PFKM

The PFKM gene encodes the muscle isoform of phosphofructokinase (PFK) (ATP:D-fructose-6-phosphate-1-phosphotransferase, EC 2.7.1.11). PFK catalyzes the irreversible conversion of fructose-6-phosphate to fructose-1,6-bisphosphate and is a key regulatory enzyme in glycolysis. Mammalian PFK is a tetramer made up of various combinations of 3 subunits: muscle (PFKM), liver (PFKL; MIM 171860), and platelet (PFKP; MIM 171840), the genes for which are located on chromosomes 12q13, 21q22, and 10p, respectively. The composition of the tetramers differs according to the tissue type. Muscle and liver PFK are a homotetramers of 4M and 4L subunits, respectively. Erythrocytes contain both L and M subunits, which randomly tetramerize to form M4, L4, and M3L, M2L2, and ML3 hybrid forms of the holoenzyme (Vora et al., 1980 [PubMed 6444721]; Raben and Sherman, 1995 [PubMed 7550225]).[supplied by OMIM

Full Name

phosphofructokinase, muscle

Function

Catalyzes the phosphorylation of D-fructose 6-phosphate to fructose 1,6-bisphosphate by ATP, the first committing step of glycolysis.

Biological Process

Canonical glycolysisManual Assertion Based On ExperimentIBA:GO_Central
Fructose 1,6-bisphosphate metabolic processManual Assertion Based On ExperimentIBA:GO_Central
Fructose 6-phosphate metabolic processManual Assertion Based On ExperimentIDA:BHF-UCL
Glucose homeostasisIEA:Ensembl
Glycogen catabolic processIEA:Ensembl
Glycolysis from storage polysaccharide through glucose-1-phosphateIEA:Ensembl
Glycolytic processManual Assertion Based On ExperimentIMP:UniProtKB
Glycolytic process through fructose-6-phosphateManual Assertion Based On ExperimentIMP:CAFA
Muscle cell cellular homeostasisManual Assertion Based On ExperimentIMP:BHF-UCL
Positive regulation of insulin secretionIEA:Ensembl
Positive regulation of transcription by RNA polymerase IIManual Assertion Based On ExperimentIMP:CAFA

Cellular Location

Cytoplasm

Involvement in disease

Glycogen storage disease 7 (GSD7):
A metabolic disorder characterized by exercise intolerance with associated nausea and vomiting, muscle cramping, exertional myopathy and compensated hemolysis. Short bursts of intense activity are particularly difficult. Severe muscle cramps and myoglobinuria develop after vigorous exercise.

PTM

GlcNAcylation decreases enzyme activity.