Cold-Induced Accumulation Of Omega-3 Polyunsaturated Fatty Acid In A Liverwort, Marchantia Polymorpha L.

The liverwort Marchantia polymorpha L. synthesizes various long-chain polyunsaturated fatty acids including arachidonic acid and eicosapentaenoic acid, neither of which is produced by higher plants. Here we report the effects of temperature on long-chain polyunsaturated fatty acid accumulation in the liverwort. The accumulation of omega-3 polyunsaturated fatty acids increased significantly as the growth temperature decreased. Specifically, the relative content of eicosapentaenoic acid to total fatty acids at 5 degrees C was approximately 3-fold higher than at 25 degrees C. On the other hand, the accumulation of omega-6 polyunsaturated fatty acids decreased at low temperatures. An analysis of gene expression indicated that the mRNA of the MpFAD3 gene for ER omega-3 desaturase increased significantly at 5 degrees C. These results indicate that in the liverwort the n-3 pathway was enhanced at low temperature, mainly via expression of the cold-induced omega-3 desaturase gene, leading to increased accumulation of eicosapentaenoic acid.