Glykogeninproteiini

Glykogeninproteiini, often referred to simply as glycogenin, is a crucial protein involved in the synthesis of glycogen, the primary storage form of glucose in animals. It acts as a primer for glycogen synthesis, meaning it provides a starting point for the addition of glucose units. Glycogenin is a homodimer, composed of two identical subunits, each of which can attach glucose residues to itself. This self-glycosylation is the initial step in glycogen formation. Once a short chain of glucose molecules is attached to glycogenin, other enzymes, specifically glycogen synthase, can then take over and elongate the glycogen chain further. Glycogenin is found in the liver and muscles, where glycogen storage is essential for energy regulation. Its enzymatic activity is regulated, ensuring that glycogen synthesis occurs when glucose levels are high and is inhibited when they are low. Mutations or deficiencies in glycogenin can lead to glycogen storage diseases, highlighting its critical role in metabolic health.