丙酮酸激酶-M2抗体

PKM

Pyruvate kinase PKM

Monomer and homotetramer. Exists as a monomer in the absence of FBP, and reversibly associates to form a homotetramer in the presence of FBP. The monomeric form binds T3. Tetramer formation induces pyruvate kinase activity. The tetrameric form has high affinity for the substrate and is associated within the glycolytic enzyme complex. Exists in a nearly inactive dimeric form in tumor cells and the dimeric form has less affinity for the substrate. Binding to certain oncoproteins such as HPV-16 E7 oncoprotein can trigger dimerization. FBP stimulates the formation of tetramers from dimers. Interacts with HERC1, POU5F1 and PML. Interacts (isoform M2) with EGLN3; the interaction hydroxylates PKM under hypoxia and enhances binding to HIF1A. Interacts (isoform M2) with HIF1A; the interaction is enhanced by binding of EGLN3, promoting enhanced transcription activity under hypoxia.

Cytoplasm. Nucleus. Note=Translocates to the nucleus in response to different apoptotic stimuli. Nuclear translocation is sufficient to induce cell death that is caspase independent, isoform-specific and independent of its enzymatic activity.

Specifically expressed in proliferating cells, such as embryonic stem cells, embryonic carcinoma cells, as well as cancer cells.

ISGylated.
Under hypoxia, hydroxylated by EGLN3.
Acetylation at Lys-305 is stimulated by high glucose concentration, it decreases enzyme activity and promotes its lysosomal-dependent degradation via chaperone-mediated autophagy.

Belongs to the pyruvate kinase family.

Glycolytic enzyme that catalyzes the transfer of a phosphoryl group from phosphoenolpyruvate (PEP) to ADP, generating ATP. Stimulates POU5F1-mediated transcriptional activation. Plays a general role in caspase independent cell death of tumor cells. The ratio betwween the highly active tetrameric form and nearly inactive dimeric form determines whether glucose carbons are channeled to biosynthetic processes or used for glycolytic ATP production. The transition between the 2 forms contributes to the control of glycolysis and is important for tumor cell proliferation and survival.