PDBsum entry 2bdw

Transferase

PDB id: 2bdw

Contents

Protein chains

309 a.a.

Waters ×431

References listed in PDB file

Key reference

Title

Structure of the autoinhibited kinase domain of camkii and saxs analysis of the holoenzyme.

Authors

O.S.Rosenberg, S.Deindl, R.J.Sung, A.C.Nairn, J.Kuriyan.

Ref.

Cell, 2005, 123, 849-860. [DOI no: 10.1016/j.cell.2005.10.029]

PubMed id

16325579

Abstract

Ca2+/calmodulin-dependent protein kinase-II (CaMKII) is unique among protein kinases for its dodecameric assembly and its complex response to Ca2+. The crystal structure of the autoinhibited kinase domain of CaMKII, determined at 1.8 A resolution, reveals an unexpected dimeric organization in which the calmodulin-responsive regulatory segments form a coiled-coil strut that blocks peptide and ATP binding to the otherwise intrinsically active kinase domains. A threonine residue in the regulatory segment, which when phosphorylated renders CaMKII calmodulin independent, is held apart from the catalytic sites by the organization of the dimer. This ensures a strict Ca2+ dependence for initial activation. The structure of the kinase dimer, when combined with small-angle X-ray scattering data for the holoenzyme, suggests that inactive CaMKII forms tightly packed autoinhibited assemblies that convert upon activation into clusters of loosely tethered and independent kinase domains.

Figure 2.
Figure 2. Details of the Interaction between the Kinase Domain and the Regulatory Segment

Figure 3.
Figure 3. An Allosteric Mechanism Affecting the ATP Binding Site

The above figures are reprinted by permission from Cell Press: Cell (2005, 123, 849-860) copyright 2005.