Environmental Physiology Lab

Ammonia excretion

All animals generate ammonia from the catabolism of proteins and amino acids. In fish, ammonia is excreted by diffusion across the gills. 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. Rh proteins transport NH3 and are often associated with other transporters (e.g. Na+/HCO3- exchanger, V-type H+ ATPase, carbonic anhydrase, Na+/HCO3- cotransporter). We are interested in how amphibious fishes continue to excrete or detoxify ammonia when they are out of water. 

We have recently shown that six species of Aplocheiloid killifishes express Rh proteins in their skin and release gaseous NH3 across the skin when out of water (Livingston et al. 2018 PRS-B). Are these traits retained from larval fish? PhD student, Louise Tunnah will continue this work.

More Research in the Wright Lab