About this Research Topic
Membrane proteins perform many important biological processes such as ion transport, electrical excitability, cell communication, signal transduction and protein secretion, and are associated with diseases like heart disease, cancer, neurodegenerative diseases etc. Importantly, ~30% of any given genome codes for membrane proteins and ~60% of available drugs target membrane proteins. Structural determination of membrane proteins at the atomic level is quite challenging due to poor expression, low purification yields and the low success rate of forming well-ordered 3D crystals. Despite recent successes in determining the high-resolution structures of membrane proteins, the molecular understanding of the biological functions of membrane proteins is limited due to lack of structural dynamics information that is associated with different functional states in a physiologically-relevant membrane set-up. This is because the efficient biological function of a protein is generally performed by traversing complex conformational energy landscapes with inbuilt dynamic timescales. The dynamic timescales could range from picosecond to millisecond to seconds depending on the particular proteins’ function and this dynamic change could result from i) fast (picosecond) local atomic fluctuations ii) faster (nanosecond) motions of whole segments (segmental mobility) and iii) collective, slower (microsecond to millisecond) motions. Importantly, recent experimental evidence suggests that these dynamic features are directly connected to the function of membrane proteins. This emphasizes that the initial structure determination of a protein is only the beginning of the quest to decipher how it actually works and that elucidating the interplay between structure and dynamics can lead to novel mechanistic insights into the complex functionality of membrane proteins. The ‘Structural Dynamics of Membrane Proteins’ theme aims to collect articles/reviews mainly, but not restricted to, utilizing sophisticated structural and dynamic approaches such as X-ray crystallography, cryo-EM, NMR, site-directed labeling techniques (EPR, IR and fluorescence), electrophysiology, MD simulations etc. to comprehensively understand the lipid-protein interactions in membranes as well as to unravel the mechanisms of action of membrane proteins at the molecular level.