About the structure and biological function of TAG
Structure. Triacylglycerols (triglycerides, TAG, or TG) are a type of glycerolipids. Their structure consists of a glycerol backbone linked to three fatty acids. The fatty acids can be of variable length, hydroxylated, and contain double bonds.
Occurrence.Triacylglycerols are found mainly in eukaryotic cells and are elevated in animal adipose tissue as well as fruits and seeds of plants. On a subcellular level, they are enriched in lipid droplets.
Function. Triacylglycerols are a great source of energy in eukaryotes. Commercially important fats and oils of animal and plant origin consist almost exclusively of triacylglycerols. They also serve as pool for structural and bioactive fatty acids. The excessive accumulation of triacylglycerols in adipose tissue and other organs results in obesity and other health problems such as cardiovascular disease, fatty liver, and diabetes.
read more ➔
About the structure and biological function of DAG
Structure. Diacylglycerols (diglycerides, DAG, or DG) are a type of glycerolipids. Their structure consists of a glycerol backbone linked to two fatty acids. The fatty acids can be of variable length, hydroxylated, and contain double bonds.
Diacylglycerols are found in all organisms and each cell type, though at low concentrations. On a subcellular level, they are enriched in biological membranes.
Function. Diacylglycerols have different biological functions, of which many depend on the position of the two fatty acids at the glycerol backbone. Thus, diacylglycerols serve as key intermediates in the synthesis of glycerolipids such as glycerophospholipids and triacylglycerols. They can also function in cellular signaling, and their physical properties influence cell membrane biophysics. They are important immunomodulators. Further, diacylglycerols accumulate in many organs in obesity and can be an important factor in cancer.
read more ➔