Abstract
The present study aimed to find out a link between ageing of rat and lamprey erythrocytes and activity of two isoforms of protein kinase C (PKC), РKСα and РKСζ. The whole cell population was separated into fractions of different ages in Percoll density gradient. The validity of separation was confirmed by the number of immature erythrocytes, reticulocytes. PKC activity was analyzed in cytosolic and membrane cell fractions. Rat erythrocytes express both PKC isoforms, РKСα and РKСζ, whereas lamprey erythrocytes express only РKСζ. РKСα is identified as a major band at ~ 80 kDa and minor bands at ~ 55–65 kDa; РKСζ is represented by a single band at ~ 80 kDa. In young rat erythrocytes, РKСα is detected mainly in cytosolic fractions, while in membrane fractions its level is by far lower. As cells age, PKCα is translocated from the cytosol to membranes and undergoes proteolytic degradation due to repeated cycles of activation. As a result, in aged erythrocytes relative total PKCα expression (as a sum of expressions in the cytosol and membranes per total protein level) diminishes, indicating a depletion of the PKCα pool and a decline in its functional activity. In both animal species, a highest PKCζ level is observed in the cytosol of young erythrocytes. Erythrocyte ageing is accompanied by a gradual decrease in expression of free cytosolic PKCζ and concurrent increase in the level of its membrane-bound forms. However, in contrast to PKCα, PKCζ is not proteolyzed; its total level in cells and perhaps functional activity do not change throughout the erythrocyte lifespan.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Journal of Evolutionary Biochemistry and Physiology
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
