Specific subcellular targeting of PKC[alpha] and PKC[epsi] in normal and tumoral lactotroph cells by PMA-mitogenic stimulus

• Published in: Journal of molecular histology 2009-10, Vol.40 (5-6), p.417
• Main Authors: Petiti, Juan Pablo, Gutiérrez, Silvina, Mukdsi, Jorge Humberto, De Paul, Ana Lucía, Torres, Alicia Inés
• Format: Article
• Language: English
• ISSN: 1567-2379; 1567-2387
• DOI: 10.1007/s10735-010-9255-9

The variations of the intracellular localization of the individual protein kinase C (PKC) isoforms are related with their different biological functions. In this study, we have investigated the precise intracellular translocation of endogenous PKCα and PKCε in PMA-stimulated normal and tumoral lactotroph cells by using confocal and immunogold electron microscopy, which was correlated with the rate of cell proliferation of both pituitary cell phenotypes. The present results showed that the short phorbol ester incubation stimulated the proliferation of normal and tumoral lactotroph cells, as determined by the measurement of the BrdU-labelling index. The translocation of PKCα to plasma and nuclear membranes induced by PMA was more marked than that observed for PKCε in normal and tumoral lactotroph cells. Our results showed that PKCs translocation to the plasma and nuclear membranes varied from isozyme to isozyme emphasizing that PKCα could be related with the mitogenic stimulus exerted by phorbol ester. These data support the notion that specific PKC isozymes may exert spatially defined effects by virtue of their directed translocation to distinct intracellular sites.[PUBLICATION ABSTRACT]