CDS1 (CDP-diacylglycerol synthase 1) catalyzes the conversion of phosphatidic acid to CDP-diacylglycerol, an essential intermediate in phospholipid biosynthesis pathways including phosphatidylglycerol, cardiolipin, and phosphatidylinositol synthesis. The enzyme exhibits no acyl chain preference, accommodating diverse phosphatidic acid substrates with equivalent efficiency. CDS1 plays a critical regulatory role in lipid droplet formation and growth, which are central to cellular lipid and energy homeostasis. Beyond structural roles, CDS1 positively regulates adipocyte differentiation and development, connecting lipid metabolism to cellular lineage specification. The protein localizes to the endoplasmic reticulum and lipid droplet membranes, positioning it strategically for coordinating membrane lipid synthesis with storage organelle biogenesis. CDS1's functions in phosphatidylinositol synthesis link it to signal transduction pathways, given phosphatidylinositol's role as a precursor for second messengers. Dysregulation of CDS1 could impair lipid homeostasis and adipogenesis, with potential relevance to metabolic disorders and obesity. The enzyme represents a key metabolic hub integrating membrane biogenesis, lipid storage, and signaling lipid production essential for cellular and organismal energy metabolism.