Phase separation participates in biological processes as a fundamental mechanism for assembling subcellular structures and provides new perspectives for basic study and therapeutic applications. The cover depicts drops of dew condensing on a leaf, symbolizing condensates formed via phase separation in cells.

See Jingjing Xie et al.

Small-molecule targeting of particular KRAS mutations offer promise for cancer therapy. The cover depicts a small-molecule ligand (red) inhibiting the oncogenic mutant protein K-Ras(G12S) (cyan) by forming a covalent ester adduct at the mutant serine.

See Zhang et al.

Local generation of NTPs (LAGOON) enables the precise spatiotemporal control of NTP availability via uncaging of NTPs using a UV laser. The cover image depicts a single-molecule FRET assay controlled by LAGOON, in which a double-stranded DNA molecule is unwound by a T4 helicase after binding of ATP.

See Sabantsev et al.

Myelin membranes wrap around axons to support neural health. The cover image depicts an oligodendrocyte (shown in purple), the specialized glial cell that produces central nervous system myelin. Enhancing myelin repair, or ‘remyelination’, remains an attractive therapeutic approach for replacing lost oligodendrocytes in diseases such as multiple sclerosis.

See Caprariello & Adams

Photocatalytic cell tagging (PhoTag) enables the selective introduction of chemical tags within cell–cell contact interfaces via visible light activation of localized flavin photocatalysts. The cover image depicts immune synapses selectively and covalently tagged with biotin tyramide through PhoTag technology.

See Oslund et al.

GPX4 is a selenocysteine-containing protein that functions as the main cellular defense against ferroptosis. The cover image shows that decreased uptake of selenium into cancer cells results in ribosome stalling and collisions during the translation of GPX4, which leads to decreased levels of GPX4.

See Li et al.

Coral reefs are biodiversity hotspots, and chemical defenses are often essential for survival against competition. Octocorals are abundant in these environments, where they biosynthesize terpenoids for protection. Here, an assemblage of octocoral colonies can be seen dominating the microenvironment along a rock wall off the coast of Fiji, demonstrating this fierce ecological competition.

See Scesa et al., Burkhardt et al. & Nguyen et al.

Much like passengers in a public transit system, cells rely on the highly regulated flow of metabolites through many overlapping, intersecting and competing pathways to keep systems running smoothly. This special issue features pieces that explore the tools used to study metabolic processes, what happens when these processes go off the tracks, and how cells (and scientists) can address this.

ROSALIND (‘RNA outputs activated by ligand induction’) is an RNA-based cell-free biosensor platform whose performance is enhanced by the integration of toehold-mediated DNA strand displacement. The image is a portrait of Rosalind Franklin generated by ROSALIND to memorialize her discoveries that enable the ROSALIND reactions.

See Jung et al.

Endogenous chemokine CCL15 interacts with its receptor CCR1 for G-protein signaling activation, whereas its N-terminal truncations act differently via allosteric activation of β-arrestin. The image shows the structures of CCR1 bound with CCL15 truncations, and the critical amino acid of CCR1 is highlighted.

See Shao et al.

Shown is a zebrafish embryo expressing a fluorescent fusion of the optogenetic protein BcLOV4, whose activity responds not only to light but also to temperature. BcLOV4 localizes to the plasma membrane in response to blue light, but its membrane association subsequently decays at a rate that depends on temperature.

See Benman et al.

Shown is the tropical greenhouse of the Matthaei Botanical Gardens. Plants from botanical collections at the University of Michigan have been used for the bioinformatic discovery of plant peptides with new side-chain macrocyclizations derived from a copper-dependent autocatalytic peptide cyclase called the BURP domain.

See Chigumba et al.