Regulation of neuronal excitability in Drosophila by constitutively active CaMKII.
The ability of calcium/calmodulin-dependent protein kinase II (CaMKII) to become calcium independent after autophosphorylation makes this enzyme a temporal marker of neuronal activity. Here we show that the calcium-independent form of CaMKII has unique effects on larval viability, locomotion, and neuronal excitability in Drosophila. Expression of constitutively active T287D, but not calcium-dependent T287A, mutant CaMKII in Drosophila neurons resulted in decreased viability, behavioral defects, and failure of action potential propagation. The actions of T287D may be mediated, at least in part, by increased potassium conductances. Expression of T287D CaMKII also stimulated an increase in the number of boutons at the larval neuromuscular junction, but did not affect the mechanics of release. This study defines a role for autophosphorylation of CaMKII in the regulation of multiple neuronal functions including the intrinsic properties of neurons.
Park
Demian
D
Department of Biology and Volen Center for Complex Systems, Brandeis University, Waltham, Massachusetts 02254-9110, USA.
Coleman
Melissa J
MJ
Hodge
James J L
JJ
Budnik
Vivian
V
Griffith
Leslie C
LC
D000779:Anesthetics, Local / Q000494:pharmacology; D000818:Animals; D030801:Animals, Genetically Modified; D054732:Calcium-Calmodulin-Dependent Protein Kinase Type 2; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000235:genetics / Q000378:metabolism*; D002147:Calmodulin / Q000378:metabolism; D004268:DNA-Binding Proteins; D004330:Drosophila / Q000201:enzymology* / Q000254:growth & development; D005071:Evoked Potentials / Q000187:drug effects / Q000502:physiology; D005260:Female; D005656:Fungal Proteins / Q000235:genetics; D015971:Gene Expression Regulation, Enzymologic; D007814:Larva / Q000201:enzymology; D008297:Male; D009043:Motor Activity / Q000502:physiology; D009046:Motor Neurons / Q000201:enzymology*; D009132:Muscles / Q000201:enzymology; D009469:Neuromuscular Junction / Q000201:enzymology; D010641:Phenotype; D010766:Phosphorylation; D011188:Potassium / Q000378:metabolism; D017729:Presynaptic Terminals / Q000201:enzymology; D029701:Saccharomyces cerevisiae Proteins; D015222:Sodium Channels / Q000235:genetics; D013779:Tetrodotoxin / Q000494:pharmacology; D014157:Transcription Factors / Q000235:genetics; D019076:Transgenes / Q000502:physiology
D000779:Anesthetics, Local; D002147:Calmodulin; D004268:DNA-Binding Proteins; D005656:Fungal Proteins; C052130:GAL4 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D015222:Sodium Channels; D014157:Transcription Factors; D013779:Tetrodotoxin; D054732:Calcium-Calmodulin-Dependent Protein Kinase Type 2; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D011188:Potassium