As a senior undergraduate research student at McMaster University, I worked in the lab of Dr. Chris Wood and conducted experiments on ammonia transport across the gills of rainbow trout. This led me to graduate studies at the University of British Columbia under the supervision of Dr. Dave Randall. There I continued studying gas exchange and ion transport in fish. As a postdoctoral fellow at the University of Ottawa, I worked with Drs. Tom Moon and Steve Perry on glucose metabolism. Later I studied mammalian kidney metabolism at NIH as a postdoctoral fellow working with Dr. Mark Knepper. The research in my lab is now focused on how fish and other aquatic animals cope with environmental challenges, with particular interests in amphibious fishes and early life stages.
- B.Sc. - McMaster
- Ph.D. - UBC
Research in my laboratory is focused on osmoregulation and respiration in aquatic animals. I am interested in how animals maintain homeostasis with changes in the external environment. We study the interaction between the animal and its environment from early development to adults in fish and amphibians.
A Fish Out of Water
Amphibious fishes spend part of their life out of water, either daily, seasonally or at a specific life stage. Early work explored the various air breathing organs that amphibious fish use to respire out of water. Much less is know about amphibious fish that respire through the skin. Our work is focused on an unusual amphibious fish that appears to use the skin as the primary respiratory surface when on land. The self-fertilizing, hermaphroditic mangrove rivulus Kryptolebias marmoratus inhabits mangrove forests of the southern US and South/Central America. These tiny fish (~100mg) tolerate a wide range in water temperature, pH, salinity, oxygen, hydrogen sulfide, as well as prolonged air exposure. What strategies do they use to cope with life out of water? We discovered that rivulus excrete gaseous NH3 across the skin during air exposure, a nitrogen excretion strategy similar to terrestrial gastropods and isopods. The skin is also an important site of ion and water exchange in air-exposed rivulus. Gill morphology is reversibly remodelled when the fish move between water and land. But how does gill remodelling impact respiration when rivulus return to water? Why do rivulus leave water (emerse)? Why are some fish able to survive out of water for longer periods than others? These and other questions are currently under investigation in the lab, as well as in the field (Belize).
Early Developmental Plasticity
The early environment surrounding a developing embryo often shapes the adult morphology, physiology and behaviour, in other words the developmental process is plastic. We are interested in how water temperature and/or oxygen levels during critical windows of early zebrafish development alter the long-term thermal and hypoxia tolerance of the adult fish. We are also interested in whether developmental plasticity or adult acclimation both influence thermal preference in eurythermal mangrove rivulus. As well, mangrove rivulus embryos survive and hatch out of water, a possible physiological advantage because air holds ~30x more oxygen than water. We are studying the developmental consequences of early air exposure in mangrove rivulus. These and other projects address the fundamental relationship between genetic and environmental influences on the adult phenotype.
Although fish generate and excrete ammonia, elevated ammonia in the environment can be a deadly poison. We are studying pathways involved in ammonia detoxification. Brain glutamine synthetase is an important enzyme involved in reducing ammonia levels. Alternative nitrogen excretion pathways may also be effective in reducing the uptake of ammonia and/or eliminating excess tissue ammonia. We are studying a new class of ammonia transporters belonging to the Rh family of proteins. Rh genes are upregulated in the gills, kidney and skin of mangrove rivulus, carp, goldfish and trout in response to environmental stress. Work is underway to understand how these proteins function and if they are involved in ammonia excretion.
- McFarlane, W.M. Rossi, G.S. and Wright, P.A. 2019. Amphibious fish “get a jump” on terrestrial locomotor performance after exercise training on land. J. exp. Biol. 222, doi: 10.1242/jeb.213348 (featured article in Hakai Magazine).
- Rossi, G.S., Cochrane, P.V., Tunnah, L. and Wright, P.A. 2019. Aging impacts phenotypic flexibility in an air-acclimated amphibious fish. J. Comp. Phyisol. doi.org/10.1007/s00360-019-01234-8.
- Levesque, K.D., †Wright, P.A. and †Bernier, N.J. († joint senior authors). 2019. Cross-talk without cross-tolerance: Effect of rearing temperature on the hypoxia response of embryonic zebrafish. Physiol. Biochem. Physiol. 92, 349-364.
- Yin-Liao, I., Wright, P.A. and Laberge, F. 2019. Factors affecting terrestrial movement in the amphibious mangrove rivulus (Kryptolebias marmoratus). J. Fish Biol. (in press)
- Rossi, G.S., Tunnah, L., Martin, K.E., Turko, A.J., Taylor, D.S., Currie, S. and Wright, P.A. 2019. Mangrove fishes rely on emersion behaviour and physiological tolerance to persist in sulfidic environments. Physiol. Biochem. Zool. 92, 316-325.
- Blanchard, T.S., Whitehead, A., dong, Y.W. and Wright, P.A. 2019. Phenotypic flexibility in respiratory traits is associated with improved aerial respiration in an amphibious fish out of water. J. exp. Biol. 222, doi: 10.1242/jeb.186486 (featured article in “Inside JEB” in same issue).
- Cochrane, P.V., Rossi, G.S., Tunnah, L., Jonz, M.G. and Wright, P.A. 2019. Hydrogen sulphide toxicity and the importance of amphibious behaviour in mangrove fish inhabiting sulphide-rich habitats. J. Comp. Physiol. B 189, 223-235.
- Livingston, M.D., Turko, A.J., Wilson, J.M. and Wright, P.A. 2018. Widespread use of ammonia volatilization in amphibious Aplocheiloid killifishes. Proc. R. Soc. B. doi: 10.1098/ rspb. 2018. 1496.285 (featured article in “Outside JEB”, vol. 221).
- Rossi, G.S., Turko, A.J. and Wright, P.A. 2018. Oxygen drives skeletal muscle remodelling in an amphibious fish out of water. J. exp. Biol. 221 DOI: 10.1242/jeb.180257
- Livingston, M.D., Turko, A.J., Wilson, J.M. and Wright, P.A. 2018. Widespread use of ammonia volatilization in amphibious Aplocheiloid Killifishes. Proc. R Soc. B DOI:10.1098/rspb.2018.1496.285
- Sutton, A.O., Turko, A.J., McLaughlin, R.L. and Wright, P.A. 2018. Behavioural and physiological responses of an amphibious, euryhaline mangrove fish to acute salinity exposure. Copeia 106 (2): 305-311.
- Turko, A.J., Tatarenkov, A., Currie, S., Earley, R.L., Platek, A., Taylor, D.S. and Wright, P.A. 2018. Emersion behaviour underlies variation in aquatic respiratory function in the amphibious fish Kryptolebias marmoratus. J. exp. Biol. 221, jeb168039. Doi:10.1242/jeb.168039.
- Turko, A.J. Kültz, D. Fudge, D., Croll, R.P., Smith, F. Stoyek, M.R. and Wright, P.A. 2017. Skeletal stiffening in an amphibious fish out of water is a response to increased body weight. J. exp. Biol. 220, 3621-3631.
- Wells, M. and Wright, P.A. 2017. Do not eat your kids: Embryonic kin recognition in an amphibious fish. Behav. Ecol. Sociobiol. 71, 140 (DOI 10.1007/s00265-017-2360-y).
- Heffell, Q., Turko, A.J. and Wright, P.A. 2017. Dermal drinking: Skin water permeability and skin thickness is plastic in the amphibious mangrove rivulus Kryptolebias marmoratus out of water. J. Comp. Physiol. B. DOI 10.1007/s00360-017-1123-4.
- Zimmer, A.M., Wright, P.A. and Wood, C.M. 2017. Ammonia and urea handling by early life stages of fish. J. exp. Biol. 220, 3843-3855.
- Platek, A., Turko, A.J., Donini, A., Kelly, S. and Wright, P.A. 2017. Environmental calcium regulates gill remodeling in an euryhaline teleost fish. J Exp Zool A Ecol Integr Physiol. 327 (2-3), 139-142.
- Blewett, T.A., Simon, R.A., Turko, A.J. and Wright, P.A. 2017. Copper alters behaviour and gill morphology in the amphibious fish (Kryptolebias marmoratus). Aquat. Tox. 189, 25-30.
- Zimmer, A.M., Wilson, J.M., Wright, P.A., Hiroi, J. and Wood, C.M. 2017. Different mechanisms of Na+ uptake and ammonia excretion by the gill and yolk sac epithelium of early life stage rainbow trout. J. exp. Biol. 220, 775-786.
- Brunt, E., Turko, A.J., Scott, G.R. and Wright, P.A. 2016. Amphibious fish jump better on land after acclimation to a terrestrial environment. J. exp. Biol. 219, 3204-3207.
- Wright, P.A. and Turko, A.J. 2016. Amphibious fishes: evolution and phenotypic plasticity. J. exp. Biol. 219, 2245-2259.
- Wright, P.A., Wood, C.M., Hiroi, J. and Wilson, J.M. 2016. (Uncommon) Mechanisms of branchial ammonia excretion in the common carp (Cyprinus carpio) in response to environmentally induced metabolic acidiosis. Physiol. Biochem. Zool. 89, 26-40.
- Wright, P.A., Wood, C.M., Hiroi, J. and Wilson, J.M. 2016. (Uncommon) Mechanisms of branchial ammonia excretion in the common carp (Cyprinus carpio) in response to environmentally induced metabolic acidiosis. Physiol. Biochem. Zool. 89, 26-40
- Louise Tunnah (PhD)
- Giulia Rossi (PhD)
- Paige Cochrane (MSc)