Trienoic fatty acids and plant tolerance of high temperature

The chloroplast membrane of higher plants contains an unusually high concen tration of trienoic fatty acids. Plants grown in colder temperatures have a higher content of trienoic fatty acids. Transgenic tobacco plants in which the gene encoding chloroplast omega-3 fatty acid desaturase, which synthes izes trienoic fatty acids, was silenced contained a lower level of trienoic fatty acids than wild-type plants and were better able to acclimate to hig her temperatures.