Université de Fribourg

Expression of oleosin and perilipins in yeast promote formation of lipid droplets from the endoplasmatic reticulum

Jacquier, Nicolas ; Mishra, Shirish ; Choudhary, Vineet ; Schneiter, Roger

In: Journal of Cell Science, 2013, p. -

Most cells store neutral lipids in a dedicated compartment, the lipid droplet (LD). These LDs are structurally and functionally conserved across species. In higher eukaryotes, LDs are covered by abundant scaffolding proteins, such as the oleosins in plants and perilipins (PLINs) in animal cells. S. cerevisiae, however, has no homologues of these scaffolding proteins. To analyze a possible...

Université de Fribourg

Lipid droplets are functionally connected to the endoplasmic reticulum in Saccharomyces cerevisiae

Jacquier, Nicolas ; Choudhary, Vineet ; Mari, Muriel ; Toulmay, Alexandre ; Health and Human Services, Bethesda, USA ; Reggiori, Fulvio ; Schneiter, Roger

In: Journal of Cell Science, 2011, vol. 124, p. 2424-2437

Cells store metabolic energy in the form of neutral lipids that are deposited within lipid droplets (LDs). In this study, we examine the biogenesis of LDs and the transport of integral membrane proteins from the endoplasmic reticulum (ER) to newly formed LDs. In cells that lack LDs, otherwise LD-localized membrane proteins are homogenously distributed in the ER membrane. Under these conditions,...

Université de Fribourg

Ypk1, the yeast orthologue of the human serum- and glucocorticoid-induced kinase, is required for efficient uptake of fatty acids

Jacquier, Nicolas ; Schneiter, Roger

In: Journal of Cell Science, 2010, vol. 123, p. 2218-2227

Fatty acids constitute an important energy source for various tissues. The mechanisms that mediate and control uptake of free fatty acids from the circulation, however, are poorly understood. Here we show that efficient fatty-acid uptake by yeast cells requires the protein kinase Ypk1, the orthologue of the human serum- and glucocorticoid-induced kinase Sgk1. ypk1δ mutant cells fail to...

Université de Fribourg

The Cdc42 effectors ste20, Cla4, and Skm1 down-regulate the expression of genes involved in sterol uptake by a mitogen-activated protein kinase-independent pathway

Lin, Meng ; Unden, Heike ; Jacquier, Nicolas ; Schneiter, Roger ; Just, Ursula ; Höfken, Thomas

In: Molecular Biology of the Cell, 2009, vol. 20, no. 22, p. 4826-4837

In Saccharomyces cerevisiae, the Rho-type GTPase Cdc42 regulates polarized growth through its effectors, including the p21-activated kinases (PAKs) Ste20, Cla4, and Skm1. Previously, we demonstrated that Ste20 interacts with several proteins involved in sterol synthesis that are crucial for cell polarization. Under anaerobic conditions, sterols cannot be synthesized and need to be imported into...