Euryhaline fishes are capable of living in wide range of environmental salinity (e.g. freshwater and seawater). They often also have high tolerance to other types of environmental stress (cross-tolerance). We are interested in how euryhaline fishes acclimate to osmotic stress at the cellular and whole organism levels. Because fish gills are in direct contact with the external aquatic environment and responsible for many vital physiological functions, including osmoregulation, they represent an excellent target tissue for studying mechanisms of osmotic stress acclimation. Therefore most of our studies focus on in-depth analysis of environmental stress response mechanisms in fish gills and gill cells. However, when attempting to model whole organisms responses to environmental stress we also include other tissues in our analyses.

Because fishes are aquatic vertebrates abiotic environmental parameters such as osmolality, temperature, pH, oxygen concentration, etc. can be easily controlled during in vivo experiments with gill cells of live fish. This feature represents an important experimental advantage over mammalian kidney cells. Much is known about effector mechanisms of osmoregulation in fish gill cells but we know very little about the signaling network that controls these effector mechanisms during osmotic stress. Our research focuses in particular on the stress response network of gill chloride cells and pavement cells because these cell types are in direct contact with the external milieu and they undergo dramatic biochemical and morphological changes in response to osmotic stress and other types of environmental stress.

The overall goal of our studies on fish gill cells is to identify and functionally understand key components of the stress response network to develop predictive models and more robust and predictive biomarkers of environmental stress exposure in fishes. By comparing such networks in several evolutionarily distinct lineages of fishes with those of mammals we aim to get insight into how stress response networks of vertebrates have evolved and how they can be most effectively manipulated for the benefit of animal and human health. Practical implications of our research also include improvement of aquaculture practices (tilapia, sturgeon), conservation efforts aimed at maintaining ecosystem health and protection of endangered species (sturgeon, sharks), and invasive species control (tilapia).