Specific characteristics of phosphofructokinase-microtubule interaction.
Muscle phosphofructokinase interacts with microtubule-associated protein-free microtubules resulting in a reduction of the overall activity of the enzyme [Lehotzky et al. (1993) J. Biol. Chem. 268, 10888-10894] and periodical cross-linking of the tubules [Lehotzky et al. (1994) Biochem. Biophys. Res. Commun. 204, 585-591]. Microtubule polymers of 'tail-free' tubulin obtained by removal of the carboxy-termini with limited subtilisin digestion retain the binding domains for phosphofructokinase that cross-bridges microtubule 'bodies'. Microtubule-associated proteins bound on tubulin 'tails' do not perturb the kinase binding. These data suggest that the tubulin carboxy-terminal domain is not involved in microtubule-phosphofructokinase interactions and phosphofructokinase and microtubule-associated proteins have distinct binding domains on microtubules. Of different isoforms of phosphofructokinase, occurring mainly in brain and tumor cells, the muscle isoform exhibits selective adsorption behaviour on microtubules. Phosphofructokinase M and C isoforms with different associative and allosteric properties may represent an auxiliary pathway to modulate energy production via glycolysis.
Vértessy
B G
BG
Institute of Enzymology, Hungarian Academy of Sciences, Budapest, Hungary.
Kovács
J
J
Ovádi
J
J
D000818:Animals; D004591:Electrophoresis, Polyacrylamide Gel; D007527:Isoenzymes / Q000302:isolation & purification / Q000378:metabolism; D007700:Kinetics; D008854:Microscopy, Electron; D008869:Microtubule-Associated Proteins / Q000378:metabolism / Q000648:ultrastructure; D008870:Microtubules / Q000378:metabolism* / Q000648:ultrastructure; D018482:Muscle, Skeletal / Q000201:enzymology*; D010732:Phosphofructokinase-1 / Q000302:isolation & purification / Q000378:metabolism*; D011485:Protein Binding; D011817:Rabbits; D013381:Subtilisins
D007527:Isoenzymes; D008869:Microtubule-Associated Proteins; D010732:Phosphofructokinase-1; D013381:Subtilisins