Application of a YHB1-GFP reporter to detect nitrosative stress in yeast.
Yeast flavohemoglobin (Yhb1p) plays a pivotal role in NO(*) detoxification and has also been implicated in oxidative/reductive stress responses. In this study, we have used a YHB1-GFP reporter expressing a full-length chromosome-tagged Yhb1-GFP fusion protein to monitor changes in flavohemoglobin levels after cell treatment with oxidants, antioxidants and nitric oxide donors. Only nitric oxide donors were found to induce a dose-dependent increase in Yhb1-GFP expression while hydrogen peroxide, menadione and diamide caused a moderate diminution of YHB1-GFP fluorescence. Additionally, the levels of endogenous and hydroperoxide-induced ROS production in the Deltayhb1 mutant were comparable to those in the isogenic wild-type strain. Although peroxides increased NO(*) generation while nitrite and nitric oxide donors augmented ROS levels in yeast cells, their effects were generally not more pronounced in Deltayhb1 than in wild-type cells. Taken together, these data suggest that yeast flavohemoglobin does not contribute to cross-protection against oxidative and nitrosative stress.
Lewinska
Anna
A
Department of Biochemistry and Cell Biology, University of Rzeszow, Rzeszow, Poland. alewinska@o2.pl
Grzelak
Agnieszka
A
Bartosz
Grzegorz
G
D003958:Diamide / Q000494:pharmacology; D049308:Dioxygenases; D005434:Flow Cytometry; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism*; D006420:Hemeproteins / Q000235:genetics / Q000378:metabolism*; D006861:Hydrogen Peroxide / Q000494:pharmacology; D009154:Mutation; D009569:Nitric Oxide / Q000378:metabolism; D020030:Nitric Oxide Donors / Q000494:pharmacology; D018384:Oxidative Stress / Q000187:drug effects; D017382:Reactive Oxygen Species / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism*; D013997:Time Factors; D024483:Vitamin K 3 / Q000494:pharmacology
D006420:Hemeproteins; D020030:Nitric Oxide Donors; D017382:Reactive Oxygen Species; D011993:Recombinant Fusion Proteins; D029701:Saccharomyces cerevisiae Proteins; D003958:Diamide; D049452:Green Fluorescent Proteins; D009569:Nitric Oxide; D024483:Vitamin K 3; D006861:Hydrogen Peroxide; D049308:Dioxygenases; C101796:YHB1 protein, S cerevisiae