Diacylglycerol (DG or DAG) is a molecule composed of two fatty acid chains (also known as acyl chains) covalently attached to a glycerol backbone. It is a key intermediate in lipid metabolism and plays several important roles in cellular processes, making it significant for various biological functions. One of the most well-known roles of DAG is as a second messenger in cell signaling pathways. DAG is involved in the activation of protein kinase C (PKC), a family of enzymes that regulate a wide range of cellular functions, including cell growth, differentiation, and apoptosis. When cellular signals stimulate the generation of DAG, it activates PKC, which, in turn, phosphorylates specific target proteins. DAG can also have intracellular signaling roles beyond PKC activation. It can influence ion channel activity, cytoskeletal rearrangements, and vesicle trafficking, impacting various cellular processes and functions. DAG is an important precursor in the synthesis of phospholipids, which are essential components of cell membranes. DAG can be further modified by enzymes to form various phospholipids, such as phosphatidylcholine and phosphatidylethanolamine, which are critical for maintaining the structural integrity of cell membranes. DAG is an intermediate in the biosynthesis of triacylglycerols, also known as triglycerides. Triacylglycerols are the primary storage form of fatty acids in adipose tissue and are used for energy storage. DAG is one of the key components in the assembly of triacylglycerols, where it combines with a third fatty acid chain to form TAG. Changes in DAG levels can influence lipid metabolism and insulin sensitivity. Elevated levels of DAG, particularly in certain tissues like muscle and liver, have been associated with insulin resistance and metabolic disorders.

Diacylglycerol (DG) pathway References