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Structural biology: Pain-sensing TRPA1 channel resolved

Nature - Wed, 04/08/2015 - 00:00

Structural biology: Pain-sensing TRPA1 channel resolved

Nature 520, 7548 (2015). doi:10.1038/nature14383

Authors: David E. Clapham

The TRPA1 ion channel activates pain pathways in response to noxious compounds. The structure of TRPA1 has now been solved, providing insight into how it functions. See Article p.511

Categories: Literature

Structure of the TRPA1 ion channel suggests regulatory mechanisms

Nature - Wed, 04/08/2015 - 00:00

Structure of the TRPA1 ion channel suggests regulatory mechanisms

Nature 520, 7548 (2015). doi:10.1038/nature14367

Authors: Candice E. Paulsen, Jean-Paul Armache, Yuan Gao, Yifan Cheng & David Julius

The TRPA1 ion channel (also known as the wasabi receptor) is a detector of noxious chemical agents encountered in our environment or produced endogenously during tissue injury or drug metabolism. These include a broad class of electrophiles that activate the channel through covalent protein modification.

Categories: Literature

Tungsten isotopic evidence for disproportional late accretion to the Earth and Moon

Nature - Wed, 04/08/2015 - 00:00

Tungsten isotopic evidence for disproportional late accretion to the Earth and Moon

Nature 520, 7548 (2015). doi:10.1038/nature14355

Authors: Mathieu Touboul, Igor S. Puchtel & Richard J. Walker

Characterization of the hafnium–tungsten systematics (182Hf decaying to 182W and emitting two electrons with a half-life of 8.9 million years) of the lunar mantle will enable better constraints on the timescale and processes involved in the currently accepted giant-impact theory for the formation and evolution of the Moon, and for testing the late-accretion hypothesis. Uniform, terrestrial-mantle-like W isotopic compositions have been reported among crystallization products of the lunar magma ocean. These observations were interpreted to reflect formation of the Moon and crystallization of the lunar magma ocean after 182Hf was no longer extant—that is, more than about 60 million years after the Solar System formed. Here we present W isotope data for three lunar samples that are more precise by a factor of ≥4 than those previously reported. The new data reveal that the lunar mantle has a well-resolved 182W excess of 20.6 ± 5.1 parts per million (±2 standard deviations), relative to the modern terrestrial mantle. The offset between the mantles of the Moon and the modern Earth is best explained by assuming that the W isotopic compositions of the two bodies were identical immediately following formation of the Moon, and that they then diverged as a result of disproportional late accretion to the Earth and Moon. One implication of this model is that metal from the core of the Moon-forming impactor must have efficiently stripped the Earth’s mantle of highly siderophile elements on its way to merge with the terrestrial core, requiring a substantial, but still poorly defined, level of metal–silicate equilibration.

Categories: Literature

Lunar tungsten isotopic evidence for the late veneer

Nature - Wed, 04/08/2015 - 00:00

Lunar tungsten isotopic evidence for the late veneer

Nature 520, 7548 (2015). doi:10.1038/nature14360

Authors: Thomas S. Kruijer, Thorsten Kleine, Mario Fischer-Gödde & Peter Sprung

According to the most widely accepted theory of lunar origin, a giant impact on the Earth led to the formation of the Moon, and also initiated the final stage of the formation of the Earth’s core. Core formation should have removed the highly siderophile elements (HSE) from Earth’s primitive mantle (that is, the bulk silicate Earth), yet HSE abundances are higher than expected. One explanation for this overabundance is that a ‘late veneer’ of primitive material was added to the bulk silicate Earth after the core formed. To test this hypothesis, tungsten isotopes are useful for two reasons: first, because the late veneer material had a different 182W/184W ratio to that of the bulk silicate Earth, and second, proportionally more material was added to the Earth than to the Moon. Thus, if a late veneer did occur, the bulk silicate Earth and the Moon must have different 182W/184W ratios. Moreover, the Moon-forming impact would also have created 182W differences because the mantle and core material of the impactor with distinct 182W/184W would have mixed with the proto-Earth during the giant impact. However the 182W/184W of the Moon has not been determined precisely enough to identify signatures of a late veneer or the giant impact. Here, using more-precise measurement techniques, we show that the Moon exhibits a 182W excess of 27 ± 4 parts per million over the present-day bulk silicate Earth. This excess is consistent with the expected 182W difference resulting from a late veneer with a total mass and composition inferred from HSE systematics. Thus, our data independently show that HSE abundances in the bulk silicate Earth were established after the giant impact and core formation, as predicted by the late veneer hypothesis. But, unexpectedly, we find that before the late veneer, no 182W anomaly existed between the bulk silicate Earth and the Moon, even though one should have arisen through the giant impact. The origin of the homogeneous 182W of the pre-late-veneer bulk silicate Earth and the Moon is enigmatic and constitutes a challenge to current models of lunar origin.

Categories: Literature

Scientists share inspiration on Twitter with #IAmAScientistBecause and #BeyondMarieCurie

Nature - Wed, 04/08/2015 - 00:00

Scientists share inspiration on Twitter with #IAmAScientistBecause and #BeyondMarieCurie

Nature 520, 7547 (2015). doi:10.1038/520267f

Author: Chris Woolston

Feel-good memes dominate social media in celebration of research and women scientists.

Categories: Literature

Cancer: An extravascular route for tumour cells

Nature - Wed, 04/08/2015 - 00:00

Cancer: An extravascular route for tumour cells

Nature 520, 7547 (2015). doi:10.1038/nature14382

Authors: Mary J. C. Hendrix

Molecular tracing of populations of breast-cancer cells in a primary tumour in mice reveals that two proteins, Serpine2 and Slpi, enable tumour cells to form vascular-like networks, facilitating perfusion and metastasis. See Letter p.358

Categories: Literature

Particle physics: A weighty mass difference

Nature - Wed, 04/08/2015 - 00:00

Particle physics: A weighty mass difference

Nature 520, 7547 (2015). doi:10.1038/nature14381

Authors: Frank Wilczek

The neutron–proton mass difference, one of the most consequential parameters of physics, has now been calculated from fundamental theories. This landmark calculation portends revolutionary progress in nuclear physics.

Categories: Literature

Ecology: Recovering the potential of coral reefs

Nature - Wed, 04/08/2015 - 00:00

Ecology: Recovering the potential of coral reefs

Nature 520, 7547 (2015). doi:10.1038/nature14384

Authors: Nicholas K. Dulvy & Holly K. Kindsvater

An analysis of fish declines in coral reefs shows that simple fishing limits and implementation of marine protected areas can be enough to support recovery of coral ecosystem resilience. See Letter p.341

Categories: Literature

Crystal structures of the human adiponectin receptors

Nature - Wed, 04/08/2015 - 00:00

Crystal structures of the human adiponectin receptors

Nature 520, 7547 (2015). doi:10.1038/nature14301

Authors: Hiroaki Tanabe, Yoshifumi Fujii, Miki Okada-Iwabu, Masato Iwabu, Yoshihiro Nakamura, Toshiaki Hosaka, Kanna Motoyama, Mariko Ikeda, Motoaki Wakiyama, Takaho Terada, Noboru Ohsawa, Masakatsu Hato, Satoshi Ogasawara, Tomoya Hino, Takeshi Murata, So Iwata, Kunio Hirata, Yoshiaki Kawano, Masaki Yamamoto, Tomomi Kimura-Someya, Mikako Shirouzu, Toshimasa Yamauchi, Takashi Kadowaki & Shigeyuki Yokoyama

Adiponectin stimulation of its receptors, AdipoR1 and AdipoR2, increases the activities of 5′ AMP-activated protein kinase (AMPK) and peroxisome proliferator-activated receptor (PPAR), respectively, thereby contributing to healthy longevity as key anti-diabetic molecules. AdipoR1 and AdipoR2 were predicted to contain seven transmembrane helices with the opposite topology

Categories: Literature

Recovery potential of the world's coral reef fishes

Nature - Wed, 04/08/2015 - 00:00

Recovery potential of the world's coral reef fishes

Nature 520, 7547 (2015). doi:10.1038/nature14358

Authors: M. Aaron MacNeil, Nicholas A. J. Graham, Joshua E. Cinner, Shaun K. Wilson, Ivor D. Williams, Joseph Maina, Steven Newman, Alan M. Friedlander, Stacy Jupiter, Nicholas V. C. Polunin & Tim R. McClanahan

Continuing degradation of coral reef ecosystems has generated substantial interest in how management can support reef resilience. Fishing is the primary source of diminished reef function globally, leading to widespread calls for additional marine reserves to recover fish biomass and restore key ecosystem functions. Yet there are no established baselines for determining when these conservation objectives have been met or whether alternative management strategies provide similar ecosystem benefits. Here we establish empirical conservation benchmarks and fish biomass recovery timelines against which coral reefs can be assessed and managed by studying the recovery potential of more than 800 coral reefs along an exploitation gradient. We show that resident reef fish biomass in the absence of fishing (B0) averages ∼1,000 kg ha−1, and that the vast majority (83%) of fished reefs are missing more than half their expected biomass, with severe consequences for key ecosystem functions such as predation. Given protection from fishing, reef fish biomass has the potential to recover within 35 years on average and less than 60 years when heavily depleted. Notably, alternative fisheries restrictions are largely (64%) successful at maintaining biomass above 50% of B0, sustaining key functions such as herbivory. Our results demonstrate that crucial ecosystem functions can be maintained through a range of fisheries restrictions, allowing coral reef managers to develop recovery plans that meet conservation and livelihood objectives in areas where marine reserves are not socially or politically feasible solutions.

Categories: Literature

A model of breast cancer heterogeneity reveals vascular mimicry as a driver of metastasis

Nature - Wed, 04/08/2015 - 00:00

A model of breast cancer heterogeneity reveals vascular mimicry as a driver of metastasis

Nature 520, 7547 (2015). doi:10.1038/nature14403

Authors: Elvin Wagenblast, Mar Soto, Sara Gutiérrez-Ángel, Christina A. Hartl, Annika L. Gable, Ashley R. Maceli, Nicolas Erard, Alissa M. Williams, Sun Y. Kim, Steffen Dickopf, J. Chuck Harrell, Andrew D. Smith, Charles M. Perou, John E. Wilkinson, Gregory J. Hannon & Simon R. V. Knott

Cancer metastasis requires that primary tumour cells evolve the capacity to intravasate into the lymphatic system or vasculature, and extravasate into and colonize secondary sites. Others have demonstrated that individual cells within complex populations show heterogeneity in their capacity to form secondary lesions. Here we develop a polyclonal mouse model of breast tumour heterogeneity, and show that distinct clones within a mixed population display specialization, for example, dominating the primary tumour, contributing to metastatic populations, or showing tropism for entering the lymphatic or vasculature systems. We correlate these stable properties to distinct gene expression profiles. Those clones that efficiently enter the vasculature express two secreted proteins, Serpine2 and Slpi, which were necessary and sufficient to program these cells for vascular mimicry. Our data indicate that these proteins not only drive the formation of extravascular networks but also ensure their perfusion by acting as anticoagulants. We propose that vascular mimicry drives the ability of some breast tumour cells to contribute to distant metastases while simultaneously satisfying a critical need of the primary tumour to be fed by the vasculature. Enforced expression of SERPINE2 and SLPI in human breast cancer cell lines also programmed them for vascular mimicry, and SERPINE2 and SLPI were overexpressed preferentially in human patients that had lung-metastatic relapse. Thus, these two secreted proteins, and the phenotype they promote, may be broadly relevant as drivers of metastatic progression in human cancer.

Categories: Literature

SHMT2 drives glioma cell survival in ischaemia but imposes a dependence on glycine clearance

Nature - Wed, 04/08/2015 - 00:00

SHMT2 drives glioma cell survival in ischaemia but imposes a dependence on glycine clearance

Nature 520, 7547 (2015). doi:10.1038/nature14363

Authors: Dohoon Kim, Brian P. Fiske, Kivanc Birsoy, Elizaveta Freinkman, Kenjiro Kami, Richard L. Possemato, Yakov Chudnovsky, Michael E. Pacold, Walter W. Chen, Jason R. Cantor, Laura M. Shelton, Dan Y. Gui, Manjae Kwon, Shakti H. Ramkissoon, Keith L. Ligon, Seong Woo Kang, Matija Snuderl, Matthew G. Vander Heiden & David M. Sabatini

Cancer cells adapt their metabolic processes to support rapid proliferation, but less is known about how cancer cells alter metabolism to promote cell survival in a poorly vascularized tumour microenvironment. Here we identify a key role for serine and glycine metabolism in the survival of brain cancer cells within the ischaemic zones of gliomas. In human glioblastoma multiforme, mitochondrial serine hydroxymethyltransferase (SHMT2) and glycine decarboxylase (GLDC) are highly expressed in the pseudopalisading cells that surround necrotic foci. We find that SHMT2 activity limits that of pyruvate kinase (PKM2) and reduces oxygen consumption, eliciting a metabolic state that confers a profound survival advantage to cells in poorly vascularized tumour regions. GLDC inhibition impairs cells with high SHMT2 levels as the excess glycine not metabolized by GLDC can be converted to the toxic molecules aminoacetone and methylglyoxal. Thus, SHMT2 is required for cancer cells to adapt to the tumour environment, but also renders these cells sensitive to glycine cleavage system inhibition.

Categories: Literature

Seeds of change

Nature - Wed, 04/08/2015 - 00:00

Seeds of change

Nature 520, 7546 (2015). doi:10.1038/520131b

The European Union faces a fresh battle over next-generation plant-breeding techniques.

Categories: Literature

Lunar affairs

Nature - Wed, 04/08/2015 - 00:00

Lunar affairs

Nature 520, 7546 (2015). doi:10.1038/520132a

A study in Nature adds a dramatic twist to the backstory of a neighbour we thought we knew.

Categories: Literature

Test the effects of ash on jet engines

Nature - Wed, 04/08/2015 - 00:00

Test the effects of ash on jet engines

Nature 520, 7546 (2015). http://www.nature.com/doifinder/10.1038/520133a

Author: Matthew Watson

To judge the safety of flying during an eruption, the airline industry cannot just rely on advances in volcanic monitoring and prediction, says Matthew Watson.

Categories: Literature

Glaciology: Few Canadian glaciers left by 2100

Nature - Wed, 04/08/2015 - 00:00

Glaciology: Few Canadian glaciers left by 2100

Nature 520, 7546 (2015). doi:10.1038/520134a

Mountain glaciers in western Canada could shrink by 70% relative to 2005 levels by the end of the century as a result of global warming.Garry Clarke of the University of British Columbia in Vancouver, Canada, and his colleagues built a high-resolution model that includes

Categories: Literature

Marine biology: Sea creatures adapt to acid

Nature - Wed, 04/08/2015 - 00:00

Marine biology: Sea creatures adapt to acid

Nature 520, 7546 (2015). doi:10.1038/520134b

Sea urchins can radically alter their energy use to cope with more-acidic oceans.Donal Manahan led a team at the University of Southern California in Los Angeles that grew Strongylocentrotus purpuratus urchins in current seawater conditions and in more-acidic conditions that are expected under

Categories: Literature

Palaeontology: Mesozoic insect mothering

Nature - Wed, 04/08/2015 - 00:00

Palaeontology: Mesozoic insect mothering

Nature 520, 7546 (2015). doi:10.1038/520134c

Insects that care for their young have been around for at least 95 million years, the discovery of an amber-entombed bug from Myanmar suggests.All kinds of extant insects care for their offspring, including some species of scale insect (Coccoidea) that hatch their young from

Categories: Literature

Avian biology: Small bird takes big journey

Nature - Wed, 04/08/2015 - 00:00

Avian biology: Small bird takes big journey

Nature 520, 7546 (2015). doi:10.1038/520134d

An extraordinary feat of migration has been confirmed in a tiny songbird that weighs just 12 grams.Blackpoll warblers (Setophaga striata) have long been thought to fly non-stop from northeastern North America to the Caribbean or South America. William DeLuca of the University

Categories: Literature

Neuroscience: How to form a fake memory in mice

Nature - Wed, 04/08/2015 - 00:00

Neuroscience: How to form a fake memory in mice

Nature 520, 7546 (2015). doi:10.1038/520135a

Unrelated memories can be artificially linked by activating distinct groups of neurons at the same time.Kaoru Inokuchi at the University of Toyama, Japan, and his colleagues let mice explore a cylindrical container. Later they placed the mice in a cubic box and gave them

Categories: Literature

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