John , Cheriyan and Madhavan , Mayadevi and Omkumar, RV. (2011) Calcium/Calmodulin Dependent Protein Kinase II Bound to NMDA Receptor 2B Subunit Exhibits Increased ATP Affinity and Attenuated Dephosphorylation. PloS one, 6 (3). ISSN San Francisco, CA : Public Library of Science

Text Calcium calmodulin (PLoS One).PDF Restricted to Registered users only Download (460Kb) | Request a copy

Abstract

Calcium/calmodulin dependent protein kinase II (CaMKII) is implicated to play a key role in learning and memory. NR2B subunit of N-methyl-D-aspartate receptor (NMDAR) is a high affinity binding partner of CaMKII at the postsynaptic membrane. NR2B binds to the T-site of CaMKII and modulates its catalysis. By direct measurement using isothermal titration calorimetry (ITC), we show that NR2B binding causes about 11 fold increase in the affinity of CaMKII for ATPγS, an analogue of ATP. ITC data is also consistent with an ordered binding mechanism for CaMKII with ATP binding the catalytic site first followed by peptide substrate. We also show that dephosphorylation of phospho-Thr286-α-CaMKII is attenuated when NR2B is bound to CaMKII. This favors the persistence of Thr286 autophosphorylated state of CaMKII in a CaMKII/phosphatase conjugate system in vitro. Overall our data indicate that the NR2B- bound state of CaMKII attains unique biochemical properties which could help in the efficient functioning of the proposed molecular switch supporting synaptic memory.

Item Type:	Article
Subjects:	Molecular Neurobiology
Depositing User:	Central Library RGCB
Date Deposited:	26 Apr 2017 08:56
Last Modified:	26 Apr 2017 08:56
URI:	http://rgcb.sciencecentral.in/id/eprint/353

Actions (login required)

View Item