A Polar Dinoflagellate that Can Really Take the Heat
Zheng, S., Wang, G. and Lin, S. 2012. Heat shock effects and population survival in the polar dinoflagellate Polarella glacialis. Journal of Experimental Marine Biology and Ecology 438: 100-108.
In an effort to gain further enlightenment about the subject, Zheng et al. studied the effects of temperature shock on the growth of the dinoflagellate Polarella glacialis. This they did "by monitoring its physiological and biochemical responses to temperature rises from 4°C to 10 and 15°C," while examining the growth rate and expression of two important genes for this alga.
The three researchers say "it is noteworthy that in the present study the cultures were directly transferred from 4°C to 10 and 15°C without progressive intermediate steps," and they state that in response to these sudden temperature shifts, "the cultures first experienced a period of declination, then cell density tended to become stable, a sign that a part of the cell population survived."
In light of what they observed, Zheng et al. conclude that "if the species can survive such heat shock in the long term, there is good opportunity that it can be transported from polar regions to temperate or even warmer waters," which perhaps explains, in their words, why "taxa closely related to this species occur in temperate aquatic environments (Lin et al., 2009, 2010)." And if P. glacialis and other related species can do that, coping with projected global warming should be a non-problem.
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