4N5X

Crystal structure of N-terminal calmodulin-like Calcium sensor of human mitochondrial ATP-Mg/Pi carrier SCaMC1

4N5X の概要

• エントリーDOI: 10.2210/pdb4n5x/pdb
• 分子名称: Calcium-binding mitochondrial carrier protein SCaMC-1, CALCIUM ION, DI(HYDROXYETHYL)ETHER, ... (4 entities in total)
• 機能のキーワード: calmodulin, calcium sensor, mitochondrial inner membrane, calcium-binding protein
• 由来する生物種: Homo sapiens (human)
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 23239.00

構造登録者

Yang, Q.,Bruschweiler, S.,Chou, J. (登録日: 2013-10-10, 公開日: 2013-12-18, 最終更新日: 2023-09-20)

主引用文献

Yang, Q.,Bruschweiler, S.,Chou, J.J.
A Self-Sequestered Calmodulin-like Ca(2+) Sensor of Mitochondrial SCaMC Carrier and Its Implication to Ca(2+)-Dependent ATP-Mg/Pi Transport.
Structure, 22:209-217, 2014

PubMed Abstract: The mitochondrial carriers play essential roles in energy metabolism. The short Ca²⁺-binding mitochondrial carrier (SCaMC) transports ATP-Mg in exchange for Pi and is important for activities that depend on adenine nucleotides. SCaMC adopts, in addition to the transmembrane domain (TMD) that transports solutes, an extramembrane N-terminal domain (NTD) that regulates solute transport in a Ca²⁺-dependent manner. Crystal structure of the Ca²⁺-bound NTD reveals a compact architecture in which the functional EF hands are sequestered by an endogenous helical segment. Nuclear magnetic resonance (NMR) relaxation rates indicated that removal of Ca²⁺ from NTD results in a major conformational switch from the rigid and compact Ca²⁺-bound state to the dynamic and loose apo state. Finally, we showed using surface plasmon resonance and NMR titration experiments that free apo NTDs could specifically interact with liposome-incorporated TMD, but that Ca²⁺ binding drastically weakened the interaction. Our results together provide a molecular explanation for Ca²⁺-dependent ATP-Mg flux in mitochondria.

PubMed: 24332718
DOI: 10.1016/j.str.2013.10.018

実験手法

X-RAY DIFFRACTION (2.1 Å)