Phenotypic flexibility in respiratory traits is associated with improved aerial respiration in an amphibious fish out of water.
J Exp Biol
; 222(Pt 2)2019 01 17.
Article
em En
| MEDLINE
| ID: mdl-30446543
ABSTRACT
Amphibious fishes have evolved multiple adaptive strategies for respiring out of water, but there has been less focus on reversible plasticity. We tested the hypothesis that when amphibious fishes leave water, enhanced respiratory performance on land is the result of rapid functional phenotypic flexibility of respiratory traits. We acclimated four isogenic strains of Kryptolebias marmoratus to air for 0, 1, 3 or 7â
days. We compared respiratory performance out of water with traits linked to the O2 cascade. Aerial O2 consumption rate was measured over a step-wise decrease in O2 levels. There were significant differences between strains, but time out of water had the largest impact on measured parameters. Kryptolebiasmarmoratus had improved respiratory performance [lower aerial critical oxygen tension (Pcrit), higher regulation index (RI)] after only 1â
day of air exposure, and these changes were strongly associated with the change in hematocrit and dorsal cutaneous angiogenesis. Additionally, we found that 1 h of air exposure induced the expression of four angiogenesis-associated genes - vegfa, angpt2, pecam-1 and efna1 - in the skin. After 7â
days in air, respiratory traits were not significantly linked to the variation in either aerial Pcrit or RI. Overall, our data indicate that there are two phases involved in the enhancement of aerial respiration an initial rapid response (1â
day) and a delayed response (7â
days). We found evidence for the hypothesis that respiratory performance on land in amphibious fishes is the result of rapid flexibility in both O2 uptake and O2 carrying capacity.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Fenótipo
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Respiração
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Ciprinodontiformes
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Ecossistema
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Características de História de Vida
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Variação Biológica Individual
Tipo de estudo:
Risk_factors_studies
Limite:
Animals
Idioma:
En
Revista:
J Exp Biol
Ano de publicação:
2019
Tipo de documento:
Article