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Ripple effects of New Zealand earthquake continue to this day

Nature - Mon, 04/24/2017 - 00:00

Ripple effects of New Zealand earthquake continue to this day

Nature 544, 7651 (2017). http://www.nature.com/doifinder/10.1038/nature.2017.21876

Author: Alexandra Witze

November tremor sparked slow, deep movements in Earth’s crust that increase the chances of a similar severe quake within a year.

Categories: Literature

More surgeons must start doing basic science

Nature - Fri, 04/21/2017 - 00:00

More surgeons must start doing basic science

Nature 544, 7651 (2017). doi:10.1038/544393b

They say they don't have the time or incentives to do research — and that’s dangerous for translational medicine.

Categories: Literature

What happened at March for Science events around the world

Nature - Fri, 04/21/2017 - 00:00

What happened at March for Science events around the world

Nature 544, 7651 (2017). http://www.nature.com/doifinder/10.1038/nature.2017.21853

Authors: Sara Reardon, Nicky Phillips, Alison Abbott, Barbara Casassus, Ewen Callaway, Alexandra Witze, Corie Lok & Emiliano Rodriguez Mega

Nature reported from marches in cities including Sydney, Washington DC and Paris, as people took to the streets in support of science.

Categories: Literature

Mining threatens Chinese fossil site that revealed planet's earliest animals

Nature - Thu, 04/20/2017 - 00:00

Mining threatens Chinese fossil site that revealed planet's earliest animals

Nature 544, 7651 (2017). http://www.nature.com/doifinder/10.1038/nature.2017.21869

Author: David Cyranoski

Protests sparked by the destruction of three key fossil-hunting areas result in a temporary halt of phosphate mining.

Categories: Literature

Animal behaviour: How to build a better dad

Nature - Wed, 04/19/2017 - 00:00

Animal behaviour: How to build a better dad

Nature 544, 7651 (2017). doi:10.1038/nature22486

Authors: Steven M. Phelps

Oldfield mice and deer mice differ in their parental care, most dramatically in the behaviour of fathers. A study reveals the genetic and neuronal contributions to variation in parental care. See Article p.434

Categories: Literature

The genetic basis of parental care evolution in monogamous mice

Nature - Wed, 04/19/2017 - 00:00

The genetic basis of parental care evolution in monogamous mice

Nature 544, 7651 (2017). doi:10.1038/nature22074

Authors: Andres Bendesky, Young-Mi Kwon, Jean-Marc Lassance, Caitlin L. Lewarch, Shenqin Yao, Brant K. Peterson, Meng Xiao He, Catherine Dulac & Hopi E. Hoekstra

Parental care is essential for the survival of mammals, yet the mechanisms underlying its evolution remain largely unknown. Here we show that two sister species of mice, Peromyscus polionotus and Peromyscus maniculatus, have large and heritable differences in parental behaviour. Using quantitative genetics,

Categories: Literature

Mechanism of chromatin remodelling revealed by the Snf2-nucleosome structure

Nature - Wed, 04/19/2017 - 00:00

Mechanism of chromatin remodelling revealed by the Snf2-nucleosome structure

Nature 544, 7651 (2017). doi:10.1038/nature22036

Authors: Xiaoyu Liu, Meijing Li, Xian Xia, Xueming Li & Zhucheng Chen

Chromatin remodellers are helicase-like, ATP-dependent enzymes that alter chromatin structure and nucleosome positions to allow regulatory proteins access to DNA. Here we report the cryo-electron microscopy structure of chromatin remodeller Switch/sucrose non-fermentable (SWI2/SNF2) from Saccharomyces cerevisiae bound to the nucleosome. The structure shows that

Categories: Literature

Structure and allosteric inhibition of excitatory amino acid transporter 1

Nature - Wed, 04/19/2017 - 00:00

Structure and allosteric inhibition of excitatory amino acid transporter 1

Nature 544, 7651 (2017). doi:10.1038/nature22064

Authors: Juan C. Canul-Tec, Reda Assal, Erica Cirri, Pierre Legrand, Sébastien Brier, Julia Chamot-Rooke & Nicolas Reyes

Human members of the solute carrier 1 (SLC1) family of transporters take up excitatory neurotransmitters in the brain and amino acids in peripheral organs. Dysregulation of the function of SLC1 transporters is associated with neurodegenerative disorders and cancer. Here we present crystal structures of a

Categories: Literature

Super-multiplex vibrational imaging

Nature - Wed, 04/19/2017 - 00:00

Super-multiplex vibrational imaging

Nature 544, 7651 (2017). doi:10.1038/nature22051

Authors: Lu Wei, Zhixing Chen, Lixue Shi, Rong Long, Andrew V. Anzalone, Luyuan Zhang, Fanghao Hu, Rafael Yuste, Virginia W. Cornish & Wei Min

The ability to visualize directly a large number of distinct molecular species inside cells is increasingly essential for understanding complex systems and processes. Even though existing methods have successfully been used to explore structure–function relationships in nervous systems, to profile RNA in situ, to reveal the heterogeneity of tumour microenvironments and to study dynamic macromolecular assembly, it remains challenging to image many species with high selectivity and sensitivity under biological conditions. For instance, fluorescence microscopy faces a ‘colour barrier’, owing to the intrinsically broad (about 1,500 inverse centimetres) and featureless nature of fluorescence spectra that limits the number of resolvable colours to two to five (or seven to nine if using complicated instrumentation and analysis). Spontaneous Raman microscopy probes vibrational transitions with much narrower resonances (peak width of about 10 inverse centimetres) and so does not suffer from this problem, but weak signals make many bio-imaging applications impossible. Although surface-enhanced Raman scattering offers high sensitivity and multiplicity, it cannot be readily used to image specific molecular targets quantitatively inside live cells. Here we use stimulated Raman scattering under electronic pre-resonance conditions to image target molecules inside living cells with very high vibrational selectivity and sensitivity (down to 250 nanomolar with a time constant of 1 millisecond). We create a palette of triple-bond-conjugated near-infrared dyes that each displays a single peak in the cell-silent Raman spectral window; when combined with available fluorescent probes, this palette provides 24 resolvable colours, with the potential for further expansion. Proof-of-principle experiments on neuronal co-cultures and brain tissues reveal cell-type-dependent heterogeneities in DNA and protein metabolism under physiological and pathological conditions, underscoring the potential of this 24-colour (super-multiplex) optical imaging approach for elucidating intricate interactions in complex biological systems.

Categories: Literature

Human umbilical cord plasma proteins revitalize hippocampal function in aged mice

Nature - Wed, 04/19/2017 - 00:00

Human umbilical cord plasma proteins revitalize hippocampal function in aged mice

Nature 544, 7651 (2017). doi:10.1038/nature22067

Authors: Joseph M. Castellano, Kira I. Mosher, Rachelle J. Abbey, Alisha A. McBride, Michelle L. James, Daniela Berdnik, Jadon C. Shen, Bende Zou, Xinmin S. Xie, Martha Tingle, Izumi V. Hinkson, Martin S. Angst & Tony Wyss-Coray

Ageing drives changes in neuronal and cognitive function, the decline of which is a major feature of many neurological disorders. The hippocampus, a brain region subserving roles of spatial and episodic memory and learning, is sensitive to the detrimental effects of ageing at morphological and molecular levels. With advancing age, synapses in various hippocampal subfields exhibit impaired long-term potentiation, an electrophysiological correlate of learning and memory. At the molecular level, immediate early genes are among the synaptic plasticity genes that are both induced by long-term potentiation and downregulated in the aged brain. In addition to revitalizing other aged tissues, exposure to factors in young blood counteracts age-related changes in these central nervous system parameters, although the identities of specific cognition-promoting factors or whether such activity exists in human plasma remains unknown. We hypothesized that plasma of an early developmental stage, namely umbilical cord plasma, provides a reservoir of such plasticity-promoting proteins. Here we show that human cord plasma treatment revitalizes the hippocampus and improves cognitive function in aged mice. Tissue inhibitor of metalloproteinases 2 (TIMP2), a blood-borne factor enriched in human cord plasma, young mouse plasma, and young mouse hippocampi, appears in the brain after systemic administration and increases synaptic plasticity and hippocampal-dependent cognition in aged mice. Depletion experiments in aged mice revealed TIMP2 to be necessary for the cognitive benefits conferred by cord plasma. We find that systemic pools of TIMP2 are necessary for spatial memory in young mice, while treatment of brain slices with TIMP2 antibody prevents long-term potentiation, arguing for previously unknown roles for TIMP2 in normal hippocampal function. Our findings reveal that human cord plasma contains plasticity-enhancing proteins of high translational value for targeting ageing- or disease-associated hippocampal dysfunction.

Categories: Literature

SLAMF7 is critical for phagocytosis of haematopoietic tumour cells via Mac-1 integrin

Nature - Wed, 04/19/2017 - 00:00

SLAMF7 is critical for phagocytosis of haematopoietic tumour cells via Mac-1 integrin

Nature 544, 7651 (2017). doi:10.1038/nature22076

Authors: Jun Chen, Ming-Chao Zhong, Huaijian Guo, Dominique Davidson, Sabrin Mishel, Yan Lu, Inmoo Rhee, Luis-Alberto Pérez-Quintero, Shaohua Zhang, Mario-Ernesto Cruz-Munoz, Ning Wu, Donald C. Vinh, Meenal Sinha, Virginie Calderon, Clifford A. Lowell, Jayne S. Danska & André Veillette

Cancer cells elude anti-tumour immunity through multiple mechanisms, including upregulated expression of ligands for inhibitory immune checkpoint receptors. Phagocytosis by macrophages plays a critical role in cancer control. Therapeutic blockade of signal regulatory protein (SIRP)-α, an inhibitory receptor on macrophages, or of its ligand CD47 expressed on tumour cells, improves tumour cell elimination in vitro and in vivo, suggesting that blockade of the SIRPα–CD47 checkpoint could be useful in treating human cancer. However, the pro-phagocytic receptor(s) responsible for tumour cell phagocytosis is(are) largely unknown. Here we find that macrophages are much more efficient at phagocytosis of haematopoietic tumour cells, compared with non-haematopoietic tumour cells, in response to SIRPα–CD47 blockade. Using a mouse lacking the signalling lymphocytic activation molecule (SLAM) family of homotypic haematopoietic cell-specific receptors, we determined that phagocytosis of haematopoietic tumour cells during SIRPα–CD47 blockade was strictly dependent on SLAM family receptors in vitro and in vivo. In both mouse and human cells, this function required a single SLAM family member, SLAMF7 (also known as CRACC, CS1, CD319), expressed on macrophages and tumour cell targets. In contrast to most SLAM receptor functions, SLAMF7-mediated phagocytosis was independent of signalling lymphocyte activation molecule-associated protein (SAP) adaptors. Instead, it depended on the ability of SLAMF7 to interact with integrin Mac-1 (refs 18, 19, 20) and utilize signals involving immunoreceptor tyrosine-based activation motifs. These findings elucidate the mechanism by which macrophages engulf and destroy haematopoietic tumour cells. They also reveal a novel SAP adaptor-independent function for a SLAM receptor. Lastly, they suggest that patients with tumours expressing SLAMF7 are more likely to respond to SIRPα–CD47 blockade therapy.

Categories: Literature

Cohesin is positioned in mammalian genomes by transcription, CTCF and Wapl

Nature - Wed, 04/19/2017 - 00:00

Cohesin is positioned in mammalian genomes by transcription, CTCF and Wapl

Nature 544, 7651 (2017). doi:10.1038/nature22063

Authors: Georg A. Busslinger, Roman R. Stocsits, Petra van der Lelij, Elin Axelsson, Antonio Tedeschi, Niels Galjart & Jan-Michael Peters

Mammalian genomes are spatially organized by CCCTC-binding factor (CTCF) and cohesin into chromatin loops and topologically associated domains, which have important roles in gene regulation and recombination. By binding to specific sequences, CTCF defines contact points for cohesin-mediated long-range chromosomal cis-interactions. Cohesin is also present at these sites, but has been proposed to be loaded onto DNA elsewhere and to extrude chromatin loops until it encounters CTCF bound to DNA. How cohesin is recruited to CTCF sites, according to this or other models, is unknown. Here we show that the distribution of cohesin in the mouse genome depends on transcription, CTCF and the cohesin release factor Wings apart-like (Wapl). In CTCF-depleted fibroblasts, cohesin cannot be properly recruited to CTCF sites but instead accumulates at transcription start sites of active genes, where the cohesin-loading complex is located. In the absence of both CTCF and Wapl, cohesin accumulates in up to 70 kilobase-long regions at 3′-ends of active genes, in particular if these converge on each other. Changing gene expression modulates the position of these ‘cohesin islands’. These findings indicate that transcription can relocate mammalian cohesin over long distances on DNA, as previously reported for yeast cohesin, that this translocation contributes to positioning cohesin at CTCF sites, and that active genes can be freed from cohesin either by transcription-mediated translocation or by Wapl-mediated release.

Categories: Literature

Fake-drug crackdown, tackling misconduct and Europa’s plumes

Nature - Wed, 04/19/2017 - 00:00

Fake-drug crackdown, tackling misconduct and Europa’s plumes

Nature 544, 7650 (2017). http://www.nature.com/doifinder/10.1038/544274a

The week in science: 14–20 April 2017.

Categories: Literature

Drivers gear up for world’s first nanocar race

Nature - Wed, 04/19/2017 - 00:00

Drivers gear up for world’s first nanocar race

Nature 544, 7650 (2017). http://www.nature.com/doifinder/10.1038/544278a

Author: Davide Castelvecchi

Chemists will navigate molecular wagons along a tiny golden track.

Categories: Literature

Five hacks for digital democracy

Nature - Wed, 04/19/2017 - 00:00

Five hacks for digital democracy

Nature 544, 7650 (2017). doi:10.1038/544287a

Author: Beth Simone Noveck

Beth Simone Noveck urges researchers to work out how technology can improve public institutions.

Categories: Literature

Human behaviour: Guns and roses

Nature - Wed, 04/19/2017 - 00:00

Human behaviour: Guns and roses

Nature 544, 7650 (2017). doi:10.1038/544294a

Author: Anne Harrington

Anne Harrington savours Robert Sapolsky's tome on humanity's vacillations.

Categories: Literature

Books in brief

Nature - Wed, 04/19/2017 - 00:00

Books in brief

Nature 544, 7650 (2017). doi:10.1038/544295a

Author: Barbara Kiser

Barbara Kiser reviews five of the week's best science picks.

Categories: Literature

Perception: Our useful inability to see reality

Nature - Wed, 04/19/2017 - 00:00

Perception: Our useful inability to see reality

Nature 544, 7650 (2017). doi:10.1038/544296a

Author: Douwe Draaisma

There's some deviant thinking behind perception, discovers Douwe Draaisma.

Categories: Literature

Marine litter: Sea change for plastic pollution

Nature - Wed, 04/19/2017 - 00:00

Marine litter: Sea change for plastic pollution

Nature 544, 7650 (2017). doi:10.1038/544297a

Authors: Melanie Bergmann, Mine B. Tekman & Lars Gutow

Scientists, policymakers and the public can learn from LITTERBASE, a newly launched online database of information from 1,300 peer-reviewed publications that provides analysis and visualization of human-generated marine litter worldwide (http://litterbase.org).This comprehensive resource will help to coordinate international action against a lethal form

Categories: Literature

Carbon markets: extend, don't limit

Nature - Wed, 04/19/2017 - 00:00

Carbon markets: extend, don't limit

Nature 544, 7650 (2017). doi:10.1038/544297b

Authors: Nathaniel Keohane & Erica Morehouse

In our view, your headline 'Don't link carbon markets' is poor advice to policymakers (J.GreenNature543, 484–486;10.1038/543484a2017). To cut carbon pollution at the pace and scale that science demands, we must create linkages that can

Categories: Literature

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