Biology

Hypoxia-seeking behavior, metabolic depression and skeletal muscle function in an amphibious fish out of water [RESEARCH ARTICLE]



Giulia S. Rossi and Patricia A. Wright

Several animals enter a state of dormancy to survive harsh environmental conditions. During dormancy, metabolic depression can be critical for economizing on limited endogenous energy reserves. We used two isogenic strains (strain 1 and strain 2) of a self-fertilizing amphibious fish (Kryptolebias marmoratus) to test the hypothesis that animals seek hypoxic microhabitats that, in turn, accentuate metabolic depression during dormancy. Using custom-built tunnels that maintained a longitudinal O2 gradient (hypoxic to normoxic), we assessed the O2 preference of K. marmoratus during prolonged air exposure. In support of our hypothesis, we found that one isogenic strain (strain 2) spent more time in hypoxia compared with normoxia after 21 days in air. Prolonged air exposure in both strains resulted in lower O2 consumption rates compared with active fish (35% depression), which was accentuated (51% depression) when fish were exposed to aerial hypoxia acutely. We then tested the hypothesis that chronic aerial hypoxia acclimation would protect endogenous energy reserves and skeletal muscle integrity, thereby maintaining locomotor performance, possibly owing to hypoxic hypometabolism. We found that air-acclimated fish from both strains were in poorer body condition relative to fish acclimated to aerial hypoxia. Furthermore, aerial hypoxia acclimation minimized glycogen usage (strain 1), lipid catabolism (strain 2) and white muscle atrophy (strain 2), as well as preserved terrestrial locomotor performance compared with fish in air (strain 2). Overall, our findings suggest that some K. marmoratus strains seek microhabitats that accentuate metabolic depression during dormancy, and that microhabitat O2 availability may have significant implications for energy metabolism, and the structure and function of skeletal muscle. Furthermore, the differential responses between isogenic strains suggests that genetic factors also contribute to phenotypic differences in the emersion behavior and physiology of this species.

Source link

Related posts

The people behind the papers – Ximena Anleu Gil & Dominique Bergmann

Newsemia

Peptides encoded by noncoding genes: challenges and perspectives

Newsemia

Dual Recognition of H3K4me3 and DNA by the ISWI Component ARID5 Regulates the Floral Transition in Arabidopsis

Newsemia

This website uses cookies to improve your experience. We'll assume you're ok with this, but you can opt-out if you wish. Accept Read More

Privacy & Cookies Policy

COVID-19

COVID-19 (Coronavirus) is a new illness that is having a major effect on all businesses globally LIVE COVID-19 STATISTICS FOR World