Régulation de l’expression génique par les acides gras

Abstract

The last decade has provided evidence that major (glucose, fatty acids, amino acids) or minor (iron, vitamins...) dietary constituents regulated gene expression in an hormonal-independent way. This review focuses on molecular mechanisms by which fatty acids control in a positive or negative manner the expression of genes encoding regulatory protein involved in their own metabolism. Non esterified fatty acids or their CoA derivatives seem to be the main metabolite signals involved in the transcriptional effect of long-chain fatty acids. The effects of fatty acids are either direct, owing to their specific binding to various nuclear receptors (PPAR, LXR, HNF-4α) leading to changes in the trans-activating activity of these transcription factors, or indirect, as the result of changes in the abundance of regulatory transcription factors (SREBP-1c, ChREBP...). The relative contribution of each transcription factor in the fatty acid-induced positive or negative regulation of gene expression is discussed.