The source of the autophagic membrane and the regulation of autophagosome biogenesis are still elusive open issues in the field of autophagy. In our recent study of the role of lipid droplets (LDs) and their constituents in autophagy, we provided evidence that both the biogenesis of LDs and its lipolysis by specific lipases are important for autophagosome biogenesis. Our study sheds new light on the source of the autophagic membrane and suggests that a flow of membranes from the endoplasmic reticulum (ER) to LDs, and from LDs to the ER, is essential for autophagosome biogenesis.
Keywords: Atg8; Ayr1; FAS; Ice2; Ldb16; Ldh1; Yeh1; autophagosome biogenesis; autophagy; fatty acids; lipid droplets; steryl ester; triacylglycerols.