PEP-19, an intrinsically disordered regulator of calmodulin signaling.
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ABSTRACT:
SUBMITTER: Kleerekoper QK
PROVIDER: S-EPMC2658041 | biostudies-literature | 2009 Mar
REPOSITORIES: biostudies-literature
Publications
PEP-19, an intrinsically disordered regulator of calmodulin signaling.
Kleerekoper Quinn K QK Putkey John A JA
The Journal of biological chemistry 20081223 12
PEP-19 is a small calmodulin (CaM)-binding protein that greatly increases the rates of association and dissociation of Ca(2+) from the C-domain of CaM, an effect that is mediated by an acidic/IQ sequence in PEP-19. We show here using NMR that PEP-19 is an intrinsically disordered protein, but with residual structure localized to its acidic/IQ motif. We also show that the k(on) and k(off) rates for binding PEP-19 to apo-CaM are at least 50-fold slower than for binding to Ca(2+)-CaM. These data in ...[more]
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