PT  - JOURNAL ARTICLE
AU  - Tiku, P. E.
AU  - Gracey, A. Y.
AU  - Macartney, A. I.
AU  - Beynon, R. J.
AU  - Cossins, A. R.
TI  - Cold-Induced Expression of Δ<sup>9</sup>-Desaturase in Carp by Transcriptional and Posttranslational Mechanisms
AID  - 10.1126/science.271.5250.815
DP  - 1996 Feb 09
TA  - Science
PG  - 815--818
VI  - 271
IP  - 5250
4099  - http://science.sciencemag.org/content/271/5250/815.short
4100  - http://science.sciencemag.org/content/271/5250/815.full
SO  - Science1996 Feb 09; 271
AB  - Poikilothermic animals respond to chronic cold by increasing phosphoglyceride unsaturation to restore the fluidity of cold-rigidified membranes. Despite the importance of this compensatory response, the enzymes involved have not been clearly identified, and the mechanisms that control their activity are unknown. In carp liver, cold induces an 8- to 10-fold increase in specific activity of the microsomal stearoyl coenzyme A desaturase. Cold-induced up-regulation of gene transcription resulted in a 10-fold increase in desaturase transcript amounts after 48 to 60 hours. However, this increase was preceded by the activation of latent desaturase, probably by a posttranslational mechanism. These two mechanisms may act sequentially to match desaturase expression to the demands imposed by a progressive decrease in temperature.