Physiological functions and regulation of C. elegans Stearoyl-CoA desaturases

Abstract

The nematode Caenorhabditis elegans synthesizes a complex array of unsaturated fatty acids. The stearoyl-CoA desaturases (SCDs), which introduce the first double bond into a saturated fatty acid chain, are encoded by three genes. Two of these genes, fat-6 and fat-7, encode SCDs that introduce a double bond into stearic acid (18:0), generating oleic acid (18:1n-9). The third gene, fat-5, is a palmitoyl-CoA desaturase, which introduces a double bond into palmitic acid (16:0). Powerful molecular and genetic tools in C. elegans, combined with a relatively simple anatomy, make this an ideal model to study the roles and regulation of unsaturated fatty acids. This review summarizes the physiological roles of SCDs in C. elegans that have been determined by the analysis of SCD mutants. Studies examining the regulation of C. elegans SCDs by SREBP, nuclear hormone receptors, and other transcription factors are also highlighted in this chapter.