3E3R

Crystal structure and biochemical characterization of recombinant human calcyphosine delineates a novel EF-hand-containing protein family

Summary for 3E3R

• Entry DOI: 10.2210/pdb3e3r/pdb
• Descriptor: Calcyphosin, CALCIUM ION (3 entities in total)
• Functional Keywords: human calcyphosine, ef-hand, phosphoprotein, calcium binding protein
• Biological source: Homo sapiens (Human)
• Cellular location: Cytoplasm: Q13938
• Total number of polymer chains: 2
• Total formula weight: 45324.92

Authors

Dong, H. (deposition date: 2008-08-07, release date: 2008-08-26, Last modification date: 2024-03-20)

Primary citation

Dong, H.,Li, X.,Lou, Z.,Xu, X.,Su, D.,Zhou, X.,Zhou, W.,Bartlam, M.,Rao, Z.
Crystal-structure and biochemical characterization of recombinant human calcyphosine delineates a novel EF-hand-containing protein family
J.Mol.Biol., 383:455-464, 2008

PubMed Abstract: Calcyphosine is an EF-hand protein involved in both Ca(2+)-phosphatidylinositol and cyclic AMP signal cascades, as well as in other cellular functions. The crystal structure of Ca(2+)-loaded calcyphosine was determined up to 2.65 A resolution and reveals a protein containing two pairs of Ca(2+)-binding EF-hand motifs. Calcyphosine shares a highly similar overall topology with calmodulin. However, there are striking differences between EF-hand 4, both N-terminal and C-terminal regions, and interdomain linkers. The C-terminal domain of calcyphosine possesses a large hydrophobic pocket in the presence of calcium ions that might be implicated in ligand binding, while its N-terminal hydrophobic pocket is almost shielded by an additional terminal helix. Calcyphosine is largely monomeric, regardless of the presence of Ca(2+). Differences in structure, oligomeric state in the presence and in the absence of Ca(2+), a highly conserved sequence with low similarity to other proteins, and phylogeny define a new EF-hand-containing family of calcyphosine proteins that extends from arthropods to humans.

PubMed: 18775726
DOI: 10.1016/j.jmb.2008.08.048

Experimental method

X-RAY DIFFRACTION (2.65 Å)