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Genetic engineering of AtAOX1a in Saccharomyces cerevisiae prevents oxidative damage and maintains redox homeostasis.

ABSTRACT: This study aimed to validate the physiological importance of Arabidopsis thaliana alternative oxidase 1a (AtAOX1a) in alleviating oxidative stress using Saccharomyces cerevisiae as a model organism. The AOX1a transformant (pYES2AtAOX1a) showed cyanide resistant and salicylhydroxamic acid (SHAM)-sensitive respiration, indicating functional expression of AtAOX1a in S. cerevisiae. After exposure to oxidative stress, pYES2AtAOX1a showed better survival and a decrease in reactive oxygen species (ROS) when compared to S. cerevisiae with empty vector (pYES2). Furthermore, pYES2AtAOX1a sustained growth by regulating GPX2 and/or TSA2, and cellular NAD (+)/NADH ratio. Thus, the expression of AtAOX1a in S. cerevisiae enhances its respiratory tolerance which, in turn, maintains cellular redox homeostasis and protects from oxidative damage.

SUBMITTER: Vishwakarma A

PROVIDER: S-EPMC4821348 | biostudies-literature | 2016 Feb

REPOSITORIES: biostudies-literature

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Genetic engineering of AtAOX1a in Saccharomyces cerevisiae prevents oxidative damage and maintains redox homeostasis.

Vishwakarma Abhaypratap A Dalal Ahan A Tetali Sarada Devi SD Kirti Pulugurtha Bharadwaja PB Padmasree Kollipara K

FEBS open bio 20160201 2

This study aimed to validate the physiological importance of Arabidopsis thaliana alternative oxidase 1a (AtAOX1a) in alleviating oxidative stress using Saccharomyces cerevisiae as a model organism. The AOX1a transformant (pYES2AtAOX1a) showed cyanide resistant and salicylhydroxamic acid (SHAM)-sensitive respiration, indicating functional expression of AtAOX1a in S. cerevisiae. After exposure to oxidative stress, pYES2AtAOX1a showed better survival and a decrease in reactive oxygen species (ROS) ...[more]

PMID: 27239435

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