Phosphorylation Level of Complex V Proteins of Higher Plant Mitochondria Correlates with Their Redox State
The effect of synthetic cytokinin BAP (6-benzylaminopurine) on protein phosphorylation in the isolated maize mitochondria was investigated. The influence of BAP and classical inhibitors of the mitochondria respiratory complexes, such as rotenone, malonate, SHAM, and KCN, on the level of mitochondrial protein phosphorylation was studied. The activity of the respiratory complexes I and II, assessed by the method of BN-PAGE (blue native polyacrylamide gel electrophoresis), did not differ in mitochondria untreated and treated with BAP. The complex V activity showed a significant decrease in the mitochondrial ATPase activity in mitochondria subjected to the BAP treatment. The effect of BAP was similar to the action of such a specific inhibitor of the membrane-bound mitochondrial ATPase as oligomycin and an inhibitor of protein tyrosine kinases genistein.