In this study the authors have, for the first time, quantified DNA replication origin licensing dynamics and distribution in single cells at subnuclear resolution. The cell cycle and DNA replication fields have long appreciated that origin licensing is both absolutely essential for replication and that licensing is strictly confined to G1 phase. The biochemical process of origin licensing- which is the DNA loading of MCM complexes- is known in considerable detail. What has never been explored in any system, is the dynamics of origin licensing itself. Here the authors define the dynamics of human MCM loading at different times within G1 in both euchromatin and heterochromatin, and explore the consequences of those dynamics for genome stability.
NAR’s Breakthrough Articles present high-impact studies answering long-standing questions in the field of nucleic acids research and/or opening up new areas and mechanistic hypotheses for investigation. These articles are chosen by the Editors on the recommendation of Editorial Board Members and Referees. Articles are accompanied by a brief synopsis explaining the findings of the paper and where they fit in the broader context of nucleic acids research. They represent the very best papers published at NAR.
Parasites of viruses, often referred to as satellites, are found in all domains of life and have been co-opted for host defense across diverse virus-host systems multiple independent times. This study describes the mechanism by which such an element prevents a bacterial virus (a 'phage') from otherwise infecting Vibrio cholera and related bacteria. The study is of broad interest to investigators with interests in phage-host interactions and microbial genetics.
The AlphaFold Protein Structure Database (AlphaFold DB, https://alphafold.ebi.ac.uk) is an openly accessible, extensive database of high-accuracy protein-structure predictions. Powered by AlphaFold v2.0 of DeepMind, it has enabled an unprecedented expansion of the structural coverage of the known protein-sequence space. AlphaFold DB provides programmatic access to and interactive visualization of predicted atomic coordinates, per-residue and pairwise model-confidence estimates and predicted aligned errors. The initial release of AlphaFold DB contains over 360,000 predicted structures across 21 model-organism proteomes, which will soon be expanded to cover most of the (over 100 million) representative sequences from the UniRef90 data set.
