Lipid droplets (LD) are highly dynamic organelles specialized for the regulation of energy storage and cellular homeostasis. LD consist of a neutral lipid core surrounded by a phospholipid monolayer membrane with embedded proteins, most of which are involved in lipid homeostasis. In this study, we focused on one of the major LD proteins, sterol C24-methyltransferase, encoded by ERG6. We found that the absence of Erg6p resulted in an increased accumulation of yeast perilipin Pet10p in LD, while the disruption of PET10 was accompanied by Erg6p LD over-accumulation. An observed reciprocal enrichment of Erg6p and Pet10p in pet10Δ and erg6Δ mutants in LD, respectively, was related to specific functional changes in the LD and was not due to regulation on the expression level. The involvement of Pet10p in neutral lipid homeostasis was observed in experiments that focused on the dynamics of neutral lipid mobilization as time-dependent changes in the triacylglycerols (TAG) and steryl esters (SE) content. We found that the kinetics of SE hydrolysis was reduced in erg6Δ cells and the mobilization of SE was completely lost in mutants that lacked both Erg6p and Pet10p. In addition, we observed that decreased levels of SE in erg6Δpet10Δ was linked to an overexpression of steryl ester hydrolase Yeh1p. Lipid analysis of erg6Δpet10Δ showed that PET10 deletion altered the composition of ergosterol intermediates which had accumulated in erg6Δ. In conclusion, yeast perilipin Pet10p functionally interacts with Erg6p during the metabolism of ergosterol.
Storage lipids, triacylglycerols (TAG), and steryl esters (SE), are predominant constituents of lipid droplets (LD) in fungi. In several yeast species, metabolism of TAG and SE is linked to various cellular processes, including cell division, sporulation, apoptosis, response to stress, and lipotoxicity. In addition, TAG are an important source for the generation of value-added lipids for industrial and biomedical applications. The fission yeast Schizosaccharomyces pombe is a widely used unicellular eukaryotic model organism. It is a powerful tractable system used to study various aspects of eukaryotic cellular and molecular biology. However, the knowledge of S. pombe neutral lipids metabolism is quite limited. In this review, we summarize and discuss the current knowledge of the homeostasis of storage lipids and of the role of LD in the fission yeast S. pombe with the aim to stimulate research of lipid metabolism and its connection with other essential cellular processes. We also discuss the advantages and disadvantages of fission yeast in lipid biotechnology and recent achievements in the use of S. pombe in the biotechnological production of valuable lipid compounds.
Squalene is a naturally occurring triterpene with wide industrial applications. Due to limited natural resources, production of this valuable lipid in yeast is of high commercial relevance. Typically low levels of squalene in yeast can be significantly increased by specific cultivation conditions or genetic modifications. Under normal conditions, excess squalene is stored in lipid droplets (LD), while in a Saccharomyces cerevisiae mutant unable to form LD it is distributed to cellular membranes. We present here the evidence that squalene accumulation in this LD-less mutant treated with squalene monooxygenase inhibitor terbinafine induces growth defects and loss of viability. We show that plasma membrane malfunction is involved in squalene toxicity. We have found that subinhibitory concentrations of terbinafine increased the sensitivity of LD-less mutant to several membrane-active substances. Furthermore, squalene accumulation in terbinafine-treated LD-less cells disturbed the maintenance of membrane potential and increased plasma membrane permeability to rhodamine 6G. LD-less cells treated with terbinafine showed also high sensitivity to osmotic stress. To confirm the causal relationship between squalene accumulation, loss of viability and impaired plasma membrane functions we treated LD-less cells simultaneously with terbinafine and squalene synthase inhibitor zaragozic acid. Reduction of squalene levels by zaragozic acid improved cell growth and viability and decreased plasma membrane permeability to rhodamine 6G in terbinafine-treated LD-less cells. Our results support the hypothesis that plasma membrane malfunction is involved in the mechanisms of squalene lipotoxicity in yeast cells with defective lipid storage.
Recommendations are given concerning the terminology of methods of bioanalytical chemistry. With respect to dynamic development particularly in the analysis and investigation of biomacromolecules, terms related to bioanalytical samples, enzymatic methods, immunoanalytical methods, methods used in genomics and nucleic acid analysis, proteomics, metabolomics, glycomics, lipidomics, and biomolecules interaction studies are introduced.
Recommendations are given concerning the terminology of methods of bioanalytical chemistry. With respect to dynamic development particularly in the analysis and investigation of biomacromolecules, terms related to bioanalytical samples, enzymatic methods, immunoanalytical methods, methods used in genomics and nucleic acid analysis, proteomics, metabolomics, glycomics, lipidomics, and biomolecules interaction studies are introduced.
Recommendations are given concerning the terminology of methods of bioanalytical chemistry. With respect to dynamic development particularly in the analysis and investigation of biomacromolecules, terms related to bioanalytical samples, enzymatic methods, immunoanalytical methods, methods used in genomics and nucleic acid analysis, proteomics, metabolomics, glycomics, lipidomics, and biomolecules interaction studies are introduced.
Recommendations are given concerning the terminology of methods of bioanalytical chemistry. With respect to dynamic development particularly in the analysis and investigation of biomacromolecules, terms related to bioanalytical samples, enzymatic methods, immunoanalytical methods, methods used in genomics and nucleic acid analysis, proteomics, metabolomics, glycomics, lipidomics, and biomolecules interaction studies are introduced.
Recommendations are given concerning the terminology of methods of bioanalytical chemistry. With respect to dynamic development particularly in the analysis and investigation of biomacromolecules, terms related to bioanalytical samples, enzymatic methods, immunoanalytical methods, methods used in genomics and nucleic acid analysis, proteomics, metabolomics, glycomics, lipidomics, and biomolecules interaction studies are introduced.
Recommendations are given concerning the terminology of methods of bioanalytical chemistry. With respect to dynamic development particularly in the analysis and investigation of biomacromolecules, terms related to bioanalytical samples, enzymatic methods, immunoanalytical methods, methods used in genomics and nucleic acid analysis, proteomics, metabolomics, glycomics, lipidomics, and biomolecules interaction studies are introduced.
Recommendations are given concerning the terminology of methods of bioanalytical chemistry. With respect to dynamic development particularly in the analysis and investigation of biomacromolecules, terms related to bioanalytical samples, enzymatic methods, immunoanalytical methods, methods used in genomics and nucleic acid analysis, proteomics, metabolomics, glycomics, lipidomics, and biomolecules interaction studies are introduced.
Recommendations are given concerning the terminology of methods of bioanalytical chemistry. With respect to dynamic development particularly in the analysis and investigation of biomacromolecules, terms related to bioanalytical samples, enzymatic methods, immunoanalytical methods, methods used in genomics and nucleic acid analysis, proteomics, metabolomics, glycomics, lipidomics, and biomolecules interaction studies are introduced.
Recommendations are given concerning the terminology of methods of bioanalytical chemistry. With respect to dynamic development particularly in the analysis and investigation of biomacromolecules, terms related to bioanalytical samples, enzymatic methods, immunoanalytical methods, methods used in genomics and nucleic acid analysis, proteomics, metabolomics, glycomics, lipidomics, and biomolecules interaction studies are introduced.