RT info:eu-repo/semantics/article T1 Lipid Droplet Biogenesis Induced by Stress Involves Triacylglycerol Synthesis That Depends on Group VIA Phospholipase A2 A1 Gubern, Albert A1 Barceló-Torns, Miquel A1 Casas, Javier A1 Barneda, David A1 Masgrau, Roser A1 Picatoste, Fernando A1 Balsinde, Jesús A1 Balboa, María A. A1 Claro, Enrique AB This work investigates the metabolic origin of triacylglycerol (TAG) formed during lipid droplet (LD) biogenesis induced by stress. Cytotoxic inhibitors of fatty acid synthase induced TAG synthesis and LD biogenesis in CHO-K1 cells, in the absence of external sources of fatty acids. TAG synthesis was required for LD biogenesis and was sensitive to inhibition and down-regulation of the expression of group VIA phospholipase A(2) (iPLA(2)-VIA). Induction of stress with acidic pH, C(2)-ceramide, tunicamycin, or deprivation of glucose also stimulated TAG synthesis and LD formation in a manner dependent on iPLA(2)-VIA. Overexpression of the enzyme enhanced TAG synthesis from endogenous fatty acids and LD occurrence. During stress, LD biogenesis but not TAG synthesis required phosphorylation and activation of group IVA PLA(2) (cPLA(2)alpha). The results demonstrate that iPLA(2)-VIA provides fatty acids for TAG synthesis while cPLA(2)alpha allows LD biogenesis. LD biogenesis during stress may be a survival strategy, recycling structural phospholipids into energy-generating substrates. SN 0021-9258 YR 2009 FD 2009 LK https://uvadoc.uva.es/handle/10324/64295 UL https://uvadoc.uva.es/handle/10324/64295 LA eng NO The Journal of biological chemistry 284, 5697–5708 (2009). NO Producción Científica DS UVaDOC RD 12-sep-2024