CB1 cannabinoid receptor-mediated tyrosine phosphorylation of focal adhesion kinase-related non-kinase.

The effect of cannabinoid on the tyrosine phosphorylation of focal adhesion kinase (FAK) and focal adhesion kinase-related non-kinase (FRNK) was investigated in differentiated mouse neuroblastoma N1E-115 cells. HU-210, a potent cannabinoid agonist, elicited a time-dependent enhancement of tyrosine phosphorylation of FRNK, but not FAK. Pretreatment of cells with antisense oligodeoxynucleotide targeting CB1 cannabinoid receptor abolished HU-210-induced FRNK tyrosine phosphorylation. In addition, pretreatment of cells with 8-Br-cAMP also blocked HU-210-induced FRNK tyrosine phosphorylation. These data demonstrated that HU-210 induces FRNK tyrosine phosphorylation by activating G(i)-coupled CB1 cannabinoid receptor in N1E-115 cells. This newly discovered, cannabinoid-induced FRNK tyrosine phosphorylation might be a novel mechanism for cannabinoid-induced functional changes.