Fig. 1
From: HK2: a potential regulator of osteoarthritis via glycolytic and non-glycolytic pathways
The pivotal role of HK2 in the glycolytic pathway. HK2 can catalyze the conversion of glucose to glucose-6-phosphate (G-6-P). Subsequently, G-6-P initiated the main pathway of glucose utilization, including glycolysis. There are five isotypes of HK family are founded in mammals: HK1, HK2, HK3, HK4 and HKDC1, the expression levels in various tissues and cells are different. HK1 is ubiquitous in mammalian tissues and has a high content in the brain. HK2 is a major regulated isoform in various types of tissues cell lines, and mainly found to be expressed in musculoskeletal system and heart cells. HK3 was mainly distributed in bone marrow, lung and spleen. HK4 regulates insulin secretion, glucose uptake, glycogen synthesis and decomposition in liver. HKDC1 is widely expressed in the pharynx, thymus, colon, and eyes