[6][7] Together with phosphorylases, the enzyme mobilize glucose reserves from glycogen deposits in the muscles and liver.

Glycogen breakdown is highly regulated in the body, especially in the liver, by various hormones including insulin and glucagon, to maintain a homeostatic balance of blood-glucose levels.

Phosphorylase can only cleave α-1,4-glycosidic bond between adjacent glucose molecules in glycogen but branches also exist as α-1,6 linkages.

In E. coli, Glucose transfer is performed by 4-alpha-glucanotransferase, a 78.5 kDa protein coded for by the gene malQ.

TreX's oligomeric form seems to play a significant role in altering both enzyme shape and function.

Dimerization is thought to stabilize a "flexible loop" located close to the active site.

[19] The human glycogen debranching enzyme (gene: AGL) is a monomer with a molecular weight of 175 kDa.

It has been shown that the two catalytic actions of AGL can function independently of each other, demonstrating that multiple active sites are present.

Mapping the disease-causing mutations onto the GDE structure provided insights into glycogen storage disease type III.

[11] The AGL gene provides instructions for making several different versions, known as isoforms, of the glycogen debranching enzyme.

[7] Studies produced by the department of pediatrics at Duke University suggest that the human AGL gene contains at minimum 2 promotor regions, sites where the transcription of the gene begins, that result in differential expression of isoform, different forms of the same protein, mRNAs in a manner that is specific for different tissues.

[28] These different manifestation produce varied symptoms, which can be nearly indistinguishable from Type I GSD, including hepatomegaly, hypoglycemia in children, short stature, myopathy, and cardiomyopathy.

[30] Type III patients be distinguished by elevated liver enzymes, with normal uric acid and blood lactate levels, differing from other forms of GSD.