh conditions in a state of metabolic arrest..
Temperature adaptation of membranes. We are currently investigating the structure of membranes of cold water adapted marine organisms. These studies are undertaken in the Canadian Arctic at Resolute, Nunavut. Both marine molluscs and freshwater and marine fish are being examined. Thus far these studies indicate unusual membrane fatty acid composition that may be due to dietary fatty acid intake as well as low temperature adaptation. Other laboratory studies conducted in the AQUALAB facility, are being used to determine the design features of membranes of eurythermal membranes and membranes adapted to chronically low temperatures.
Salinity adaptation. We are examining the metabolic and membrane changes associated with salinity adaptation in molluscs and fish. Membrane structural modifications may play an important role in mediating the function of membrane-associated proteins. We are examining such changes in osmoconforming invertebrates and osmoregulating vertebrates (teleost fish). These include investigations of a gastropod mollusc (Coxiella) from the hypersaline lakes of western Australia, anadromous arctic char from the Canadian Arctic as well as brackish water stingrays from Indonesia.
Comparative and evolutionary aspects of metabolism:
Amino acid metabolism. I have shown there are changes in the importance of amino acids as energy sources in the evolution of the vertebrates and molluscs. Our finding that the red muscle mitochondria of all fish examined to date as well as amphibians oxidize glutamine at high rate indicated a contrast with the situation in mammalian muscle which is a net exporter of glutamine and has little capacity for glutamine oxidation. This finding has a broad significance in understanding the metabolism of fishes in general and the evolution of metabolism in the vertebrates. We are examining the mechanisms of glutamine transport and metabolic regulation in teleost fish and elasmobranchs.
Ketone body metabolism. We are also investigating the various roles and importance of ketone bodies in animals. We have established that two tissue specific forms of the enzyme exist in molluscs and fish with differing isomeric specificity. While terrestrial and freshwater molluscs have a well developed ketone body metabolism, marine molluscs do not express the terminal enzyme in the pathway (b-hydroxybutyrate dehydrogenase). Our work in this area involves establishing the role of ketone bodies in molluscs and anoxia tolerant fish.
Elasmobranch metabolism. The metabolism of elasmobranch fishes differs substantially from that of virtually all other vertebrates due to the need to synthesize substantial amounts of urea for osmotic support. One manifestation of this is a reduced reliance on lipid substrates and increased reliance on ketone bodies. We are examining aspects of the role of glutamine in elasmobranch metabolism and its interaction with lipid and ketone body metabolism.
Selected Publications
Lingwood,D., G. Hazauz and J.S. Ballantyne 2005. Regulation of fish gill Na+-K+-ATPase by selective sulfatide-enriched raft partitioning during seawater adaptation. J.Biol. Chem. 280:36545-36550.
Mackie,P., P.A. Wright and J.S. Ballantyne. 2005. Osmoregulation and gene expression of Na+,K+ ATPase in families of Atlantic salmon smolts. Can.J.Fish.Aquat.Sci. .62:2661-2672.
Levesque,H.M., C. Short, T.W. Moon, J.S. Ballantyne, and W.R. Driedzic. 2005. Effects of seasonal temperature and photoperiod on Atlantic cod (Gadus morhua). I. Morphometric parameters and metabolites. Can. J. Fish. Aquat. Sci. 62:2854-2863.
Levesque,H.M., J. Bondy, C. Short, J.S. Ballantyne, W.R. Driedzic and T.W.Moon. 2005. Effects of seasonal temperature and photperiod on Atlantic cod (Gadus morhua) II. Enzymes of intermediary metabolism. Can.J.Fish.Aquat.Sci. 62:2864-2873.
Speers-Roesch,B. and J.S. Ballantyne. 2005. Activities of antioxidant and cytochrome c oxidase in liver of Arctic and temperate teleosts. Comp. Biochem. Physiol. 140A:487-494.
Ballantyne, J. S. 2004. Mitochondria: aerobic and anaerobic design - lessons from molluscs and fishes. Comp.Biochem.Physiol. 139B: 461-467.
Ip, Y. K., D. J. Randall, T. K. T. Kok, C. Barzaghi, P. A. Wright, J. S. Ballantyne, J. M. Wilson, and S. F. Chew. 2004. The giant mudskipper Periophthalmodon schlosseri facilitates active NH 4 + excretion by increasing acid excretion and decreasing NH 3 permeability in the skin. J.Exp.Biol. 207: 787-801.
3. Lingwood, D. D., L. J. Fisher, J. W. Callanhan, and J. S. Ballantyne. 2004. Sulfatide and Na + -K + -ATPase: a salinity-sensitive relationship in the gill basolateral membrane of rainbow trout. J.Membrane Biol. 200: 1-8.
Tam, W. L., W. P. Wong, A. M. Loong, K. C. Hiong, S. F. Chew, J. S. Ballantyne, and Y. K. Ip. 2003. The osmotic response of the Asian freshwater stingray (Himantura signifer) to increased salinity: a comparision with marine (Taeniura lymma) abd Amazonian freshwater (Potamotrygon motoro) stingrays. J.Exp.Biol. 206: 2931-2940.
Ip, Y. K., W. L. Tam, W. P. Wong, A. M. Loong, K. C. Hong, J. S. Ballantyne, and S. F. Chew. 2003. A comparison of the effects of exposure to environmental ammonia on the Asian freshwater stingray Himantura signifer and the Amazonian freshwater stingray Potamotrygon motoro. J.Exp.Biol. 206: 3625-3633.
Jarvis, P. L. and J. S. Ballantyne. 2003. Metabolic responses to salinity acclimation in juvenile shortnose sturgeon Acipenser brevirostrum. Aquaculture 219: 891-909.
Morgan, R. L., J. S. Ballantyne, and P. A. Wright. 2003. Regulation of a renal urea transport with salinity in a marine elasmobranch Raja erinacea. J.Exp.Biol. 206: 3285-3292.
Morgan, R. L., J. S. Ballantyne, and P. A. Wright. 2003. Urea transporter in kidney brush-border membrane vesicles from a marine elasmobranch, Raja erinacea. J.Exp.Biol. 206: 3293-3202.
Shahsavarani, A., Z.C. Thomas, J.S. Ballantyne and P.A. Wright. 2002. A novel technique for the separation of yolk from the developing embryonic tissue in a teleost fish, Oncorhynchus mykiss. Fish. Physiol. Biochem. 24:321-326.
Fines, G.A., J.S. Ballantyne and P.A. Wright. 2001. Active urea transport and an unusual basolateral membrane composition in the gills of a marine elasmobranch Am. J. Physiol. 280:R16-R24200
Fudge,D.S., Ballantyne, J.S. and E.D. Stevens. 2001. A test of biochemical symmorphosis in a heterothermic tissue: bluefin tuna white muscle.. Am. J. Physiol. 280:R108-R1142001
Barton, K.N., M.M. Buhr, and J.S. Ballantyne. 1999. Effects of urea and trimethylamine N-oxide on fluidity of liposomes and erythrocyte membranes of an elasmobranch (Raja erinacea). Am. J. Physiol. 276: R397-R406.
Gillis, T.E. and J.S. Ballantyne. 1999. Mitochondrial membrane composition of two Arctic marine bivalve molluscs, Serripes groenlandicus and Mya truncata. Lipids 34:53-58.
Fudge, D.S., E.D. Stevens, and J.S. Ballantyne. 1998. No evidence for homeoviscous adaptation in a heterothermic tissue: tuna heat exchangers. Am. J. Physiol. 275:R818-R823.
Stuart, J.A., T.E. Gillis, and J.S. Ballantyne. 1998.Compositional correlates of metabolic depression in mitochondrial membranes of an estivating snail, Cepaea nemoralis. Am. J. Physiol. 275:R1977-R1982.
Stuart, J.A., T.E. Gillis, and J.S. Ballantyne. 1998. Remodeling of phospholipid fatty acids in mitochondrial membranes of estivating snails. Lipids 33: 787-793.
Ballantyne, J.S. 1997. Jaws, the inside story. The metabolism of elasmobranch fishes. Comp. Biochem. Physiol. 118B: 703-742.
Teaching
IBIO*4010 Adaptational Physiology
ZOO*4300 Marine Biology and Oceanography
ZOO*4540 Marine and Freshwater Research I
ZOO*4560 Marine and Freshwater Adaptations
ZOO*4600 Tropical Ecology*
*Co-teaches course with Paul D.N. Hebert
Grad Students
Boutilier, Ryan (MSc)
Castanon Escobar, Rosario (MSc Aquaculture)
Fraser, David (MSc)
Robinson, Jake (PhD)
Shapiro, Noah (MSc)