Severin 2013 Abstract MiP2013
Severin F, Litvinchuk A, Sokolov S, Rogov A, Markova O, Knorre D (2013) Mitochondrially-encoded protein Var1 promotes loss of respiratory function in Saccharomyces cerevisiae under stressful conditions. Mitochondr Physiol Network 18.08. |
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MiP2013, Book of Abstracts Open Access
Severin F, Litvinchuk A, Sokolov S, Rogov A, Markova O, Knorre D (2013)
Event: MiPNet18.08_MiP2013
The yeast Saccharomyces cerevisiae cells easily lose their mtDNA, especially when under stress. After the loss, the cells acquire resistances to a variety of harsh conditions. This suggests that the loss of mtDNA is driven by an active process. To test this we measured the frequency of petite transformation under stresses (ethidium bromide treatment and heat-shock) and found that an inhibitor of mitochondrial translation erythromycin reduces the frequency of the petite transformation. Apparently, the simplest explanation is that under the stresses some mitochondrially-encoded protein(s) induces further damage of mtDNA. Most of the proteins encoded by mtDNA are membrane-associated, strongly hydrophobic and thus unlikely to interact with DNA. On the contrary, Var1, a component of mitochondrial ribosomes, is hydrophilic, positively charged and prone to aggregation. It appeared that in cells expressing Var1 construct in the nucleus erythromycin had no effect on the frequency of the stress-induced petite transformation. We also found that the addition of DNAse altered Var1 content in the preparation of mitochondrial nucleoids, which is indicative of binding. Importantly, Var1 is conserved only in yeast. Together, it suggests that Var1 physically interacts with mtDNA and under stress negatively regulates its maintenance [1].
Labels: MiParea: mtDNA;mt-genetics, Genetic knockout;overexpression Pathology: Aging;senescence
Organism: Saccharomyces cerevisiae, Fungi
Preparation: Intact organism, Intact cells, Homogenate
Regulation: Temperature
MiP2013
Affiliations and author contributions
1 - Faculty of Bioengineering and Bioinformatics, Moscow State University, Russia;
2 - Belozersky Institute of Physico-Chemical Biology, Moscow State University, Russia;
3 - Institute of Mitoengineering, Moscow State University, Russia; 4Bach Institute of Biochemistry, Russian Academy of Sciences, Moscow, Russia.
Email: [email protected]
References
- Litvinchuk AV, Sokolov SS, Rogov AG, Markova OV, Knorre DA, Severin FF (2013) Mitochondrially-encoded protein Var1 promotes loss of respiratory function in Saccharomyces cerevisiae under stressful conditions. Eur J Cell Biol 92:169-74.