Metabolism of phosphatidylcholine and its implications for lipid acyl chain composition in Saccharomyces cerevisiae

Abstract

Phosphatidylcholine (PC) is a very abundant membrane lipid in most eukaryotes including the model organism Saccharomyces cerevisiae. Consequently, the molecular species profile of PC, i.e. the ensemble of PC molecules with acyl chains differing in number of carbon atoms and double bonds, is important in determining the physical properties of eukaryotic membranes, and should be tightly regulated. In this review current insights in the contributions of biosynthesis, turnover, and remodeling by acyl chain exchange to the maintenance of PC homeostasis at the level of the molecular species in yeast are summarized. In addition, the phospholipid class-specific changes in membrane acyl chain composition induced by PC depletion are discussed, which identify PC as key player in a novel regulatory mechanism balancing the proportions of bilayer and nonbilayer lipids in yeast.

Molecular characterization of seipin and its mutants: implications for seipin in triacylglycerol synthesis

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Targeting surface voids to counter membrane disorders in lipointoxication-related diseases

“…As a consequence, when a single phospholipid type is considered, its acyl chain composition varies greatly depending on the organelle; the saturation rate of the acyl chains increases progressively along the secretory pathway to reach its maximum at the plasma membrane (Schneiter et al, 1999). The fatty acyl content of a phospholipid molecule contributes to its overall shape, which is defined by the cross-sectional area of the headgroup relative to the cross-sectional area of its acyl chains (de Kroon, 2007). For example, an oleoyl chain (C18:1) occupies a larger volume than a palmitoyl chain (C16:0), because the double bond induces a 'kink' in the middle of the chain (Deguil et al, 2011).…”

Characterization of a new class of blue-fluorescent lipid droplet markers for live-cell imaging in plants

“…Techniques such as genome/transcriptome sequencing of whole organism/specific cell types, generating gene knockout/overexpression lines and developments in mass spectrometry have enabled researchers to extend their knowledge of LD composition, function and remodeling in live cells (de Kroon, 2007). But some of the most important insights have come from the use of new imaging techniques.…”