Kowaltowski 2014 Abstract MiP2014
|Luévano-Martínez LA, Forni FM, dos Santos VT, Souza-Pinto NC, Kowaltowski AJ (2014) Cardiolipin is a key determinant for mitochondrial DNA stability and segregation.|
Mitochondria play a key role in adapting to stress. Cardiolipin, the main anionic phospholipid in mitochondrial (mt) membranes, is expected to be a determinant in this adaptive mechanism, since it modulates the activity of most membrane proteins.
Here, we used Saccharomyces cerevisiae, subjected to conditions that affect mitochondrial metabolism, as a model to determine the possible role of cardiolipin in stress adaptation. Interestingly, we found that thermal stress promotes an increase in cardiolipin content, modifying both surface charge and the physical state of mt-membranes. These changes have effects on mtDNA segregation and mt-morphology, thus adapting cells to thermal stress. Conversely, since a cardiolipin synthase-null mutant strain is unable to adapt to thermal stress, this effect is cardiolipin-dependent. Interestingly, we found that the loss of cardiolipin specifically affects the segregation of mtDNA to daughter cells, leading to a respiratory deficient phenotype after replication. Furthermore, we provide evidence for a physical interaction between cardiolipin and the mitochondrial nucleoid.
In summary, our results demonstrate that the mitochondrial lipid cardiolipin is a key determinant in the maintenance of mtDNA stability, morphology and segregation.
Funded by: FAPESP, CNPq and NAP-Redoxoma.
• O2k-Network Lab: BR Sao Paulo Kowaltowski AJ
Labels: MiParea: Respiration, mt-Membrane, mtDNA;mt-genetics
Stress:Temperature Organism: Saccharomyces cerevisiae
HRR: Oxygraph-2k Event: A1, Oral MiP2014
Dep Bioquímica, Inst Química, Univ São Paulo, Brazil. - [email protected]sp.br