Activation of Fyn kinase by apotransferrin is essential for oligodendrocyte differentiation

MARÍA JULIA PÉREZ; PASQUINI JUANA MARÍA

Los Cocos Cordoba

Simposio; SISTAM 2010, The First South American Spring Symposium in Signal Transduction and Molecular Medicine.; 2010

SISTAM

The Oligodendrocyte (OL) is the cell that produces the myelin membrane around axons in the CNS. Recently, we have observed that apotransferrin (aTf) addition to the culture medium acelerates the differentiation of OL.These effect involves an increase in the expression of the myelin basic protein (MBP). Fyn tyrosine kinase (Fyn) is a member of the Src family of proteins that has been shown to play an important role in myelination. We have recently showed that aTf added to OL primary cultures also activates Fyn at short times (i.e. 15min, 67 ± 3%). Studies were done in order to determine if Fyn is involved in the upregulation of the MBP promoted by aTf ; the increased of MBP expression was abolished by the addition of PP2 (Fyn specific inhibitor) to the culture medium. In order to investigate the molecular mechanisms participating in this effect, we analyzed PI3K y MAPK signalling pathways since recent reports have demonstrated that active Akt increases myelination through the enhancement of OL maturation. Our results show that Akt is activated in the presence of aTf in the culture medium as well as ERK (at 30 min; 273 ± 37 % and 239 ± 140 % respectively). These findings would suggest that aTf effects could be mediated by Fyn and Akt signaling.