Volume 512 Issue 7514

Editorials

Finding the root p.231

The NIH is right to investigate whether bias makes grant awards unfair.

doi: 10.1038/512231b

What goes up p.231

Federal restrictions on the use of drones by US researchers threaten an increasingly productive tool. The scientific community must speak out while there is a chance to change matters.

doi: 10.1038/512231a

News

Double threat for Tibet p.240

Climate change and human development are jeopardizing the plateau’s fragile environment.

doi: 10.1038/512240a

News Features

Antarctica's secret garden p.244

Samples from a lake hidden under 800 metres of ice contain thousands of microbes and hint at vast ecosystems yet to be discovered.

doi: 10.1038/512244a

News & Views

Microbes eat rock under ice p.256

The first description of the microorganisms inhabiting a subglacial lake deep below the Antarctic ice sheet reveals some of the complex interactive metabolic processes that sustain these microbial communities. See Letter p.310

doi: 10.1038/512256a

It takes muscle to make blood cells p.257

Blood stem cells derive at least in part from an embryonic vessel called the dorsal aorta. It emerges that a flanking tissue called the somite contributes cells and signals to this process. See Letters p.314 & p.319

doi: 10.1038/nature13740

Warning signs of the Iquique earthquake p.258

An earthquake off Chile in 2014 occurred in a region where a great seismic event was expected. Two studies reveal that months of foreshocks and slow slip on the associated plate-boundary fault preceded the event. See Letters p.295 & p.299

doi: 10.1038/nature13655

The time of the last Neanderthals p.260

The application of improved radiocarbon-dating techniques to samples from archaeological sites ranging from Russia to Spain has redefined the timing of the final disappearance of Neanderthals from Europe. See Letter p.306

doi: 10.1038/512260a

Complexity trapped by simplicity p.261

Devices known as magneto-optical traps have long been used to cool and confine atoms, but not molecules — until now. This new ability should enable many studies and applications of the physics of ultracold molecules. See Letter p.286

doi: 10.1038/512261a

Human melting pots in southeast Asia p.262

New genetic methods to analyse mixed human populations have extended existing, multidisciplinary evidence for the historical migrations and mixings of Austronesian peoples.

doi: 10.1038/512262a

Articles

Ribosomal frameshifting in the CCR5 mRNA is regulated by miRNAs and the NMD pathway p.265

Programmed −1 ribosomal frameshifting (−1 PRF) is a process by which a signal in a messenger RNA causes a translating ribosome to shift by one nucleotide, thus changing the reading frame; here −1 PRF in the mRNA for the co-receptor for HIV-1, CCR5, is stimulated by two microRNAs and leads to degradation of the transcript by nonsense-mediated decay and at least one other decay pathway.

doi: 10.1038/nature13429

Crystal structure of a human GABAA receptor p.270

GABAA receptors are the principal mediators of rapid inhibitor synaptic transmission in the brain, and a decline in GABAA signalling leads to diseases including epilepsy, insomnia, anxiety and autism; here, the first X-ray crystal structure of a human GABAA receptor, the human β3 homopentamer, reveals structural features unique for this receptor class and uncovers the locations of key disease-causing mutations.

doi: 10.1038/nature13293

X-ray structure of the mouse serotonin 5-HT3 receptor p.276

The first X-ray crystal structure of the mouse serotonin 5-HT3 receptor, a pentameric ligand-gated ion channel, is similar to those of other Cys-loop receptors — though here electron density for part of the cytoplasmic domain, which is important for trafficking, synaptic localization, and modulation by cytoplasmic proteins, but not visible in previous structures, is also described.

doi: 10.1038/nature13552

Letters

Interacting supernovae from photoionization-confined shells around red supergiant stars p.282

A model in which the stellar wind of the fast-moving red supergiant Betelgeuse is photoionized by radiation from external sources can explain the dense, almost static shell recently discovered around the star, and predicts both that debris from Betelgeuse’s eventual supernova explosion will violently collide with the shell and that other red supergiants should have similar, but much more massive, shells.

doi: 10.1038/nature13522

Magneto-optical trapping of a diatomic molecule p.286

Magneto-optical trapping is the standard method for laser cooling and confinement of atomic gases but now this technique has been demonstrated for the diatomic molecule strontium monofluoride, leading to the lowest temperature yet achieved by cooling a molecular gas.

doi: 10.1038/nature13634

A microbial ecosystem beneath the West Antarctic ice sheet p.310

There has been active debate over microbial life in Antarctic subglacial lakes owing to a paucity of direct observations from beneath the ice sheet and concerns about contamination in the samples that do exist; here the authors present the first geomicrobiological description of pristine water and surficial sediments from Subglacial Lake Whillans, and show that the lake water contains a diverse microbial community, many members of which are closely related to chemolithoautotrophic bacteria and archaea.

doi: 10.1038/nature13667

Jam1a–Jam2a interactions regulate haematopoietic stem cell fate through Notch signalling p.319

Notch signalling has a key role in the generation of haematopoietic stem cells (HSCs) during vertebrate development; here two adhesion molecules, Jam1a and Jam2a, are shown to be essential for the contact between precursors of HSCs and the somite during embryonic migration, and the Jam1a–Jam2a interaction is shown to be needed to transmit the Notch signal and produce HSCs.

doi: 10.1038/nature13623

A vaccine targeting mutant IDH1 induces antitumour immunity p.324

The mutant IDH1 protein, which is expressed in a large fraction of human gliomas, is shown to be immunogenic; mutant-specific immune responses can be detected in patients with IDH1 mutated gliomas and generated in mice and are shown to treat established IDH1 mutant tumours in a syngeneic MHC humanized mouse model in a CD4 T-cell-dependent manner.

doi: 10.1038/nature13387

Dynamic pathways of −1 translational frameshifting p.328

To investigate the mechanism of frameshifting during messenger RNA translation, a technique was developed to monitor translation of single molecules in real time using Förster resonance energy transfer (FRET); ribosomes were revealed to pause tenfold longer than usual during elongation at the frameshifting sites.

doi: 10.1038/nature13428

X-ray structures of GluCl in apo states reveal a gating mechanism of Cys-loop receptors p.333

This study solved structures of the glutamate-gated chloride channel (GluCl), a Cys-loop receptor from C. elegant, in an apo, closed state and in a lipid-bound state — comparison of these structures with a previously published structure of GluCl in an ivermectin-bound state reveals what conformational changes probably occur as this membrane protein transitions from the closed/resting state towards an open/activated state.

doi: 10.1038/nature13669