ISSN:
1573-4919
Keywords:
protein kinase CK2
;
casein kinase-2
;
autophosphorylation
;
polybase compounds
;
dimerization
;
β subunit
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Chemistry and Pharmacology
,
Medicine
Notes:
Abstract Synthetic peptides reproducing the amino and carboxyl terminal region of CK2 β subunit have been analyzed for their ability to mimic different properties of full length β subunit. Peptide β[1-77], containing both the autophosphorylation site and the down-regulatory domain 55-64, is readily phosphorylated by a subunit whose activity is concomitantly inhibited. Such inhibition is accompanied by a weak interaction detectable by BIAcore sensograms but not by far Western blots, and is not reversed by polylysine which conversely overcome inhibition of calmodulin phosphorylation by full length β subunit. A strong interaction with α is observed with β[155-215] but not with its shorter derivative β[170-215] as judged from far Western blotting and sucrose gradient ultracentrifugation analysis. Both peptides, however, affect the regular interaction between α and β subunits altering the autophosphorylation pattern and responsiveness to salt. β[155-215], unlike β[170-215] tends to aggregate more readily than full length β subunit. This behaviour which is reminiscent of the homodimerization of full length β subunit, would indicate that tight self-association of β[155-215] crucially depends on residues in the 155-170 sequence. Failure of β[1-77] fragment to mediate responsiveness to polybasic peptides and accentuated self-association propensity of β[155-215] suggest that other structural elements between the sequences 1-77 and 155-215 are required in order to confer optimal functionality to the β subunit.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1006822632216
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