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Not to be confused with Gluconeogenesis or Glycogenolysis.

Glycogenesis is the process of glycogen synthesis, in which glucose molecules are added to chains of glycogen for storage. This process is activated during rest periods following the Cori cycle, in the liver, and also activated by insulin in response to high glucose levels, for example after a carbohydrate-containing meal.


  • Glucose is converted into glucose-6-phosphate by the action of glucokinase or hexokinase.
  • Glucose-6-phosphate is converted into glucose-1-phosphate by the action of phosphoglucomutase, passing through the obligatory intermediate glucose-1,6-bisphosphate.
  • Glucose-1-phosphate is converted into UDP-glucose by the action of the enzyme UDP-glucose phosphorylase. Pyrophosphate is formed, which is later hydrolysed by pyrophosphatase into two phosphate molecules.
  • Glycogenin, a homodimer, has a tyrosine residue on each subunit that serves as the anchor for the reducing end of glycogen. Initially, about eight UDP-glucose molecules are added to each tyrosine residue by glycogenin, forming α(1→4) bonds.
  • Once a chain of eight glucose monomers is formed, glycogen synthase binds to the growing glycogen chain and adds UDP-glucose to the 4-hydroxyl group of the glucosyl residue on the non-reducing end of the glycogen chain, forming more α(1→4) bonds in the process.
  • Branches are made by glycogen branching enzyme (also known as amylo-α(1:4)→α(1:6)transglycosylase), which transfers the end of the chain onto an earlier part via α-1:6 glycosidic bond, forming branches, which further grow by addition of more α-1:4 glycosidic units.

Control and regulations[edit]

Glycogenesis responds to hormonal control.

One of the main forms of control is the varied phosphorylation of glycogen synthase and glycogen phosphorylase. This is regulated by enzymes under the control of hormonal activity, which is in turn regulated by many factors. As such, there are many different possible effectors when compared to allosteric systems of regulation.

Epinephrine (Adrenaline)[edit]

See also: Epinephrine

Glycogen phosphorylase is activated by phosphorylation, whereas glycogen synthase is inhibited.

Glycogen phosphorylase is converted from its less active "b" form to an active "a" form by the enzyme phosphorylase kinase. This latter enzyme is itself activated by protein kinase A and deactivated by phosphoprotein phosphatase-1.

Protein kinase A itself is activated by the hormone adrenaline. Epinephrine binds to a receptor protein that activates adenylate cyclase. The latter enzyme causes the formation of cyclic AMP from ATP; two molecules of cyclic AMP bind to the regulatory subunit of protein kinase A, which activates it allowing the catalytic subunit of protein kinase A to dissociate from the assembly and to phosphorylate other proteins.

Returning to glycogen phosphorylase, the less active "b" form can itself be activated without the conformational change. 5'AMP acts as an allosteric activator, whereas ATP is an inhibitor, as already seen with phosphofructokinase control, helping to change the rate of flux in response to energy demand.

Epinephrine not only activates glycogen phosphorylase but also inhibits glycogen synthase. This amplifies the effect of activating glycogen phosphorylase. This inhibition is achieved by a similar mechanism, as protein kinase A acts to phosphorylate the enzyme, which lowers activity. This is known as co-ordinate reciprocal control. Refer to glycolysis for further information of the regulation of glycogenesis.


See also: Insulin

Insulin has an antagonistic effect to epinephrine signaling via the beta-adrenergic receptor (G-Protein coupled receptor). When insulin binds to its receptor (insulin receptor), it results in the activation (phosphorylation) of Akt which in turn activates Phosphodiesterase (PDE). PDE then will inhibit cyclic AMP (cAMP) action and cause inactivation of PKA which will cause Hormone Sensitive Lipase (HSL) to be dephosphorylated and inactive so that lipolysis and lipogenesis is not occurring simultaneously.

Calcium ions[edit]

Calcium ions or cyclic AMP (cAMP) act as secondary messengers. This is an example of negative control. The calcium ions activate phosphorylase kinase. This activates glycogen phosphorylase and inhibits glycogen synthase.

See also[edit]

External links[edit]

Original courtesy of Wikipedia: http://en.wikipedia.org/wiki/Glycogenesis — Please support Wikipedia.
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25 news items


Thu, 25 Jun 2015 09:14:37 -0700

In their study with rats, the Chinese scientists tried to counter this build-up in the liver by supercharging the gene. "PPP1r3G is a regulatory subunit of protein phosphatase 1 and stimulates glycogenesis in the liver," the study states. "Chronic and ...
The Hindu
Sun, 26 Jul 2015 17:16:05 -0700

Cinnamaldehyde, a potential anti-diabetic agent, had anti-hyperglycemic andanti-hyperlipidemic effects on rodent models of diabetes. Cinnamon can reduce blood glucose via reduction of insulin resistance and increase of hepatic glycogenesis, she said.


Mon, 28 Sep 2015 23:56:15 -0700

Excess blood glucose can be converted and stored as glycogen via a process called glycogenesis - this is so that the body has a constant reserve of energy throughout the day. After all, it is not really practical to snack all day and night, and besides ...

h+ Magazine

h+ Magazine
Thu, 12 Mar 2015 14:12:01 -0700

This established that the mechanism of the treatment of lung tumours with citreoviridin, an inhibitor of ectopic ATP synthase, was due to proteins involved in glycogenesis which increases in lung tumours and whose inhibition reduces their proliferation ...


Mon, 31 Mar 2014 13:22:44 -0700

As the small intestine absorbs glucose, the pancreas releases insulin, which stimulates body tissues and causes them to absorb this glucose and metabolize it (a process known as glycogenesis). This stored glucose (glycogen) is used to maintain healthy ...
Yahoo News
Thu, 10 Apr 2014 10:23:24 -0700

Want peak muscle size along with a boost in strength? You're going to need plenty of carbohydrates. But don't stuff your face with every carb-heavy food in your cabinet. You need to carefully craft your carb consumption. Glycogenesis is the process of ...

WholeFoods Magazine

WholeFoods Magazine
Fri, 18 Jul 2014 17:00:00 -0700

Speaking of the ways phytochemicals can affect metabolic pathways, Bender says, “They affect glucose metabolism (glycolysis, Kreb's cycle), pentose phosphate pathways, glycogenesis, glycogenolysis, gluconeogenesis and absorption of glucose via the ...

BioNews Texas

BioNews Texas
Mon, 07 Apr 2014 05:45:00 -0700

Overactivity of beta cells in the pancreas produce excess insulin (neonatal hyperinsulinism) due to structural, functional, or genetic abnormalities in the glucose-sensing mechanisms in the body. This causes glycogenesis in high rates in hepatic and ...

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