Phospholipase D activity is connected with the synaptogenesis and neurite outgrowth of the neuronal stem cells

초록

Phospholipase D (PLD) is a ubiquitous enzyme and believed to be involved in lipid mediated signal transduction and membrane formation. With the idea of PLD plays a role in neurite outgrowth and synaptogenesis of the stem cells, we chased the change of PLD activity during the synaptogenesis of rat brain neuronal stem cells. Neuronal stem cells were extracted from the fetal rat brain at 12 days of gestation and cultured in N2 media with bFGF. Synaptogenesis was induced by removing of bFGF from the media. Neurite outgrowth and PLD activity were monitored simultaneously within 1 to 5 days from induction of the synaptogenesis. Neurite outgrowth was identified by immunostaining of the cultured cells with Tuj1 and PLD activity was checked by conventional method. Neurite outgrowth was increased after removal of bFGF, and PLD activity was increased according to the neurite outgrowth. PLD1 and Synapsin I expression level was checked by immunoprecipitation and Western blotting. Synapsin I expression was increased as increase of neurite outgrowth and PLD activity. PMA treatment increased both synapsin I expression and neurite outgrowth. With the data found, we could conclude PLD is involved in neurite outgrowth and synaptogenesis of the rat brain neuronal stem cells.