Adapting to the Cold

Sci. Signal.  21 Feb 2012:
Vol. 5, Issue 212, pp. ec56
DOI: 10.1126/scisignal.2002968

The gating of potassium channels is temperature sensitive, suggesting that these channels must adapt to function efficiently in the extreme cold. Garrett and Rosenthal (see the Perspective by Öhman) show that the coding sequences for delayed rectifier potassium channels from an Antarctic and a tropical octopus differed at only four positions and gave functionally identical channels when expressed in Xenopus oocytes. A variation in temperature responses instead came from extensive mRNA editing. In particular, an edit that recoded an isoleucine to a valine in the pore of the Antarctic octopus channel greatly accelerated gating kinetics.

S. Garrett, J. J. C. Rosenthal, RNA editing underlies temperature adaptation in K+ channels from polar octopuses. Science 335, 848–851 (2012). [Abstract] [Full Text]

M. Öhman, A cold editor makes the adaptation. Science 335, 805–806 (2012). [Abstract] [Full Text]