1WPG

Crystal structure of the SR CA2+-ATPase with MGF4

Summary for 1WPG

• Entry DOI: 10.2210/pdb1wpg/pdb
• Related: 1IWO 1SU4 1VFP 1WPE
• Descriptor: Sarcoplasmic/endoplasmic reticulum calcium ATPase 1, MAGNESIUM ION, SODIUM ION, ... (7 entities in total)
• Functional Keywords: membrane protein, p-type atpase, had fold, hydrolase, hydrolase-hydrolase inhibitor complex, hydrolase/hydrolase inhibitor
• Biological source: Oryctolagus cuniculus (rabbit)
• Cellular location: Endoplasmic reticulum membrane; Multi-pass membrane protein: P04191
• Total number of polymer chains: 4
• Total formula weight: 443409.73

Authors

Toyoshima, C.,Nomura, H.,Tsuda, T. (deposition date: 2004-09-02, release date: 2004-10-05, Last modification date: 2024-10-23)

Primary citation

Toyoshima, C.,Nomura, H.,Tsuda, T.
Lumenal gating mechanism revealed in calcium pump crystal structures with phosphate analogues
Nature, 432:361-368, 2004

PubMed Abstract: P-type ion transporting ATPases are ATP-powered ion pumps that establish ion concentration gradients across biological membranes. Transfer of bound cations to the lumenal or extracellular side occurs while the ATPase is phosphorylated. Here we report at 2.3 A resolution the structure of the calcium-ATPase of skeletal muscle sarcoplasmic reticulum, a representative P-type ATPase that is crystallized in the absence of Ca2+ but in the presence of magnesium fluoride, a stable phosphate analogue. This and other crystal structures determined previously provide atomic models for all four principal states in the reaction cycle. These structures show that the three cytoplasmic domains rearrange to move six out of ten transmembrane helices, thereby changing the affinity of the Ca2+-binding sites and the gating of the ion pathway. Release of ADP triggers the opening of the lumenal gate and release of phosphate its closure, effected mainly through movement of the A-domain, the actuator of transmembrane gates.

PubMed: 15448704
DOI: 10.1038/nature02981

Experimental method

X-RAY DIFFRACTION (2.3 Å)