Membrane proteins by ESR
Detergents vs. membrane vesicles vs. nanodisc
Structure and regulation of the BsYetJ calcium channel
The endoplasmic reticulum (ER) serves as the major intracellular calcium store. The release of calcium from this store regulates a variety of cellular functions, hence playing a key role in regulating apoptosis. The transmembrane BAX inhibitor-1 motif-containing 6 (TMBIM6) is an evolutionarily conserved multifunctional ER membrane protein that mediates calcium homeostasis to protect against apoptosis and ER stress. We study a bacterial homolog of TMBIM6 and report several previously unidentified conformational substates involved in the calcium transport process. Our findings stimulate a model of calcium-release channel showing that membrane protein functioning requires the interconversion between distinct conformations in preexisting conformational equilibria.
Nanodisc-based approach to enhance DEER measurements
We use spin-nanodisc to improve SNR of DEER signals for conventional membrane protein study. The new approach enables a significant improvement in the distance resolution obtainable from the DEER result by Tikhonov method.
ESR reveals lipid-dependent conformational changes of membrane proteins
Membrane proteins are incorporated in various environments, including detergent, membrane vesicles, and nanodisc. ESR distance measurements show that the protein behave differently with environments.