Substances	Interaction	Organism	Category

Substances	Interaction	Organism	Category

     glycogen storage disease type VI At least 17 mutations in the PYGL gene have been found to cause glycogen storage disease type VI (GSDVI). Most mutations change single protein building blocks (amino acids) in liver glycogen phosphorylase, affecting the normal function of the enzyme. In the Old Order Mennonite population, a common mutation (written as 1620+1G>A) disrupts the way the PYGL gene's instructions are used to make the enzyme. A defective liver glycogen phosphorylase enzyme impairs the normal breakdown of glycogen. As a result, liver cells cannot use glycogen for energy, so liver function becomes impaired. A lack of glycogen breakdown within liver cells leads to the major features of GSDVI.

     The PYGL gene provides instructions for making an enzyme called liver glycogen phosphorylase. This enzyme breaks down a complex sugar called glycogen. Liver glycogen phosphorylase is one of three related enzymes that break down glycogen in cells; the other glycogen phosphorylases are found in the brain and in muscles. Liver glycogen phosphorylase is found only in liver cells, where it breaks down glycogen into a type of sugar called glucose-1-phosphate. Additional steps convert glucose-1-phosphate into glucose, a simple sugar that is the main energy source for most cells in the body.

Condition	Change (log2fold)	Comparison	Species	Experimental variables	Experiment name

Condition	Change (log2fold)	Comparison	Species	Experimental variables	Experiment name

The following transcription factors affect gene expression:

• HNF-4alpha1
• HNF-4alpha2
• c-Myc
• GATA-1
• Tal-1beta
• GATA-2
• GATA-3
• E47

Enzyme Regulation:

Activity of phosphorylase is controlled both by allosteric means (through the noncovalent binding of metabolites) and by covalent modification. Thus AMP allosterically activates, whereas ATP, ADP, and glucose-6-phosphate allosterically inhibit, phosphorylase B.

Molecular Function:

• Purine Nucleobase Binding
• Atp Binding
• Glucose Binding
• Drug Binding
• Glycogen Phosphorylase Activity
• Amp Binding
• Vitamin Binding
• Pyridoxal Phosphate Binding
• Bile Acid Binding
• Protein Homodimerization Activity

Biological Processes:

• Glycogen Metabolic Process
• Glycogen Catabolic Process
• 5-Phosphoribose 1-Diphosphate Biosynthetic Process
• Glucose Homeostasis
• Necroptotic Process

Drug Bank:

• Adenosine Monophosphate

*synonyms