7BT2

Crystal structure of the SERCA2a in the E2.ATP state

Summary for 7BT2

• Entry DOI: 10.2210/pdb7bt2/pdb
• Descriptor: Sarcoplasmic/endoplasmic reticulum calcium ATPase 2, ADENOSINE-5'-TRIPHOSPHATE, POTASSIUM ION, ... (6 entities in total)
• Functional Keywords: p-type atpase, ca2+-atpase, hydrolase
• Biological source: Homo sapiens (Human)
• Total number of polymer chains: 1
• Total formula weight: 113614.77

Authors

Kabashima, Y.,Ogawa, H.,Nakajima, R.,Toyoshima, C. (deposition date: 2020-03-31, release date: 2020-07-15, Last modification date: 2024-10-16)

Primary citation

Kabashima, Y.,Ogawa, H.,Nakajima, R.,Toyoshima, C.
What ATP binding does to the Ca2+pump and how nonproductive phosphoryl transfer is prevented in the absence of Ca2.
Proc.Natl.Acad.Sci.USA, 117:18448-18458, 2020

PubMed Abstract: Under physiological conditions, most Ca-ATPase (SERCA) molecules bind ATP before binding the Ca transported. SERCA has a high affinity for ATP even in the absence of Ca, and ATP accelerates Ca binding at pH values lower than 7, where SERCA is in the E2 state with low-affinity Ca-binding sites. Here we describe the crystal structure of SERCA2a, the isoform predominant in cardiac muscle, in the E2·ATP state at 3.0-Å resolution. In the crystal structure, the arrangement of the cytoplasmic domains is distinctly different from that in canonical E2. The A-domain now takes an E1 position, and the N-domain occupies exactly the same position as that in the E1·ATP·2Ca state relative to the P-domain. As a result, ATP is properly delivered to the phosphorylation site. Yet phosphoryl transfer never takes place without the filling of the two transmembrane Ca-binding sites. The present crystal structure explains what ATP binding itself does to SERCA and how nonproductive phosphorylation is prevented in E2.

PubMed: 32675243
DOI: 10.1073/pnas.2006027117

Experimental method

X-RAY DIFFRACTION (3.00002849524 Å)