Substrate-selective and Calcium-independent Activation of CaMKII by α-Actinin

Abstract

Background: Synaptic signaling is modulated by protein-protein interactions involving receptor ion channels, cytoskeletal proteins, and protein kinases. Results: ␣-Actinin enhances CaMKII signaling to GluN2B-NMDARs, but interferes with CaMKII signaling to GluA1-AMPARs. Conclusion: CaMKII actions on key synaptic targets can be differentially modulated by a Ca 2ϩ -independent interaction with ␣-actinin. Significance: These findings provide new molecular insights into the synaptic mechanisms underlying learning and memory.

Enzymatic Activity of CaMKII Is Not Required for Its Interaction with the Glutamate Receptor Subunit GluN2B

“…Here, we show that neither synaptic translocation nor CaMKII/GluN2B binding requires kinase activity. These shared characteristics strengthen the idea that GluN2B is both necessary and sufficient for CaMKII synaptic translocation, although additional mediating factors may contribute (Colbran and Brown, 2004;Jalan-Sakrikar et al, 2012).…”

Metabolic Regulation of CaMKII Protein and Caspases in Xenopus laevis Egg Extracts

“…Work in the CNS has shown that CaMKII can interact with other proteins by diverse mechanisms (29,30). Our data show that CaMKII also interacts with the caspase 2-PP1 complex.…”

Actinin-4 Governs Dendritic Spine Dynamics and Promotes Their Remodeling by Metabotropic Glutamate Receptors

“…In immature motile protrusions, dissociation of this complex by group 1 mGluR activation may transiently decrease the proportion of CaMKII␤ bound to F-actin and enable protrusive motility and elongation. Actinins participate in the targeting of CaMKII␣ to F-actin (63), and CaMKII␤ knockdown reduces dendritic protrusion motility (43), similar to Actn4 down-regulation. Importantly, CaMKII-mediated effects on spine morphogenesis depend on its interaction with F-actin and not on its enzymatic activity (42).…”