Abstract
In the present work we report the presence of protein kinase CK2 in lipid raft preparations from rat brain synaptosomes, obtained after detergent extraction and subsequent isolation of detergent-resistant membranes using sucrose gradient ultracentrifugation. Moreover, the phosphorylation of syntaxin-1 at Ser14, a specific CK2 target, has been detected in lipid rafts, as assessed by a phospho-specific antibody. Treatment with DMAT, a specific CK2 inhibitor, results in a decrease of syntaxin-1 Ser14 phosphorylation in lipid rafts, while the glutamate release from synaptosomes is enhanced. In conclusion, CK2 might control neurotransmitter release by acting on SNARE proteins attached to cholesterol-enriched microdomains.