Reviews & Analysis

Techniques for isolating and analysing leaf cell types have now been developed, leading to the discovery that circadian clocks in the plant vasculature communicate with and regulate clocks in neighbouring cells. See Letter p.419

The sequences of two sponge genomes provide evidence that the ParaHox developmental genes are older than previously thought. This has implications for animal taxonomy and for developmental and evolutionary biology. See Letter p.620

The structure of an enzyme that is bound to a nucleosome — a protein complex around which DNA is wrapped — reveals how contacts between the two orient the enzyme so that it can modify a specific amino-acid residue. See Article p.591

An RNA enzyme has been generated that can assemble a mirror-image version of itself. The finding helps to answer a long-standing conundrum about how RNA molecules could have proliferated on prebiotic Earth. See Letter p.440

Engineering complex tissues requires high-throughput, three-dimensional patterning of materials and cells. A method to assemble small gel components using magnetic forces from encapsulated free radicals could be just the ticket.

A pair of newly discovered 70-million-year-old fossils from Mongolia — including material previously lost to poaching — reveals the true nature of one of the most enigmatic dinosaur species, Deinocheirus mirificus. See Letter p.257

Astronomers have suspected for some time that magnetic fields are a key ingredient in the accretion of material that surrounds young stars. New observations have just begun to reveal these fields in action. See Letter p.597

An analysis of hundreds of star-grazing comets in a young planetary system shows that they form two families: a group of old, dried-out comets and a younger group probably related to the break-up of a larger planetary body. See Letter p.462

During inflammation, lymph nodes swell with an influx of immune cells. New findings identify a signalling pathway that induces relaxation in the contractile cells that give structure to these organs. See Letter p.498

Blocking the activity of macrophages may delay the spread of cancer. But new findings show that these immune cells can rapidly rebound to tumours after therapy withdrawal, accelerating lethal metastasis in mice. See Letter p.130

Gradients of fibroblast growth factors often induce cells to adopt different fates. A study in zebrafish embryos reveals another, unexpected role when the factors are trapped in small spaces by a special arrangement of cells. See Letter p.120

In a finding that highlights ways to optimize the efficacy of antibody-based therapeutics and vaccines, the activity of potent HIV-1-neutralizing antibodies has been confirmed to depend on cellular binding to the antibodies' Fc regions.

Fibroblast cells are known as key players in the repair of damaged heart structures. New findings show that injury also induces fibroblasts to become endothelial cells, helping to mend damaged blood vessels. See Article p.585

Observations of two faint galaxies with a low abundance of elements heavier than helium show that the galaxies have an efficiency of star formation less than one-tenth of that of the Milky Way and similar galaxies. See Letter p.335

Integrated assessment models show that, without new climate policies, abundant supplies of natural gas will have little impact on greenhouse-gas emissions and climate change. See Letter p.482

Evolutionary and ecosystem processes have long been treated as distinct. The finding that interactions among plant species cause rapid evolutionary changes that affect ecosystem function suggests that it is time for unification. See Letter p.108