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How animals coordinate the production of multimodal signals is poorly understood. Here, authors shows how a single neural circuit integrates social cues and motivational state to orchestrate signal production across modalities.

The authors present a sample preparation method for biological cryo-EM that offers advantages over existing blotting methods, such as reduced variability, no need for expensive instrumentation and improved particle orientation distributions.

Structures of actin-like ParM filaments at near-atomic resolution and their arrangements into doublets reveal how subunits and filaments come together to segregate low-copy-number plasmid R1 in Escherichia coli, producing the simplest known mitotic machinery.

Bacteria and archaea have intracellular cytoskeletons built from dynamic protein filaments. In this Review, Wagstaff and Löwe discuss how these linear protein polymers are used to organize other molecules in prokaryotic cells.

The Nitrosopumilus maritimus surface layer (S-layer) concentrates ammonium ions on its cell-facing side, acting as a multichannel sieve on the cell membrane.

Bacterial divisome protein FtsA, which is an actin homologue, forms double filaments following binding to FtsN, and like MreB, an actin homologue in the elongasome, the curvature-sensing double filaments guide peptidoglycan insertion for cell division.

During archaeal cell division, proteins containing photosynthetic reaction centre domains enable the formation of a defined cell division plane by direct interaction with SepF.

The cryogenic electron microscopy structure of the Pseudomonas aeruginosa cell division complex and antibiotic drug target, FtsWIQBL, suggests a possible activation mechanism.

The ESCRT pathway is crucial for membrane remodelling in eukaryotes. Here, Hatano et al. explore the phylogeny, structure, and biochemistry of homologues of the ESCRT machinery and the associated ubiquitylation system in Asgard archaea, the closest living relatives of eukaryotes.

Fibres formed by protein TasA are important components of the extracellular matrix in biofilms developed by the bacterium Bacillus subtilis. Here, Böhning et al. use electron cryomicroscopy and other techniques to show how TasA globular monomers assemble through donor-strand exchange into β-sheet-rich fibres, which in turn assemble into bundles.

Epigenetic information is transmitted from mother to daughter cells through mitosis. Here, the authors isolate native chromosomes from metaphase-arrested cells and perform LC-MS/MS to identify chromosome-bound proteins in pluripotent stem cells during mitosis and reveal that PRC2, DNA methylation and Mecp2 are required to maintain chromosome compaction.

The cryo-electron microscopy structure of human thyroglobulin reveals that proximity, flexibility and solvent exposure are key characteristics of its hormonogenic tyrosine pairs, and provides a framework for understanding the formation of thyroid hormones.

A microorganism that is a proposed relative of our cellular ancestors has been grown successfully in the laboratory. Its internal architecture offers clues to the early evolution of eukaryotic cells.

While bacteria use one FtsZ protein to assemble the cytokinetic Z ring that initiates cell division, many archaea encode two FtsZ proteins. Here, the authors show that while FtsZ1 and FtsZ2 colocalize to form the division ring in Haloferax volcanii, they have different functions in the mechanism of archaeal cell division, with FtsZ1 involved in ring assembly and protein recruitment and FtsZ2 being important for constriction.

Two evolutionarily distant SMC–kleisin complexes are shown to contain a bendable coiled-coil discontinuity near the middle of their arms, which permits a folded conformation with potential implications for DNA loading and translocation.

Bactofilins form cytoskeletal filaments in various bacteria where they mediate, for example, stalk formation and chromosome segregation. This work reports multiple structures of bactofilin filaments that disprove the current filamentation model. Filamentation is shown to be non-polar, and filaments interact with membranes directly through a conserved hydrophobic motif.

Cryo-EM structures of the S. cerevisiae condensin holo complex reveal that ATP binding triggers exchange of the two HEAT-repeat subunits bound to the SMC ATPase head domains, potentially leading to an interconversion of DNA-binding sites in the catalytic core of condensin that might form the basis of its DNA translocation and loop-extrusion activities.

MinC, MinD and MinE proteins form part of an oscillatory network that ensures bacteria divide precisely at their midpoints. Ghosal et al.show that MinC and MinD can form membrane-binding copolymers, and propose a mechanism by which these copolymers may regulate cytokinetic ring assembly.

The plasmid-encoded ParMRC system is one of the best characterized plasmid segregation systems and comprises just three components: an actin-like protein, ParM, a DNA-binding adaptor protein, ParR, and a centromere-like region,parC. Here, the authors review the molecular mechanisms by which the components of this system interact to achieve bipolar DNA segregation.

Water thermodynamics drive changes in macromolecular assembly that rapidly restore intracellular water availability in response to physiological fluctuations in temperature, pressure and osmotic strength.

New high-resolution structures of microtubules reveal that GTP and taxol each stimulate microtubule assembly by inducing straight protofilaments and promoting extension of the interdimer spacing. However, these effects take place through different mechanisms: GTP directly extends loops around the active site, whereas taxol works like a remote lever.

The S-layer structure of C. crescentus is revealed by combining the X-ray crystal structure of an S-layer protein and cryo-ET of cell stalks. The resulting model shows that the S-layer is porous and stabilized by calcium ions.

The structure and function of CetZ, a protein related to both tubulin and FtsZ (the bacterial homologue of tubulin) from the archaeon Haloferax volcanii, is reported and its involvement in the control of cell shape uncovered; it appears that this family of proteins was involved in the control of cell shape long before the evolution of eukaryotes.