ABSTRACT
This chapter discusses advances of the regulation of the mouse stearoyl-CoA desaturase (SCD) genes by dietary fat, emphasizing the role of polyunsaturated fatty acids. The regulation of SCD by polyunsaturated fatty acids (PUFAs) may occur at several levels. Some evidence has been provided that some PUFAs, such as sterculic acid and thia fatty acids, directly inhibit the SCD activity. PUFA-mediated suppression of SCD1 expression in liver and primary hepatocytes and of SCD2 expression in lymphocytes was shown to be largely due to a decrease in their rates of gene transcription. PUFAs can control the synthesis of monounsaturated fatty acids in liver and other tissues by regulating the expression of the SCD genes. In this way PUFAs can affect the membrane fluidity and the metabolic state of cells. The regulation of the SCD gene may, therefore, be more important than that of other lipogenic genes considering the multitude of human diseases linked to abnormal synthesis of monounsaturated fatty acids.
