This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.
Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.
2f86
From Proteopedia
The Association Domain of C. elegans CaMKII
Overview
Ca2+/calmodulin activated protein kinase II (CaMKII) is an oligomeric protein kinase with a unique holoenyzme architecture. The subunits of CaMKII are bound together into the holoenzyme by the association domain, a C-terminal region of approximately 140 residues in the CaMKII polypeptide. Single particle analyses of electron micrographs have suggested previously that the holoenyzme forms a dodecamer that contains two stacked 6-fold symmetric rings. In contrast, a recent crystal structure of the isolated association domain of mouse CaMKIIalpha has revealed a tetradecameric assembly with two stacked 7-fold symmetric rings. In this study, we have determined the crystal structure of the Caenorhabditis elegans CaMKII association domain and it too forms a tetradecamer. We also show by electron microscopy that in its fully assembled form the CaMKII holoenzyme is a dodecamer but without the kinase domains, either from expression of the isolated association domain in bacteria or following their removal by proteolysis, the association domains form a tetradecamer. We speculate that the holoenzyme is held in its 6-fold symmetric state by the interactions of the N-terminal approximately 1-335 residues and that the removal of this region allows the association domain to convert into a more stable 7-fold symmetric form.
About this Structure
2F86 is a Single protein structure of sequence from Caenorhabditis elegans. Full crystallographic information is available from OCA.
Reference
Oligomerization states of the association domain and the holoenyzme of Ca2+/CaM kinase II., Rosenberg OS, Deindl S, Comolli LR, Hoelz A, Downing KH, Nairn AC, Kuriyan J, FEBS J. 2006 Feb;273(4):682-94. PMID:16441656 Page seeded by OCA on Sun May 4 03:34:40 2008
