Balazova 2014 Abstract MiP2014
|Balanced ratio of anionic mitochondrial phospholipids is important for mitochondrial functions in the yeast Saccharomyces cerevisiae.|
Phosphatidylglycerol (PG) is a metabolic precursor to the anionic mitochondrial phospholipid, cardiolipin (CL). The typical feature of a mutant without CL synthase (crd1) is a lack of CL and accumulation of PG. Deletion of the PGC1 gene encoding PG specific phospholipase C also causes accumulation of PG, especially in inositol-free media . The major difference in phospholipid composition between S. cerevisiae crd1 and pgc1 mutant mitochondria is a lack of CL in the crd1 mutant strain. In the present work we investigate the impact of PG accumulation on mitochondrial functions to better understand how controlling anionic phospholipid levels affects cellular functions.
Our results indicate that accumulation of PG in mitochondria of the pgc1 mutant with normal levels of CL causes growth defects at increased temperature, decreased respiratory control ratio, increase of respiration rates 3- and 4-fold compared to the wild type. These results complement already published data , which suggests that a lack of CL in the crd1 mutant results in defects in cell wall biosynthesis, in reduced survival at increased temperature and in mitochondrial DNA instability. Recently, it was shown that the absence of CL in the crd1 mutant causes reduced respiratory control ratio and destabilization of supercomplexes of the respiratory chain .
Taken together, our results indicate that not only a lack of anionic phospholipids but also the excess of PG or unbalanced ratio of anionic phospholipids in mitochondrial membranes has harmful consequences for mitochondrial functions.
Labels: MiParea: Respiration
Stress:Temperature Organism: Saccharomyces cerevisiae
Event: A1, Poster MiP2014
Dep Biochem of Biomembranes, Inst of Animal Biochem and Genetics, Slovak Acad of Sc, Ivanka pri Dunaji, Slovakia. – Maria.Balazova@savba.sk
References and acknowledgemets
Supported by the Slovak Grant Agency of Science (VEGA 2/0168/14) and the Slovak Research and Development. Agency contracts No. LPP-0291-09 and APVV-0123-10.
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