Holoenzyme and Subunit Structure

Copyright 1996 by Academic Press, Inc. All rights of reproduction in any form reserved. 

HAROLD A. SINGER, S. THOMAS ABRAHAM, AND CHARLES M. SCHWORER 

FIGURE 1 (A) CaM-kinase II subunit structures. Open boxes indicate conserved domains and 

1991) or expression of mutant kinase subunits truncated in the regulatory region (Cruzalegui et al., 1992) generates a constitutively active monomeric kinase activity, hence the name for the conserved association domain, which is inferred to be required for formation of the holoenzyme. Electron microscopic imaging of purified brain CaM-kinase II molecules suggests that the holoenzyme has the shape of a rosette (similar to that depicted in Fig. 4), consistent with the association of 8-10 dumbbell -shaped kinase subunits (Kanaseki etal, 1991). 

differing in variable domain nucleic acid sequence, have been identified. In addition, Mayer et al. (1993) have described 8-subunit variants lacking the 

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