Genetic re-engineering of polyunsaturated phospholipid profile of Saccharomyces cerevisiae identifies a novel role for Cld1 in mitigating the effects of cardiolipin peroxidation

• Published in: Biochimica et biophysica acta. Molecular and cell biology of lipids Vol. 1863; no. 10; pp. 1354 - 1368
• Main Authors: Lou, Wenjia, Ting, Hsiu-Chi, Reynolds, Christian A., Tyurina, Yulia Y., Tyurin, Vladimir A., Li, Yiran, Ji, Jiajia, Yu, Wenxi, Liang, Zhuqing, Stoyanovsky, Detcho A., Anthonymuthu, Tamil S., Frasso, Michael A., Wipf, Peter, Greenberger, Joel S., Bayır, Hülya, Kagan, Valerian E., Greenberg, Miriam L.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01-10-2018
• Subjects: cardiolipin; Cardiolipins - chemistry; Cardiolipins - metabolism; Chromatography, Liquid; Cld1; Fatty Acid Desaturases - genetics; Fatty Acids, Unsaturated - metabolism; Genetic Engineering - methods; Hevea - enzymology; Hevea - genetics; Hydrolysis; Lipid Peroxidation; Mass Spectrometry; mass spectrometry (MS); Oxidative Stress; Phospholipases - metabolism; Plant Proteins - genetics; Plant Proteins - metabolism; polyunsaturated fatty acid (PUFA); remodeling; Saccharomyces cerevisiae - genetics; Saccharomyces cerevisiae - growth & development; Saccharomyces cerevisiae - metabolism; Saccharomyces cerevisiae Proteins - metabolism; yeast; remodeling; Cld1; polyunsaturated fatty acid (PUFA); cardiolipin; lipid peroxidation; yeast; mass spectrometry (MS)
• ISSN: 1388-1981; 1879-2618
• DOI: 10.1016/j.bbalip.2018.06.016

Cardiolipin (CL) is a unique phospholipid localized almost exclusively within the mitochondrial membranes where it is synthesized. Newly synthesized CL undergoes acyl remodeling to produce CL species enriched with unsaturated acyl groups. Cld1 is the only identified CL-specific phospholipase in yeast and is required to initiate the CL remodeling pathway. In higher eukaryotes, peroxidation of CL, yielding CLOX, has been implicated in the cellular signaling events that initiate apoptosis. CLOX can undergo enzymatic hydrolysis, resulting in the release of lipid mediators with signaling properties. Our previous findings suggested that CLD1 expression is upregulated in response to oxidative stress, and that one of the physiological roles of CL remodeling is to remove peroxidized CL. To exploit the powerful yeast model to study functions of CLD1 in CL peroxidation, we expressed the H. brasiliensis Δ12-desaturase gene in yeast, which then synthesized poly unsaturated fatty acids(PUFAs) that are incorporated into CL species. Using LC-MS based redox phospholipidomics, we identified and quantified the molecular species of CL and other phospholipids in cld1Δ vs. WT cells. Loss of CLD1 led to a dramatic decrease in chronological lifespan, mitochondrial membrane potential, and respiratory capacity; it also resulted in increased levels of mono-hydroperoxy-CLs, particularly among the highly unsaturated CL species, including tetralinoleoyl-CL. In addition, purified Cld1 exhibited a higher affinity for CLOX, and treatment of cells with H2O2 increased CLD1 expression in the logarithmic growth phase. These data suggest that CLD1 expression is required to mitigate oxidative stress. The findings from this study contribute to our overall understanding of CL remodeling and its role in mitigating oxidative stress.
•∆12-desaturase expression leads to accumulation of peroxidized cardiolipin.•Cld1 has a higher affinity for peroxidized cardiolipin.•cld1Δ cells expressing Δ12-desaturase exhibit increased peroxidized L4CL.•Δ12-desaturase expression in cld1Δ cells leads to decreased mitochondrial functions.•Δ12-desaturase expression in cld1Δ cells leads to decreased chronological lifespan.