1zfs
From Proteopedia
OCA (Talk | contribs)
(New page: 200px<br /><applet load="1zfs" size="450" color="white" frame="true" align="right" spinBox="true" caption="1zfs" /> '''Solution structure of S100A1 bound to calciu...)
Next diff →
Revision as of 05:18, 21 November 2007
|
Solution structure of S100A1 bound to calcium
Overview
S100A1 is an EF-hand-containing Ca(2+)-binding protein that undergoes a, conformational change upon binding calcium as is necessary to interact, with protein targets and initiate a biological response. To better, understand how calcium influences the structure and function of S100A1, the three-dimensional structure of calcium-bound S100A1 was determined by, multidimensional NMR spectroscopy and compared to the previously, determined structure of apo. In total, 3354 nuclear Overhauser, effect-derived distance constraints, 240 dihedral constraints, 160, hydrogen bond constraints, and 362 residual dipolar coupling restraints, derived from a series of two-dimensional, three-dimensional, and, four-dimensional NMR experiments were used in its structure determination, (>21 constraints per residue). As with other dimeric S100 proteins, S100A1, is a symmetric homodimer with helices 1, 1', 4, and 4' associating into an, X-type four-helix bundle at the dimer interface. Within each subunit there, are four alpha-helices and a short antiparallel beta-sheet typical of two, helix-loop-helix EF-hand calcium-binding domains. The addition of calcium, did not change the interhelical angle of helices 1 and 2 in the pseudo, EF-hand significantly; however, there was a large reorientation of helix 3, in the typical EF-hand. The large conformational change exposes a, hydrophobic cleft, defined by residues in the hinge region, the C, terminus, and regions of helix 3, which are important for the interaction, between S100A1 and a peptide (TRTK-12) derived from the actin-capping, protein CapZ.
About this Structure
1ZFS is a Single protein structure of sequence from Rattus norvegicus with CA as ligand. Full crystallographic information is available from OCA.
Reference
The three-dimensional solution structure of Ca(2+)-bound S100A1 as determined by NMR spectroscopy., Wright NT, Varney KM, Ellis KC, Markowitz J, Gitti RK, Zimmer DB, Weber DJ, J Mol Biol. 2005 Oct 21;353(2):410-26. PMID:16169012
Page seeded by OCA on Wed Nov 21 07:25:35 2007
