Brain-derived neurotrophic factor increases Ca2+/calmodulin-dependent protein kinase 2 activity in hippocampus

Area of Science:

• Neuroscience
• Molecular Biology
• Biochemistry

Background:

• Brain-derived neurotrophic factor (BDNF) plays a crucial role in neuronal plasticity and survival.
• Ca2+/calmodulin-dependent protein kinase 2 (CaMK2) is a key enzyme involved in synaptic plasticity and memory formation.

Purpose of the Study:

• To investigate the effect of BDNF on CaMK2 phosphorylation and activity in rat hippocampal slices.
• To elucidate the signaling pathways mediating BDNF-induced CaMK2 activation.

Main Methods:

• Treatment of rat hippocampal slices with BDNF.
• Immunoblotting to detect CaMK2 subunits.
• Treatment with alkaline phosphatase and protein phosphatase 1.
• Inhibition of phospholipase C and chelation of intracellular calcium.

Main Results:

• BDNF stimulates both phosphorylation and kinase activity of CaMK2.
• BDNF action did not alter the total amount of CaMK2 alpha- and beta-subunits.
• Phosphatase treatments reversed BDNF-induced CaMK2 phosphorylation and activation.
• Inhibition of phospholipase C and intracellular calcium chelation abolished BDNF's effect on CaMK2.

Conclusions:

• BDNF enhances the conversion of CaMK2 to its active, autophosphorylated form.
• BDNF-induced CaMK2 activation is mediated by phospholipase C and intracellular calcium mobilization.
• BDNF affects CaMK2 activity, not its concentration.