HK3

HK3 or Hexokinase 3 is an enzyme that catalyzes the phosphorylation of six-carbon sugars. It is one of four mammalian hexokinases and is critical in the first step of glucose metabolism, which is the conversion of glucose to glucose-6-phosphate.

Function

File:HK3.png

HK3 enzyme structure

HK3 is encoded by the HK3 gene in humans. It is an allosteric enzyme, meaning its activity is regulated by the binding of a small molecule at a site other than the active site. HK3 has a lower affinity for glucose than the other hexokinases and is inhibited by its product, glucose-6-phosphate.

Clinical significance

Alterations in HK3 have been implicated in several diseases. Overexpression of HK3 has been observed in cancer cells, contributing to the Warburg effect, a phenomenon where cancer cells preferentially use glycolysis for energy production. In diabetes, HK3 plays a role in insulin secretion by pancreatic beta cells.

See also

• Hexokinase
• Glucose metabolism
• Warburg effect
• Diabetes