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Daily rhythms are a constant part of life. This special Focus issue explores the molecular mechanisms that underlie the generation of circadian dynamics.
Here, we announce two policy changes across Nature journals: data-availability statements in all published papers and official Worldwide Protein Data Bank (wwPDB) validation reports for peer review.
In a common yet effective analogy, a cell can be compared to a fortified city, in which lipid membranes form the defensive walls, and membrane proteins function as gates and checkpoints that control the transit of molecules and information across these walls. We evoke this concept on the cover of this special Focus on Membrane Proteins.
Wayne Hendrickson discusses the consortium efforts and developments in methodology that in recent years have allowed unprecedented advances in atomic-structure determination of membrane proteins.
