Article

Genetic Regulation of Unsaturated Fatty Acid Composition in C. elegans

Institute of Biological Chemistry, Washington State University, Pullman, Washington, USA.
PLoS Genetics (Impact Factor: 8.17). 08/2006; 2(7):e108. DOI: 10.1371/journal.pgen.0020108
Source: PubMed

ABSTRACT Synopsis
The ratio of saturated to unsaturated fatty acids has a profound affect on the fluidity and function of cellular membranes. Animals, plants, and microorganisms regulate the synthesis of unsaturated fatty acids during changing environmental conditions, as well as in response to dietary nutrients. In this paper the authors use a combination of genetic and biochemical approaches to address the regulation of unsaturated fatty acid synthesis in the roundworm Caenorhabditis elegans. They identify a new transcription factor, NHR-80, that activates the expression of genes encoding delta-9 fatty acid desaturases, the enzymes responsible for catalyzing the insertion of double bonds into saturated fatty acid chains. These unsaturated fatty acids are critical components of membranes, as well as fat storage molecules. Experiments presented here demonstrate that the worms require adequate synthesis of unsaturated fatty acids for survival and that they maintain intricate regulation of the three delta-9 desaturase genes in response to different nutrients. Abnormalities in lipid metabolism lead to obesity and diabetes in humans; this study contributes to our understanding of the regulation of this metabolic pathway.

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