Levels and activity of brain protein kinase C α and ζ during the aging of the medfly

Brain protein kinase C (PKC) activity, as well as PKCα and PKCζ levels detected by immunoblotting, were monitored during the lifespan of the Mediterranean fruit-fly Ceratitis capitata. PKC activity increased in the particulate fraction during the last stages of the life of C. capitata. Immunoblotting studies with an anti-PKCα antibody also demonstrated increased enzyme levels in the particulate fraction. Cytosolic levels of PKCζ decreased in the terminal phase of the lifespan of the fly, whereas levels of membrane-bound PKCζ increased at that stage. Results thus indicate that during C. capitata final phase of life a translocation of PKCα and PKCζ to the particulate fraction occurs, and therefore both kinases could be involved in the terminal process of this fruit-fly.