Visualization of cellular dynamics during pancreatic endocrinogenesis based on RNA velocity analysis. Bergen et al. present scVelo, a method that improves RNA velocity analysis by capturing transient cell states and providing a more detailed view of cellular transcriptional dynamics.

See Bergen et al.

A study in this issue of Nature Biotechnology reports the use of bioengineered scaffolds to repair injured uteri and enable live births in rabbits. This image shows one of the subjects, a New Zealand white, with her kit.

See Magalhaes et al.

In this issue, several groups report their findings on the development of methods to detect SARS-CoV-2 in patients and in the community, and benchmark assays to detect SARS-CoV-2-specific antibodies.

See Nachtigall et al., Peccia et al. and Whitman et al.

Zhenan Bao and colleagues design and fabricate multilayered electronics that adapt to growing nerves, allowing chronic electrical stimulation during the fastest growth period in rats. The approach opens the door to electronic medicine that adapts to growth in children and adolescents.

See Y. Liu et al.

A scanning electron micrograph of a macrophage (top) and cancer cells. In this issue, Klichinsky et al. engineer macrophages with human chimeric antigen receptors, directing their phagocytic activity against tumors.

See Klichinsky et al.

CRISPR-based genome editing has become a mainstay of experimental biology and is now maturing into a tool for therapeutic applications. Constant progress is being made in designing ever more sophisticated protein machines to catalyze desired changes with high efficiency and specificity, and in the methods to deliver the macromolecules involved to the tissues and cells. Many of the more recent advances have not entered clinical development yet, but will ultimately help therapeutic genome editing fulfill its full potential. Illustration of the structure of the CRISPR–Cas9 gene-editing complex, showing the guide RNA template (red), the Cas9 protein (blue) and the double strand of DNA (gray).

See Focus on CRISPR tools and therapies

Optimizing guide RNA design for Cas13. With data from massively parallel screens, Wessels et al. develop computational models to identify optimal guide RNAs for the RNA-targeting CRISPR enzyme Cas13d.

See Wessels et al.

An adult western corn rootworm, one of the most devastating pests of maize. Machado et al. use experimental evolution of bacterial symbionts of a nematode pathogen of western corn rootworm larvae to improve the insect-killing efficacy of their nematode host.

See Machado et al.

Aedes aegytpi mosquitoes are imaged in a sex-sorting device. Crawford et al. describe the production of accurately sorted sterile male mosquitoes and their deployment in a mosquito-eradication trial.

See Crawford et al.

Precise loading of diverse peptides for vaccination is enabled by a strategy for peptide–TLR7/8 conjugate self-assembly of uniform nanoparticles. The approach is compatible with the development of personalized strategies, such as cancer vaccines targeting patient-specific neoepitopes.

See Lynn et al.

Compact, early-fruiting ‘triple-determinate’ tomato and groundcherry plants suitable for vertical farming are produced using genome editing.

See Kwon et al.

Developmental regulators are used to reprogram edited dicot plant cells into meristematic cells that grow into plants without tissue culture.

See Maher et al.