1qls
From Proteopedia
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==Overview== | ==Overview== | ||
| - | Background: S100C (S100A11) is a member of the S100 calcium-binding, protein family, the function of which is not yet entirely clear, but may, include cytoskeleton assembly and dynamics. S100 proteins consist of two, EF-hand calcium-binding motifs, connected by a flexible loop. Like several, other members of the family, S100C forms a homodimer. A number of S100, proteins form complexes with annexins, another family of calcium-binding, proteins that also bind to phospholipids. Structural studies have been, undertaken to understand the basis of these interactions. Results: We have, solved the crystal structure of a complex of calcium-loaded S100C with a, synthetic peptide that corresponds to the first 14 residues of the annexin, I N terminus at 2.3 A resolution. We find a stoichiometry of ... | + | Background: S100C (S100A11) is a member of the S100 calcium-binding, protein family, the function of which is not yet entirely clear, but may, include cytoskeleton assembly and dynamics. S100 proteins consist of two, EF-hand calcium-binding motifs, connected by a flexible loop. Like several, other members of the family, S100C forms a homodimer. A number of S100, proteins form complexes with annexins, another family of calcium-binding, proteins that also bind to phospholipids. Structural studies have been, undertaken to understand the basis of these interactions. Results: We have, solved the crystal structure of a complex of calcium-loaded S100C with a, synthetic peptide that corresponds to the first 14 residues of the annexin, I N terminus at 2.3 A resolution. We find a stoichiometry of one peptide, per S100C monomer, the entire complex structure consisting of two peptides, per S100C dimer. Each peptide, however, interacts with both monomers of, the S100C dimer. The two S100C molecules of the dimer are linked by a, disulphide bridge. The structure is surprisingly close to that of the, p11-annexin II N-terminal peptide complex solved previously. We have, performed competition experiments to try to understand the specificity of, the S100-annexin interaction. Conclusions: By solving the structure of a, second annexin N terminus-S100 protein complex, we confirmed a novel mode, of interaction of S100 proteins with their target peptides; there is a, one-to-one stoichiometry, where the dimeric structure of the S100 protein, is, nevertheless, essential for complex formation. Our structure can, provide a model for a Ca(2+)-regulated annexin I-S100C heterotetramer, possibly involved in crosslinking membrane surfaces or organising, membranes during certain fusion events. |
==About this Structure== | ==About this Structure== | ||
| - | 1QLS is a | + | 1QLS is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens] and [http://en.wikipedia.org/wiki/Sus_scrofa Sus scrofa] with CA and ACE as [http://en.wikipedia.org/wiki/ligands ligands]. Structure known Active Sites: CA1 and CA2. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=1QLS OCA]. |
==Reference== | ==Reference== | ||
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[[Category: s100 family]] | [[Category: s100 family]] | ||
| - | ''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Mon Nov 5 14:39:31 2007'' |
Revision as of 12:34, 5 November 2007
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S100C (S100A11),OR CALGIZZARIN, IN COMPLEX WITH ANNEXIN I N-TERMINUS
Overview
Background: S100C (S100A11) is a member of the S100 calcium-binding, protein family, the function of which is not yet entirely clear, but may, include cytoskeleton assembly and dynamics. S100 proteins consist of two, EF-hand calcium-binding motifs, connected by a flexible loop. Like several, other members of the family, S100C forms a homodimer. A number of S100, proteins form complexes with annexins, another family of calcium-binding, proteins that also bind to phospholipids. Structural studies have been, undertaken to understand the basis of these interactions. Results: We have, solved the crystal structure of a complex of calcium-loaded S100C with a, synthetic peptide that corresponds to the first 14 residues of the annexin, I N terminus at 2.3 A resolution. We find a stoichiometry of one peptide, per S100C monomer, the entire complex structure consisting of two peptides, per S100C dimer. Each peptide, however, interacts with both monomers of, the S100C dimer. The two S100C molecules of the dimer are linked by a, disulphide bridge. The structure is surprisingly close to that of the, p11-annexin II N-terminal peptide complex solved previously. We have, performed competition experiments to try to understand the specificity of, the S100-annexin interaction. Conclusions: By solving the structure of a, second annexin N terminus-S100 protein complex, we confirmed a novel mode, of interaction of S100 proteins with their target peptides; there is a, one-to-one stoichiometry, where the dimeric structure of the S100 protein, is, nevertheless, essential for complex formation. Our structure can, provide a model for a Ca(2+)-regulated annexin I-S100C heterotetramer, possibly involved in crosslinking membrane surfaces or organising, membranes during certain fusion events.
About this Structure
1QLS is a Protein complex structure of sequences from Homo sapiens and Sus scrofa with CA and ACE as ligands. Structure known Active Sites: CA1 and CA2. Full crystallographic information is available from OCA.
Reference
Structural basis of the Ca(2+)-dependent association between S100C (S100A11) and its target, the N-terminal part of annexin I., Rety S, Osterloh D, Arie JP, Tabaries S, Seeman J, Russo-Marie F, Gerke V, Lewit-Bentley A, Structure. 2000 Feb 15;8(2):175-84. PMID:10673436
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