Volume 517 Number 7534

Editorials

Science and satire p.243

The terrorist attacks in Paris were an assault on the fundamental values of free and democratic societies. Researchers, and humorists, must combat obscurantism everywhere.

doi: 10.1038/517243a

Out of the bag p.244

The preference for either cats or dogs affects science more than you might think.

doi: 10.1038/517244b

Deep mysteries p.244

Arguments among ocean scientists show how much remains to be discovered.

doi: 10.1038/517244a

News

News Features

State-of-the-art soil p.258

A charcoal-rich product called biochar could boost agricultural yields and control pollution. Scientists are putting the trendy substance to the test.

doi: 10.1038/517258a

Here's looking at you, squid p.262

Margaret McFall-Ngai has dissected the relationship between a beautiful squid and its live-in bacteria — and found lessons for microbiome research on the way.

doi: 10.1038/517262a

News & Views

Boxed up and ready to go p.274

Flow-tank experiments and fluid-dynamics simulations refute the idea that water movements over the body of boxfishes are a stabilizing influence, instead showing that the fish's shape amplifies destabilizing forces to improve manoeuvrability.

doi: 10.1038/517274a

Mixing it up in the mantle p.275

Analysis reveals that the uranium isotopic composition of oceanic crust that is being subducted into Earth's interior is distinctive, allowing the development of chemical heterogeneity in the mantle to be tracked. See Letter p.356

doi: 10.1038/517275a

African dawn p.276

The African Genome Variation Project presents genotyping and whole-genome data from individuals across sub-Saharan Africa, giving insight into population history and guiding future genomic studies on the continent. See Article p.327

doi: 10.1038/nature14077

Hydrophobic interactions in context p.277

The finding that immobilized ions can alter the strength of hydrophobic interactions between molecules suggests a strategy for tuning hydrophobicity to optimize molecular recognition and self-assembly processes. See Letter p.347

doi: 10.1038/517277a

Dragonflies predict and plan their hunts p.279

An analysis reveals that the dragonfly's impressive ability to catch its prey arises from internal calculations about its own movements and those of its target — the first example of such predictions in invertebrates. See Article p.333

doi: 10.1038/nature14078

One catalyst, two reactions p.280

A catalyst has been tuned to make different compounds from the same molecules in carbon–nitrogen bond-forming reactions, depending on the conditions used. The products are potential building blocks for biologically active molecules.

doi: 10.1038/517280a

Seeking ultimate victory p.281

HIV variants that have mutated to escape T-cell immune responses dominate the latent viral reservoir in most patients on antiretroviral therapy. This finding will need to guide therapeutic approaches targeting reactivated virus. See Letter p.381

doi: 10.1038/nature14194

Articles

Internal models direct dragonfly interception steering p.333

This study tracks dragonfly head and body movements during high-velocity and high-precision prey-capture flights, and shows that the dragonfly uses predictive internal models and reactive control to build an interception trajectory that complies with biomechanical constraints.

doi: 10.1038/nature14045

Letters

Impact jetting as the origin of chondrules p.339

The origin of most chondrules (small, previously molten spherules inside meteorites) is shown to be impact jetting; chondrules form from the shock-melted material ejected from a protoplanet on impact, making meteorites a byproduct of planet formation.

doi: 10.1038/nature14105

Modulation of hydrophobic interactions by proximally immobilized ions p.347

Chemical force microscopy measurements show that the immobilization of specific cationic groups near non-polar domains produces pronounced changes in the domains’ hydrophobic interaction strengths: charged ammonium groups double interaction strengths, whereas guanidinium groups eliminate measurable interactions.

doi: 10.1038/nature14018

The terrestrial uranium isotope cycle p.356

Examination of the global uranium cycle — whereby uranium from the Earth’s crust is first transported to the oceans and then returned, by subduction, to the mantle — shows that the subducted uranium is isotopically distinct from the Earth as a whole and that this signature has been stirred throughout upper mantle, arguably within the past 600 million years.

doi: 10.1038/nature14062

Promoterless gene targeting without nucleases ameliorates haemophilia B in mice p.360

Promoterless recombinant adeno-associated virus is used without nucleases to target the human coagulation factor IX gene to the liver-expressed albumin locus in haemophilia B mice, with an on-target integration into ~0.5% of the albumin alleles in hepatocytes; stable F9 plasma levels at 7–20% of normal were obtained, leading to normal coagulation times in treated factor-IX-deficient mice.

doi: 10.1038/nature13864

Long-term phenotypic evolution of bacteria p.369

A comparative analysis of bacterial growth and genetic phenotypes using hundreds of genome-scale metabolic models reveals a two-stage evolutionary process that consists of a rapid initial phenotypic diversification followed by a slow long-term divergence.

doi: 10.1038/nature13827

The neural representation of taste quality at the periphery p.373

Using two-photon microendoscopy and genetically encoded calcium indicators the tuning properties of the first neural station of the gustatory system are explored; results reveal that ganglion neurons are matched to specific taste receptor cells, supporting a labelled line model of information transfer in the taste system.

doi: 10.1038/nature13873

An ERK/Cdk5 axis controls the diabetogenic actions of PPARγ p.391

Obesity-linked insulin resistance is a major precursor to the development of type 2 diabetes. Previous work has shown that phosphorylation of PPARγ (peroxisome proliferator-activated receptor γ) at serine 273 by cyclin-dependent kinase 5 (Cdk5) stimulates diabetogenic gene expression in adipose tissues. Inhibition of this modification is a key therapeutic mechanism for anti-diabetic drugs that bind PPARγ, such as the thiazolidinediones and PPARγ partial agonists or non-agonists. For a better understanding of the importance of this obesity-linked PPARγ phosphorylation, we created mice that ablated Cdk5 specifically in adipose tissues. These mice have both a paradoxical increase in PPARγ phosphorylation at serine 273 and worsened insulin resistance. Unbiased proteomic studies show that extracellular signal-regulated kinase (ERK) kinases are activated in these knockout animals. Here we show that ERK directly phosphorylates serine 273 of PPARγ in a robust manner and that Cdk5 suppresses ERKs through direct action on a novel site in MAP kinase/ERK kinase (MEK). Importantly, pharmacological inhibition of MEK and ERK markedly improves insulin resistance in both obese wild-type and ob/ob mice, and also completely reverses the deleterious effects of the Cdk5 ablation. These data show that an ERK/Cdk5 axis controls PPARγ function and suggest that MEK/ERK inhibitors may hold promise for the treatment of type 2 diabetes.

doi: 10.1038/nature13887