Cytosolic phosphofructokinase 1 catalyzes the reaction of fructose 6-phosphate and ATP to form fructose 1,6-bisphosphate and ADP. This reaction, irreversible under physiological conditions, is the rate limiting step of glycolysis. Phosphofructokinase 1 activity is allosterically regulated by ATP, citrate, and fructose 2,6-bisphosphate.
Phosphofructokinase 1 is active as a tetramer (although higher order multimers, not annotated here, may form in vivo). Two isoforms of phosphofructokinase 1 monomer, L and M, are widely expressed in human tissues. Different tissues can contain different homotetramers or heterotetramers: L4 in liver, M4 in muscle, and all possible heterotetramers, L4, L3M, L2M2, LM3, and M4, in red blood cells, for example (Raben et al. 1995; Vora et al. 1980, 1987; Vora 1981). A third isoform, P, is abundant in platelets, where it is found in P4, P3L, P2L2, and PL3 tetramers (Eto et al. 1994; Vora et al. 1987).
|PFK tetramer||6-phosphofructokinase activity (0003872)|
|8117307||Cloning of a complete protein-coding sequence of human platelet-type phosphofructokinase isozyme from pancreatic islet.||Biochem Biophys Res Commun||1994|
|7825568||Functional expression of human mutant phosphofructokinase in yeast: genetic defects in French Canadian and Swiss patients with phosphofructokinase deficiency||Am J Hum Genet||1995|
|6451249||Isozymes of human phosphofructokinase in blood cells and cultured cell lines: molecular and genetic evidence for a trigenic system||Blood||1981|
|6444721||Isozymes of human phosphofructokinase: identification and subunit structural characterization of a new system||Proc Natl Acad Sci U S A||1980|
|2960695||Characterization of the enzymatic defect in late-onset muscle phosphofructokinase deficiency. New subtype of glycogen storage disease type VII.||J Clin Invest||1987|