3NAN

SR Ca(2+)-ATPase in the HnE2 state complexed with a Thapsigargin derivative Boc-(phi)Tg

3NAN の概要

• エントリーDOI: 10.2210/pdb3nan/pdb
• 関連するPDBエントリー: 2BY4 2C8K 3NAL 3NAM
• 分子名称: SERCA1a, POTASSIUM ION, MAGNESIUM ION, ... (5 entities in total)
• 機能のキーワード: serca, p-type atpase, ca2+-atpase, thapsigargin, prostate cancer, calcium transport, endoplasmic reticulum, hydrolase, ion transport, sarcoplasmic reticulum, transmembrane, transport
• 由来する生物種: Oryctolagus cuniculus (rabbit)
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 111344.17

構造登録者

Winther, A.M.L.,Sonntag, Y.,Olesen, C.,Moller, J.V.,Nissen, P. (登録日: 2010-06-02, 公開日: 2010-06-30, 最終更新日: 2024-10-30)

主引用文献

Winther, A.M.L.,Liu, H.,Sonntag, Y.,Olesen, C.,le Maire, M.,Soehoel, H.,Olsen, C.E.,Christensen, S.B.,Nissen, P.,Moller, J.V.
Critical roles of hydrophobicity and orientation of side chains for inactivation of sarcoplasmic reticulum Ca2+-ATPase with thapsigargin and thapsigargin analogs
J.Biol.Chem., 285:28883-28892, 2010

PubMed Abstract: Thapsigargin (Tg), a specific inhibitor of sarco/endoplasmic Ca(2+)-ATPases (SERCA), binds with high affinity to the E2 conformation of these ATPases. SERCA inhibition leads to elevated calcium levels in the cytoplasm, which in turn induces apoptosis. We present x-ray crystallographic and intrinsic fluorescence data to show how Tg and chemical analogs of the compound with modified or removed side chains bind to isolated SERCA 1a membranes. This occurs by uptake via the membrane lipid followed by insertion into a resident intramembranous binding site with few adaptative changes. Our binding data indicate that a balanced hydrophobicity and accurate positioning of the side chains, provided by the central guaianolide ring structure, defines a pharmacophore of Tg that governs both high affinity and access to the protein-binding site. Tg analogs substituted with long linkers at O-8 extend from the binding site between transmembrane segments to the putative N-terminal Ca(2+) entry pathway. The long chain analogs provide a rational basis for the localization of the linker, the presence of which is necessary for enabling prostate-specific antigen to cleave peptide-conjugated prodrugs targeting SERCA of cancer cells (Denmeade, S. R., Jakobsen, C. M., Janssen, S., Khan, S. R., Garrett, E. S., Lilja, H., Christensen, S. B., and Isaacs, J. T. (2003) J. Natl. Cancer Inst. 95, 990-1000). Our study demonstrates the usefulness of a simple in vitro system to test and direct development toward the formulation of new Tg derivatives with improved properties for SERCA targeting. Finally, we propose that the Tg binding pocket may be a regulatory site that, for example, is sensitive to cholesterol.

PubMed: 20551329
DOI: 10.1074/jbc.M110.136242

実験手法

X-RAY DIFFRACTION (3.1 Å)