Thermal limit for metazoan life in question: In vivo heat tolerance of the Pompeii worm
Ravaux, J.; Hamel, G.; Zbinden, M.; Tasiemski, A.A.; Boutet, I.; Léger, N.; Tanguy, A.; Jollivet, D.; Shillito, B. (2013). Thermal limit for metazoan life in question: In vivo heat tolerance of the Pompeii worm. PLoS One 8(5): 6 pp. http://dx.doi.org/10.1371/journal.pone.0064074
In: PLoS One. Public Library of Science: San Francisco. ISSN 1932-6203; e-ISSN 1932-6203, more
| |
Authors | | Top |
- Ravaux, J.
- Hamel, G.
- Zbinden, M.
|
- Tasiemski, A.A.
- Boutet, I.
- Léger, N.
|
- Tanguy, A.
- Jollivet, D.
- Shillito, B.
|
Abstract |
The thermal limit for metazoan life, expected to be around 50°C, has been debated since the discovery of the Pompeii worm Alvinella pompejana, which colonizes black smoker chimney walls at deep-sea vents. While indirect evidence predicts body temperatures lower than 50°C, repeated in situ temperature measurements depict an animal thriving at temperatures of 60°C and more. This controversy was to remain as long as this species escaped in vivo investigations, due to irremediable mortalities upon non-isobaric sampling. Here we report from the first heat-exposure experiments with live A. pompejana, following isobaric sampling and subsequent transfer in a laboratory pressurized aquarium. A prolonged (2 hours) exposure in the 50–55°C range was lethal, inducing severe tissue damages, cell mortalities and triggering a heat stress response, therefore showing that Alvinella’s upper thermal limit clearly is below 55°C. A comparison with hsp70 stress gene expressions of individuals analysed directly after sampling in situ confirms that Alvinella pompejana does not experience long-term exposures to temperature above 50°C in its natural environment. The thermal optimum is nevertheless beyond 42°C, which confirms that the Pompeii worm ranks among the most thermotolerant metazoans. |
|