Reviews & Analysis

Many organ surfaces are covered by a protective epithelial-cell layer. It emerges that such layers are maintained by cell stretching that triggers cell division mediated by the force-sensitive ion-channel protein Piezo1. See Letter p.118

It emerges that blood-cancer-targeting drugs that block a tumour-survival pathway also activate a mutation-causing enzyme in mice and in human cells. This might have implications for the clinical use of these drugs. See Letter p.489

WIMPs, or weakly interacting massive particles, are the leading candidates for dark matter, the 'missing' mass in the Universe. An experiment has obtained no evidence for such particles, despite an impressive increase in sensitivity.

The ocean's uptake of carbon dioxide increased during the 2000s. Models reveal that this was driven primarily by weak circulation in the upper ocean, solving a mystery of ocean science. See Letter p.215

The existence of medium-sized black holes has long been debated. Such an object has now been discovered in the centre of a dense cluster of stars, potentially enhancing our understanding of all black holes. See Letter p.203

The delicate balance between the immune system and metabolism, and its implications for obesity and metabolic disease are explored.

Technological advances have allowed scientists to sequence the complex quinoa genome. This highlights the ongoing expansion of genomics beyond major crops to other plants that have relevance for global food security. See Article p.307

The enzyme S6K1 phosphorylates the enzyme glutamyl-prolyl tRNA synthetase to modulate metabolic activity and lifespan, revealing an atypical role for this synthetase as a target of a key metabolic signalling pathway. See Letter p.357

One effect of weight-loss surgery is a change in food preferences. An analysis in rats shows that this is caused by altered nutrient signals in the intestine. These activate the vagus nerve to increase signalling in the brain by the neurotransmitter dopamine.

A systematic analysis of bipolar cells, which act as a central signalling conduit in the retina, reveals that the neurons' diverse responses to light are generated largely by feedback from neighbouring amacrine cells. See Article p.439

A theory proposed in 2015 suggested that relatively flat surfaces in mountain ranges were formed by the reorganization of river networks. A fresh analysis rebuts this idea, reigniting discussion of a long-standing problem in Earth science.

The discovery of what is potentially the world's largest continuous tropical peat complex has great implications for global carbon stocks, land management and scientific investment in central Africa. See Letter p.86

The locations of atoms in a metallic alloy nanoparticle have been determined using a combination of electron microscopy and image simulation, revealing links between the particle's structure and magnetic properties. See Letter p.75

Electrical stimulation of the human brain does not enhance memory, according to a report that is in apparent conflict with earlier work. But this discrepancy could enable deeper insight into brain dynamics by stimulating basic research.

An analysis of more than 2,000 species of bird provides insight into how the animals' diverse beak shapes evolved, and points to a single rare event as a trigger for the rapid initial divergence of avian lineages. See Letter p.344

Cellular organelles called peroxisomes aid metabolism, and defective peroxisome formation can cause disease. It emerges that peroxisomes can form de novo from the fusion of vesicles derived from two distinct organelle types. See Letter p.251

Newly discovered microscopic fossils might shed light on the early evolution of the deuterostomes, the animal group that includes vertebrates. But more work is needed to resolve the fossils' place in the deuterostome tree. See Letter p.228

Translation of RNA into proteins is a fundamental process for all cells. Analysis of a mouse model of skin cancer uncovers an atypical RNA-translation program that has a vital role in tumour formation. See Article p.494