C-FOSREGULATESAXONBRANCHING IN NEURONS

RODRIGUEZ L,FERRERO GO, CARDOZO GIZZI AM, CAPUTTO BL.

Mendoza

Congreso; XLVIII Reunión Anual de la Sociedad Argentina de Investigación en Bioquímica y Biología Molecular; 2012

It was previously shown in our laboratory that in addition to its nuclear activity, c-Fos associates to membranes of the endoplasmic reticulum (ER) and activates phospholipid synthesis. So, it might be associated with the molecular mechanisms that allow the higher rate of membrane genesis required for neuronal growth and differentiation. Primary cultures of hippocampal neurons were infected using a lentiviral vector that expresses a specific sequence (shRNA) against c-Fos to block its expression and no development of axonal processes was observed after 36 hours of culture. On the other hand, by immunofluoressence, we observed the presence of c- Fos co-localizing with ER markers in the neuronal soma and mainly forming structures in the branching sites of the neuronal processes. Finally, FRET technique has given positive results for the interaction between c-Fos and CTPß2. This is an integral enzyme of the membranes of the ER in neuronal cultures that plays an important role during the formation of axon branches. We also observed co-immunoprecipitation of both proteins. These results support our hypothesis of c-Fos mediated activation of phospholipids synthesis during neuronal differentiation.