Overexpression of yeast thioredoxin TRX2 reduces p53-mediated cell death in yeast.
We have previously shown that overexpression of the human tumor suppressor protein P53 causes cell death of the yeast Saccharomyces cerevisiae. P53 overproduction led to transcriptional downregulation of some yeast genes, such as the TRX1/2 thioredoxin system, which plays a key role in cell protection against various oxidative stresses induced by reactive oxygen species (ROS). In the present work, the impact of TRX2 overexpression on apoptosis mediated by p53 overexpression in yeast is investigated. In yeast cells expressing P53 under an inducible promoter together with TRX2 under a strong constitutive promoter, we showed that Tr2p overproduction reduced the apoptotic effect exerted by P53 and increased the viability of the P53-overproducing cells. Furthermore, measurements of ROS amounts by flow cytometry and fluorescence microscopy indicated that the TRX2 protein acted probably through its increased detoxifying activity on the P53-generated ROS. The steady-state level and activity of P53 were not affected by TRX2 overexpression, as shown by western blotting and functional analysis of separated alleles in yeast (FASAY), respectively. The growth inhibitory effect of P53 was partially reversed by the antioxidant N-acetylcysteine. Our data strengthen the idea that overexpression of a single gene (trx2) decreases the p53-mediated cell death by decreasing ROS accumulation.
Laboratory of Molecular Biotechnologie of Eukaryotes, Centre of Biotechnology of Sfax, University of Sfax, Sfax, Tunisia.
Yosra
Y
Kamoun
Research Unit of Molecular Biology Leukemia and Lymphomas, Faculty of Medicine of Sousse, Sousse,, Tunisia.
Imed
I
Mabrouk
Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, CEA, CNRS, Université Paris-Sud, Bat 400, 91405 Orsay Cedex, Orsay,, France.
Agnes
A
Delahodde
Laboratory of Plant Protection and Improvement, Centre of Biotechnology of Sfax, University of Sfax,, Sfax, Tunisia.
Fatma
F
Boukid
Laboratory of Plant Protection and Improvement, Centre of Biotechnology of Sfax, University of Sfax,, Sfax, Tunisia.
Ines
I
Yacoubi-Hadj Amor
Laboratory of Molecular Biotechnologie of Eukaryotes, Centre of Biotechnology of Sfax, University of Sfax, Sfax, Tunisia.
Raja
R
Mokdad-Gargouri
Laboratory of Molecular Biotechnologie of Eukaryotes, Centre of Biotechnology of Sfax, University of Sfax, Sfax, Tunisia. faouzi.gargouri@cbs.rnrt.tn.
Ali
A
Gargouri
D017209:Apoptosis; D005434:Flow Cytometry; D015870:Gene Expression; D006801:Humans; D050296:Microbial Viability; D008856:Microscopy, Fluorescence; D017382:Reactive Oxygen Species / Q000032:analysis; D011994:Recombinant Proteins / Q000235:genetics / Q000633:toxicity; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000502:physiology*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics* / Q000378:metabolism*; D013879:Thioredoxins / Q000235:genetics* / Q000378:metabolism*; D016159:Tumor Suppressor Protein p53 / Q000235:genetics* / Q000633:toxicity*
D017382:Reactive Oxygen Species; D011994:Recombinant Proteins; D029701:Saccharomyces cerevisiae Proteins; C516110:TRX2 protein, S cerevisiae; D016159:Tumor Suppressor Protein p53; D013879:Thioredoxins
Cell death; P53; ROS; Yeast; trx2