HK2
Description
The HK2 (hexokinase 2) is a protein-coding gene located on chromosome 2.
HK2, also known as hexokinase 2, is an enzyme encoded by the HK2 gene located on chromosome 2. It is the primary form of hexokinase found in skeletal muscle and is responsible for the initial step of glucose metabolism by phosphorylating glucose to glucose-6-phosphate (G6P). HK2 is located on the outer mitochondrial membrane and its expression is regulated by insulin. Studies in rats suggest that HK2 is involved in the increased glycolysis observed in rapidly growing cancer cells. HK2 is one of four highly similar hexokinase isoforms in mammals. The HK2 gene spans approximately 50 kb and consists of 18 exons. There is also a HK2 pseudogene on the X chromosome, which lacks an open reading frame for gene expression. HK2 is a 100-kDa enzyme composed of 917 amino acids with highly similar N- and C-terminal domains.
HK2 catalyzes the phosphorylation of hexose sugars, like glucose and fructose, to their corresponding 6-phosphate forms. This reaction initiates the glycolytic pathway, converting glucose to glucose-6-phosphate. HK2 also plays a crucial role in maintaining the integrity of the outer mitochondrial membrane by preventing the release of apoptotic factors from the intermembrane space. This action contributes to cell survival and protection against apoptosis.
HK2 is also known as HKII, HXK2.
