Structural highlights
Function
[S10A1_RAT] Weakly binds calcium but binds zinc very tightly-distinct binding sites with different affinities exist for both ions on each monomer. Physiological concentrations of potassium ion antagonize the binding of both divalent cations, especially affecting high-affinity calcium-binding sites.
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
In heart and skeletal muscle an S100 protein family member, S100A1, binds to the ryanodine receptor (RyR) and promotes Ca(2+) release. Using competition binding assays, we further characterized this system in skeletal muscle and showed that Ca(2+)-S100A1 competes with Ca(2+)-calmodulin (CaM) for the same binding site on RyR1. In addition, the NMR structure was determined for Ca(2+)-S100A1 bound to a peptide derived from this CaM/S100A1 binding domain, a region conserved in RyR1 and RyR2 and termed RyRP12 (residues 3616-3627 in human RyR1). Examination of the S100A1-RyRP12 complex revealed residues of the helical RyRP12 peptide (Lys-3616, Trp-3620, Lys-3622, Leu-3623, Leu-3624, and Lys-3626) that are involved in favorable hydrophobic and electrostatic interactions with Ca(2+)-S100A1. These same residues were shown previously to be important for RyR1 binding to Ca(2+)-CaM. A model for regulating muscle contraction is presented in which Ca(2+)-S100A1 and Ca(2+)-CaM compete directly for the same binding site on the ryanodine receptor.
S100A1 and calmodulin compete for the same binding site on ryanodine receptor.,Wright NT, Prosser BL, Varney KM, Zimmer DB, Schneider MF, Weber DJ J Biol Chem. 2008 Sep 26;283(39):26676-83. Epub 2008 Jul 23. PMID:18650434[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Wright NT, Prosser BL, Varney KM, Zimmer DB, Schneider MF, Weber DJ. S100A1 and calmodulin compete for the same binding site on ryanodine receptor. J Biol Chem. 2008 Sep 26;283(39):26676-83. Epub 2008 Jul 23. PMID:18650434 doi:10.1074/jbc.M804432200