Localization of the linker domain of Ca2+/calmodulin-dependent protein kinase II.
Electron micrographs of rotary shadowed replicas of alpha-Ca2+/calmodulin-dependent protein kinase II reveal a flower-shaped multimeric molecule with a central particle surrounded by 8-10 smaller peripheral particles. Peripheral particles are attached to the central particle by thin arms or "linkers." Movement of peripheral particles to contact each other for autophosphorylation is likely to involve these linkers. It has generally been accepted that the segment 317-328 of the alpha-subunit constitutes the linker domain. In the present study we test this assumption by generating a mutant lacking the proposed sequence. The mutant has biochemical and morphological properties similar to those of the wild type, and a thin linker is occasionally observed in replicas from either type. The results indicate that the deleted sequence does not correspond to the linker domain. This conclusion, combined with observations from two recent studies which identify the C-terminal domain involved in oligomerization, narrows down the location of the linker domain within the sequence 330-354.
Dosemeci
A
A
Laboratory of Neurobiology, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland 20892, USA. ayse@codon.nih.gov
Reese
T S
TS
Petersen
J D
JD
Choi
C
C
Beushausen
S
S
D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D054732:Calcium-Calmodulin-Dependent Protein Kinase Type 2; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000737:chemistry* / Q000378:metabolism / Q000648:ultrastructure*; D002460:Cell Line; D046911:Macromolecular Substances; D051379:Mice; D008854:Microscopy, Electron; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D010446:Peptide Fragments / Q000737:chemistry / Q000648:ultrastructure; D010766:Phosphorylation; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism / Q000648:ultrastructure; D018411:Spodoptera; D014162:Transfection
D046911:Macromolecular Substances; D010446:Peptide Fragments; D011994:Recombinant Proteins; D054732:Calcium-Calmodulin-Dependent Protein Kinase Type 2; D017871:Calcium-Calmodulin-Dependent Protein Kinases