Editorials
Hurricane Harvey highlights the struggle to apply climate science.
doi: 10.1038/548499b
The Trump administration has stepped up its assault on environmental protections by halting a US$1-million study on the health risks of coal mining — casting a pall on academic freedom.
doi: 10.1038/548499a
News
High-speed shooter will help scientists to make molecular movies.
doi: 10.1038/548507a
Australian lawsuit highlights how difficult it is to turn global warming data into useful advice.
doi: 10.1038/548508a
Energy researcher Daniel Kammen faults US president’s positions on climate change and energy and his failure to condemn white supremacists.
doi: 10.1038/nature.2017.22510
The animals seem to have died while huddling together 70 million years ago.
doi: 10.1038/nature.2017.22508
Blast from Hunley’s own torpedo probably killed its crew instantly.
doi: 10.1038/nature.2017.22447
News Features
As the mission speeds towards its conclusion, Nature takes a look at what researchers have learnt about the planet’s moons, rings and tempest-filled skies.
doi: 10.1038/548512a
News & Views
Binary star systems known as cataclysmic variables can exhibit violent explosions called novae. Observations of a system hundreds of years after a nova reveal details about the long-term effects of such explosions. See Letter p.558
doi: 10.1038/548526a
Bacteria and archaea use an innate immune system called CRISPR–Cas to combat viral infection. The identification of a family of molecules that play a key part in this system deepens our understanding of such immunity. See Article p.543
doi: 10.1038/nature23532
A revised timeline for when algae became ecologically important among plankton in the ancient oceans reveals a link between chemical changes in those waters and the emergence of animals in marine ecosystems. See Letter p.578
doi: 10.1038/nature23539
Molecules that block the activity or production of the protein ANGPTL3 have now been found to lower blood levels of lipoproteins and cholesterol in mice and healthy humans, mimicking the protective effects of genetic mutations in ANGPTL3.
doi: 10.1038/nature23544
A study confirms that volcanism set off one of Earth's fastest global-warming events. But the release of greenhouse gases was slow enough for negative feedbacks to mitigate impacts such as ocean acidification. See Letter p.573
doi: 10.1038/548531a
Formaldehyde, a DNA-damaging agent formed in cells, has now been shown to support metabolic processes that involve molecular units containing a single carbon atom — linking metabolism to a DNA-protection mechanism. See Article p.549
doi: 10.1038/nature23541
The discovery of the inflammasome protein complex in 2002 was a breakthrough in our understanding of how the immune system triggers inflammation. Now researchers are attempting to modulate its activity to treat disease.
doi: 10.1038/548534a
Articles
The authors describe a two-cell-type CRISPR screen to identify tumour-intrinsic genes that regulate the sensitivity of cancer cells to effector T cell function.
doi: 10.1038/nature23477
CRISPR-associated protein Csm6 is activated by a cyclic oligoadenylate second messenger generated by Cas10 activity in the CRISPR type III interference complex, representing a novel mechanism of CRISPR interference.
doi: 10.1038/nature23467
The mechanism by which formaldehyde, a potent DNA and protein crosslinking agent, is generated from folate is described, with implications for the treatment of certain cancers.
doi: 10.1038/nature23481
Letters
Estimates of parameters of strong gravitational lenses are obtained in an automated way using convolutional neural networks, with similar accuracy and greatly improved speed compared to previous methods.
doi: 10.1038/nature23463
‘Cataclysmic variables’ are binary star systems in which one star of the pair is a white dwarf, and which often generate bright and energetic stellar outbursts. Classical novae are one type of outburst: when the white dwarf accretes enough matter from its companion, the resulting hydrogen-rich atmospheric envelope can host a runaway thermonuclear reaction that generates a rapid brightening. Achieving peak luminosities of up to one million times that of the Sun, all classical novae are recurrent, on timescales of months to millennia. During the century before and after an eruption, the ‘novalike’ binary systems that give rise to classical novae exhibit high rates of mass transfer to their white dwarfs. Another type of outburst is the dwarf nova: these occur in binaries that have stellar masses and periods indistinguishable from those of novalikes but much lower mass-transfer rates, when accretion-disk instabilities drop matter onto the white dwarfs. The co-existence at the same orbital period of novalike binaries and dwarf novae—which are identical but for their widely varying accretion rates—has been a longstanding puzzle. Here we report the recovery of the binary star underlying the classical nova eruption of 11 March AD 1437 (refs 12, 13), and independently confirm its age by proper-motion dating. We show that, almost 500 years after a classical-nova event, the system exhibited dwarf-nova eruptions. The three other oldest recovered classical novae display nova shells, but lack firm post-eruption ages, and are also dwarf novae at present. We conclude that many old novae become dwarf novae for part of the millennia between successive nova eruptions.
doi: 10.1038/nature23644
Antiskyrmions, in which the magnetization rotates both as a transverse helix and as a cycloid, are found in acentric tetragonal Heusler compounds over a wide range of temperatures.
doi: 10.1038/nature23466
Rotary molecular machines, activated by ultraviolet light, are able to perturb and drill into cell membranes in a controllable manner, and more efficiently than those exhibiting flip-flopping or random motion.
doi: 10.1038/nature23657
The Palaeocene–Eocene Thermal Maximum (PETM) was a global warming event that occurred about 56 million years ago, and is commonly thought to have been driven primarily by the destabilization of carbon from surface sedimentary reservoirs such as methane hydrates. However, it remains controversial whether such reservoirs were indeed the source of the carbon that drove the warming. Resolving this issue is key to understanding the proximal cause of the warming, and to quantifying the roles of triggers versus feedbacks. Here we present boron isotope data—a proxy for seawater pH—that show that the ocean surface pH was persistently low during the PETM. We combine our pH data with a paired carbon isotope record in an Earth system model in order to reconstruct the unfolding carbon-cycle dynamics during the event. We find strong evidence for a much larger (more than 10,000 petagrams)—and, on average, isotopically heavier—carbon source than considered previously. This leads us to identify volcanism associated with the North Atlantic Igneous Province, rather than carbon from a surface reservoir, as the main driver of the PETM. This finding implies that climate-driven amplification of organic carbon feedbacks probably played only a minor part in driving the event. However, we find that enhanced burial of organic matter seems to have been important in eventually sequestering the released carbon and accelerating the recovery of the Earth system.
doi: 10.1038/nature23646
Steroid biomarkers provide evidence for a rapid rise of marine planktonic algae between 659 and 645 million years ago, establishing more efficient energy transfers and driving ecosystems towards larger and increasingly complex organisms.
doi: 10.1038/nature23457
GABAergic Lhx6+ neurons in the ventral zona incerta promote both rapid eye movement and non-rapid eye movement sleep and inhibit the activity of wake-promoting GABAergic and Hcrt+ neurons of the lateral hypothalamus.
doi: 10.1038/nature23663
Steady-state turnover of the Drosophila midgut arises through an intercellular, E-cadherin–EGFR relay that couples the death of individual enterocytes to the divisions of nearby stem cells.
doi: 10.1038/nature23678
In a preclinical study, dopaminergic neurons derived from human induced pluripotent stem cells were implanted into a primate model of Parkinson’s disease, where they were found to exhibit long-term survival, function as mid-brain dopaminergic neurons, and increase spontaneous movements.
doi: 10.1038/nature23664
Up to 10% of individuals in malaria-endemic regions produce antibodies that react to malaria antigens through an additional LAIR1 domain that is inserted by two different insertion modalities.
doi: 10.1038/nature23670
The tumour suppressor liver kinase B1 (LKB1) regulates the metabolic and functional fitness of regulatory T cells in the control of immune tolerance and homeostasis.
doi: 10.1038/nature23665
A high-throughput approach using a DNA-barcoded nucleosome library shows that ISWI chromatin remodellers can distinguish between differently modified nucleosomes.
doi: 10.1038/nature23671