Calcium/calmodulin-dependent protein kinase II: role in learning and memory

Numerous studies over the past decade have established a role(s) for protein phosphorylation in modulation of synaptic efficiency. This article reviews this data and focuses on putative functions of Ca²⁺/calmodulin-dependent protein kinase II (CaM-kinase II) which is highly concentrated at these synapses which utilize glutamate as the neurotransmitter. Evidence is presented that CaM-kinase II can phosphorylate these glutamate receptor/ion channels and enhance the ion current flowing through them. This may contribute to mechanisms of synaptic plasticity that are important in cellular paradigms of learning and memory such as long-term potentiation in the hippocampus.