Possible pathways involved in activation of catalase and superoxide dismutase with sodium nitroprusside in yeast Saccharomyces cerevisiae.Ukr Biokhim Zh (1999). 2009 Mar-Apr; 81(2):34-9.UB
The effect of nitric oxide (*NO) on biological systems depends very much on many circumstances. Nitric oxide can activate redox sensitive pathways that in many cases results in an increase of antioxidant potential of the cell. However, the direct effects of nitric oxide on the activity of principal antioxidant enzymes such as catalase and superoxide dismutase (SOD) have not been studied. In the present work we exploited the yeast model to elucidate a possibility of regulation of the mentioned activity by NO-donor sodium nitroprusside (SNP). We demonstrated that nitric oxide spontaneously generated at SNP decomposition increased the activity of catalase and SOD 1.3 times. Using inhibitors of mRNA (actinomycin D) and protein (cycloheximide) synthesis, the strain deficient in Yap1p, a master regulator coordinating yeast adaptive response to oxidative stress, we have found that these enzymes are up-regulated via synthesis of new molecules at transcription and translation levels. This response is mediated by Yap1p. Despite the increase of SOD activity in yeast cells possibly includes the activation of the present apoprotein by Ccs1p, the ways of nitric oxide regulation of Ccs1p activity are still unclear.