My research is utilizing physiological, cellular and molecular biological approaches
to study the adaptive mechanisms of solute homeostasis in fish during environmental
stress. Maintenance of solute balance at appropriate levels is of fundamental importance
in biology. Impairment of solute homeostasis is associated with a variety of environmental
disturbances (e.g., metal exposure, acidification, osmotic challenges) and pathological
states. The long-term focus of my research is to identify and functionally characterize
homeostatic mechanisms allowing fish and other aquatic organisms to survive exposure
to diverse aquatic environments.
My prospective research will address the following broad questions:
What adaptive features of fish epithelia influence tolerance to extreme aquatic environments? Physiological, biochemical and molecular genetic aspects.
I am interested in questions related to the adaptive mechanisms of solute regulation in freshwater fish. There is considerable variability amongst fish species in the ability to regulate ion balance in extreme environments. However, the exact mechanisms underlying these differences remain poorly understood. The potential for physiological adaptation is in part related to variations in the relative abundance of specific ion-transporting cells and the differential expression of membrane transporters in fish epithelia. My research makes use of cell culture and whole animal approaches to characterize the factors controlling the cellular plasticity of epithelial membranes in fish.
What adaptive features influence metal homeostasis during environmental perturbations?
Metals are common constituents of biological systems, playing important roles in various regulatory and catalytic processes. In fish, metal uptake occurs to a large extent through ion transporters on the epithelial surfaces of the gill and gastrointestinal tract. In other organisms, metal-specific transporters and regulators have been implicated in the homeostatic control of cellular metal ions. It is unclear the importance of these ion transport pathways in maintaining metal homeostasis. I am interested in studying the relative importance of these different transport systems in fish and other aquatic organisms. I am currently using cell physiological approaches and surrogate gill models to identify cell-specific metal transport pathways. I hope to gain insight into the role of metal homeostasis in fish health.
What are the biotic and abiotic determinants of metal bioavailability to fish in natural aquatic systems?
At an applied level, I am interested in incorporating this knowledge of metal transport towards the development of tools for assessing the environmental risk of metal contamination in natural aquatic systems. The bioavailability and toxicity of metals are strongly influenced by both biotic and abiotic factors. However, most researchers choose to focus on only one part of this equation. There is great power in combining these approaches to understand the effects of metals in complex aquatic systems. Progress is best achieved by using an integrative approach investigating effects across various levels of biological organization.
López-Duarte, P.C.; Fodrie, J.; Jensen, O.P.; Whitehead, A.W.; Galvez, F.; Dubansky, B.; Able, K.W. Is exposure to Macondo Oil reflected in the otolith chemistry of marsh-resident fish? PLOS One. 2016, 11: 9. e0162699.
Guan, Y., Zhang, G.X., Zhang, S., Domangue, B., Galvez, F. The potential role of polyamines in gill epithelial remodeling during extreme hypoosmotic challenges in the Gulf killifish, Fundulus grandis. Comparative Biochemistry and Physiology. B. 2016, online at doi:10.1016/j.cbpb.2016.01.003.
Singleton, B.; Turner, J.; Walter, L.; Lathan, N.; Thorpe, D.; Ogbevoen, P.; Daye, J.; Alcorn, D.; Wilson, S.; Semien, J.; Richard, T.; Johnson, T.; McCabe, K.; Estrada, J.J.; Galvez, F.; et al. Environmental stress in the Gulf of Mexico and its potential impact on public health. Environmental Research. 2016, 146: 108-115
Brennan, R.; Galvez, F.; Whitehead, A. Reciprocal osmotic challenges reveal mechanisms of divergence in phenotypic plasticity in the killifish Fundulus heteroclitus. Journal of Experimental Biology. 2015, 218: (8), 1212-1222.
Shaw, J.R.; Hampton, T.H.; King, B.L; Whitehead, A.; Galvez, F.; et al. Natural selection canalizes expression variation of environmentally induced plasticity-enabling genes. Molecular Biology and Evolution. 2014, 31: (11), 3002–3015.
Fodrie, F.J.; Able, K.W.; Galvez, F. et al. Integrating organismal and population responses of estuarine fishes to the Macondo spill reveals research priorities in the Gulf of Mexico. BioScience. 2014, 64: (9), 778–788.
Dubansky, B.; Whitehead, A.; Miller, J.T.; Rice, C.D.; Galvez, F. Comment on: “Multitissue Molecular, Genomic, and developmental effects of the Deepwater Horizon Oil Spill on resident Gulf killifish (Fundulus grandis).” Environmental Science and Technology. 2014, 48: (13), 7679–7680.
Whitehead, A.; Zhang, S.; Roach, J.L.; Galvez, F. Common functional targets of adaptive micro- and macro-evolutionary divergence in killifish. Molecular Ecology. 2013, 22: (14), 3780-3796. [Featured in Molecular Ecology 2013; 22, 3656–3658 - News and Views].
Dubansky, B.; Whitehead, A.; Miller, J.T.; Rice, C.D.; Galvez, F. Multitissue Molecular, Genomic, and developmental effects of the Deepwater Horizon Oil Spill on resident Gulf killifish (Fundulus grandis). Environmental Science and Technology 2013, 47: (10), 5074-5082. [Featured by the National Science Foundation, CNN, Los Angeles Times, Science Daily, etc.]
Whitehead, A.; Dubansky, B.; Bodinier, C.; Garcia, T. I.; Miles, S.; Pilley, C.; Raghunathan, V.; Roach, J. L.; Walker, N.; Walter, R. B.; Rice, C. D.; Galvez, F. Reply to Jenkins et al.: Evidence for contaminating oil exposure is closely linked in space and time to biological effects. Proceedings of the National Academy of Sciences of the United States of America 2012: 109, (12), E679-E679.
Brown, C.A.; Galvez, F.; Green, C.C. Embryonic development and metabolic costs in Gulf killifish Fundulus grandis exposed to varying environmental salinities. Fish Physiology and Biochemistry. 2012, 38: (4),1071-1082.
Whitehead, A.; Roach, J.; Zhang, S.; Galvez, F. Salinity-dependent and population-dependent genome regulatory response during osmotic acclimation. Journal of Experimental Biology. 2002, 215: (8), 1293-305.
Whitehead, A.; Dubansky, B.; Bodinier, C.; Barcia, T.I.; Miles, S.; Pilley, C.; Raghunathan, V.; Roach, J.L.; Walker, N.; Walter, R.B.; Rice, C.D.; Galvez, F. Genomic and physiological footprint of the Deepwater Horizon oil spill on resident marsh fishes. Proceedings of the National Academy of Sciences. 2002, 109: 20298-20302. [Featured in NSF.gov, New York Times, Washington Post, Miami Herald, Associated Press, ABC World News, and at least 200 news services; Testified to U.S. House Committee on Natural Resources].
Whitehead, A.; Galvez, F.; Zhang, S.; Oleksiak, M. Functional genomics of physiological plasticity and local adaptation in killifish: an emerging model in environmental genomics. Heredity. 2011, 102: 499-511. [Featured in New Scientist (2010), June 30].