These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: Characterization of a calcium-dependent calmodulin-binding domain in the 135-kD human protein 4.1 isoform.
    Author: Leclerc E, Vetter S.
    Journal: Eur J Biochem; 1998 Dec 01; 258(2):567-71. PubMed ID: 9874224.
    Abstract:
    The putative calmodulin binding domain of non-erythroid protein 4.1, previously suggested by Kelly et al. [Kelly, G. M., Zelus, B. D. & Moon, R. T. (1991) J. Biol. Chem. 266, 12469-12473] has been synthesized, and its binding to calmodulin has been studied by fluorescence spectroscopy. For this purpose, the peptide has been N-terminally dansylated. The 4.1 peptide Dns-Abu-S76RGLSRLFSSFLKRPKS92, binds calmodulin in a calcium-dependent way with high affinity (Kd = 23 +/- 6 nM). The peptide inhibits bovine-heart phosphodiesterase with an IC50 of 50 nM. Since the sequence of the peptide shows two putative consensus sites of phosphorylation by cAMP-dependent protein kinase or Ca2+-calmodulin protein-kinase II, the interaction of the two mono-phosphorylated peptides (P4.1 Ser(80-P) and P4.1 Ser(84-P)) and the di-phosphorylated peptide (P4.1 Ser(80-P)/Ser(84-P)) with calmodulin has been investigated. A decrease of affinity by a factor 1.5-8 has been observed for the phosphorylated peptides. CD measurements have shown an increase of the content of alpha helices in the peptides when bound to calmodulin.
    [Abstract] [Full Text] [Related] [New Search]