Analysis of the effect of L-carnitine supplementation on global expression of Sachharomyces cerevisiae cultures

Microarray analysis of the effect of L-carnitine supplementation on global expression of Sachharomyces cerevisiae cultures in logarithmic growing conditions and after exposure to H2O2 induced oxidative stress.

L-Carnitine plays a well documented role in eukaryotic energy homeostasis by acting as a shuttling molecule for activated acyl residues across intracellular membranes. This activity is supported by carnitine acyl-transferases and transporters, and is referred to as the carnitine shuttle. However, several pleiotropic and often beneficial effects of carnitine in humans have been reported that appear to be unrelated to the shuttling activity, but little conclusive evidence regarding the molecular networks that would be affected by carnitine exist. We have recently demonstrated a protective role of carnitine in oxidative stress in yeast that is independent of the carnitine shuttle. A DNA microarray-based global gene expression analysis identified Cyc3p, a cytochrome c heme lyase, as being important for carnitine's protective impact in oxidative stress conditions. These findings establish a direct genetic link to a carnitine-related phenotype that is independent of the shuttle system. The data suggest that the yeast Saccharomyces cerevisiae should provide a useful model for further elucidation of carnitine's physiological roles.

Yeast cultures was grown to mid-log phase with and without carnitine supplementation to a final concentration of 100 mg/L. A second set was grown to mid log phase, with and without carnitine supplementation and exposed to 0.4 mM H2O2 for 30 min. The experiments were performed using biological duplicate.