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As Drought Grips South Africa, A Conflict Over Water and Coal

Yale Environment 360 - Mon, 05/16/2016 - 07:31

Facing one of the worst droughts in memory, South Africa’s leaders have doubled down on their support of the water-intensive coal industry. But clean energy advocates say the smartest move would be to back the country’s burgeoning wind and solar power sectors. BY KEITH SCHNEIDER

Categories: Environmental News

Mirror-image enzyme copies looking-glass DNA

Nature - Mon, 05/16/2016 - 00:00

Mirror-image enzyme copies looking-glass DNA

Nature 533, 7603 (2016). http://www.nature.com/doifinder/10.1038/nature.2016.19918

Author: Mark Peplow

Synthetic polymerase is a small step along the way to mirrored life forms.

Categories: Literature

Saving Amphibians: The Quest To Protect Threatened Species

Yale Environment 360 - Thu, 05/12/2016 - 07:35

The decline of the world’s amphibians continues, with causes ranging from fungal diseases to warmer and drier climates. Now, researchers are looking at ways to intervene with triage measures that could help save the most vulnerable populations. BY JIM ROBBINS

Categories: Environmental News

Despite Push for Renewables, Fossil Fuels Likely to Dominate in 2040

Yale Environment 360 - Thu, 05/12/2016 - 00:40

World leaders pledged last year in Paris to cut CO2 emissions and limit global warming to 2 degrees Celsius. Despite these promises, U.S. analysts said Wednesday that fossil fuels

EveryCarListed/Flickr — including coal — will still likely be the world’s primary source of energy in 2040. The findings are part of the U.S. Energy Information Administration’s annual World Energy Outlook report. Electricity from wind, solar, and hydropower will grow 2.9 percent annually, the report concluded, and by 2040, renewables, coal, and natural gas will each generate one-third of the world’s electricity. But diesel and gasoline will still power the majority of vehicles, with electric cars making up only 1 percent of the market, the report said. The report also found that carbon emissions from energy consumption in the developing world could grow 51 percent from 2012 to 2040 as countries like India and China modernize their economies, particularly by using coal.

Categories: Environmental News

Demotion of science ministry angers beleaguered Brazilian researchers

Nature - Thu, 05/12/2016 - 00:00

Demotion of science ministry angers beleaguered Brazilian researchers

Nature 533, 7603 (2016). http://www.nature.com/doifinder/10.1038/nature.2016.19910

Author: Claudio Angelo

New President Michel Temer — who replaces impeached Dilma Rousseff — is fusing the science and telecommunications ministries. 

Categories: Literature

Policy: Global standards for stem-cell research

Nature - Thu, 05/12/2016 - 00:00

Policy: Global standards for stem-cell research

Nature 533, 7603 (2016). doi:10.1038/533311a

Authors: Jonathan Kimmelman, Insoo Hyun, Nissim Benvenisty, Timothy Caulfield, Helen E. Heslop, Charles E. Murry, Douglas Sipp, Lorenz Studer, Jeremy Sugarman & George Q. Daley

New guidelines from the International Society for Stem Cell Research offer a model for self-regulation in contentious areas, write Jonathan Kimmelman and colleagues.

Categories: Literature

Bringing Energy Upgrades To the Nation’s Inner Cities

Yale Environment 360 - Wed, 05/11/2016 - 07:23

America’s low-income urban areas are filled with aging buildings that are notoriously energy-inefficient. It’s a problem that Donnel Baird sees as an opportunity. Baird is CEO and cofounder of BlocPower,

Donnel Baird a startup that markets and finances energy-upgrade projects in financially underserved areas. Founded in 2013 with venture capital seed money, BlocPower bundles small energy-improvement projects together — from barber shops to churches —and sells them to potential investors. In an interview with Yale Environment 360, Baird describes how BlocPower’s projects not only create jobs and reduce carbon emissions, but also raise awareness of global warming in inner-city communities. “It is not possible for the climate change movement to win anything significant without the participation of people of color,” says Baird.
Read the interview.

Categories: Environmental News

Cell biology: Choreography of protein synthesis

Nature - Wed, 05/11/2016 - 00:00

Cell biology: Choreography of protein synthesis

Nature 533, 7604 (2016). doi:10.1038/nature18436

Authors: Martin Ott

Both nuclear genes and genes in organelles called mitochondria are involved in the assembly of the cellular energy-producing machinery. RNA-translation programs that coordinate the two systems have now been identified. See Article p.499

Categories: Literature

Synchronized mitochondrial and cytosolic translation programs

Nature - Wed, 05/11/2016 - 00:00

Synchronized mitochondrial and cytosolic translation programs

Nature 533, 7604 (2016). doi:10.1038/nature18015

Authors: Mary T. Couvillion, Iliana C. Soto, Gergana Shipkovenska & L. Stirling Churchman

Oxidative phosphorylation (OXPHOS) is a vital process for energy generation, and is carried out by complexes within the mitochondria. OXPHOS complexes pose a unique challenge for cells because their subunits are encoded on both the nuclear and the mitochondrial genomes. Genomic approaches designed to study

Categories: Literature

A resonant chain of four transiting, sub-Neptune planets

Nature - Wed, 05/11/2016 - 00:00

A resonant chain of four transiting, sub-Neptune planets

Nature 533, 7604 (2016). doi:10.1038/nature17445

Authors: Sean M. Mills, Daniel C. Fabrycky, Cezary Migaszewski, Eric B. Ford, Erik Petigura & Howard Isaacson

Surveys have revealed many multi-planet systems containing super-Earths and Neptunes in orbits of a few days to a few months. There is debate whether in situ assembly or inward migration is the dominant mechanism of the formation of such planetary systems. Simulations suggest that migration creates tightly packed systems with planets whose orbital periods may be expressed as ratios of small integers (resonances), often in a many-planet series (chain). In the hundreds of multi-planet systems of sub-Neptunes, more planet pairs are observed near resonances than would generally be expected, but no individual system has hitherto been identified that must have been formed by migration. Proximity to resonance enables the detection of planets perturbing each other. Here we report transit timing variations of the four planets in the Kepler-223 system, model these variations as resonant-angle librations, and compute the long-term stability of the resonant chain. The architecture of Kepler-223 is too finely tuned to have been formed by scattering, and our numerical simulations demonstrate that its properties are natural outcomes of the migration hypothesis. Similar systems could be destabilized by any of several mechanisms, contributing to the observed orbital-period distribution, where many planets are not in resonances. Planetesimal interactions in particular are thought to be responsible for establishing the current orbits of the four giant planets in the Solar System by disrupting a theoretical initial resonant chain similar to that observed in Kepler-223.

Categories: Literature

Genome-wide association study identifies 74 loci associated with educational attainment

Nature - Wed, 05/11/2016 - 00:00

Genome-wide association study identifies 74 loci associated with educational attainment

Nature 533, 7604 (2016). doi:10.1038/nature17671

Authors: Aysu Okbay, Jonathan P. Beauchamp, Mark Alan Fontana, James J. Lee, Tune H. Pers, Cornelius A. Rietveld, Patrick Turley, Guo-Bo Chen, Valur Emilsson, S. Fleur W. Meddens, Sven Oskarsson, Joseph K. Pickrell, Kevin Thom, Pascal Timshel, Ronald de Vlaming, Abdel Abdellaoui, Tarunveer S. Ahluwalia, Jonas Bacelis, Clemens Baumbach, Gyda Bjornsdottir, Johannes H. Brandsma, Maria Pina Concas, Jaime Derringer, Nicholas A. Furlotte, Tessel E. Galesloot, Giorgia Girotto, Richa Gupta, Leanne M. Hall, Sarah E. Harris, Edith Hofer, Momoko Horikoshi, Jennifer E. Huffman, Kadri Kaasik, Ioanna P. Kalafati, Robert Karlsson, Augustine Kong, Jari Lahti, Sven J. van der Lee, Christiaan deLeeuw, Penelope A. Lind, Karl-Oskar Lindgren, Tian Liu, Massimo Mangino, Jonathan Marten, Evelin Mihailov, Michael B. Miller, Peter J. van der Most, Christopher Oldmeadow, Antony Payton, Natalia Pervjakova, Wouter J. Peyrot, Yong Qian, Olli Raitakari, Rico Rueedi, Erika Salvi, Börge Schmidt, Katharina E. Schraut, Jianxin Shi, Albert V. Smith, Raymond A. Poot, Beate St Pourcain, Alexander Teumer, Gudmar Thorleifsson, Niek Verweij, Dragana Vuckovic, Juergen Wellmann, Harm-Jan Westra, Jingyun Yang, Wei Zhao, Zhihong Zhu, Behrooz Z. Alizadeh, Najaf Amin, Andrew Bakshi, Sebastian E. Baumeister, Ginevra Biino, Klaus Bønnelykke, Patricia A. Boyle, Harry Campbell, Francesco P. Cappuccio, Gail Davies, Jan-Emmanuel De Neve, Panos Deloukas, Ilja Demuth, Jun Ding, Peter Eibich, Lewin Eisele, Niina Eklund, David M. Evans, Jessica D. Faul, Mary F. Feitosa, Andreas J. Forstner, Ilaria Gandin, Bjarni Gunnarsson, Bjarni V. Halldórsson, Tamara B. Harris, Andrew C. Heath, Lynne J. Hocking, Elizabeth G. Holliday, Georg Homuth, Michael A. Horan, Jouke-Jan Hottenga, Philip L. de Jager, Peter K. Joshi, Astanand Jugessur, Marika A. Kaakinen, Mika Kähönen, Stavroula Kanoni, Liisa Keltigangas-Järvinen, Lambertus A. L. M. Kiemeney, Ivana Kolcic, Seppo Koskinen, Aldi T. Kraja, Martin Kroh, Zoltan Kutalik, Antti Latvala, Lenore J. Launer, Maël P. Lebreton, Douglas F. Levinson, Paul Lichtenstein, Peter Lichtner, David C. M. Liewald, LifeLines Cohort Study, Anu Loukola, Pamela A. Madden, Reedik Mägi, Tomi Mäki-Opas, Riccardo E. Marioni, Pedro Marques-Vidal, Gerardus A. Meddens, George McMahon, Christa Meisinger, Thomas Meitinger, Yusplitri Milaneschi, Lili Milani, Grant W. Montgomery, Ronny Myhre, Christopher P. Nelson, Dale R. Nyholt, William E. R. Ollier, Aarno Palotie, Lavinia Paternoster, Nancy L. Pedersen, Katja E. Petrovic, David J. Porteous, Katri Räikkönen, Susan M. Ring, Antonietta Robino, Olga Rostapshova, Igor Rudan, Aldo Rustichini, Veikko Salomaa, Alan R. Sanders, Antti-Pekka Sarin, Helena Schmidt, Rodney J. Scott, Blair H. Smith, Jennifer A. Smith, Jan A. Staessen, Elisabeth Steinhagen-Thiessen, Konstantin Strauch, Antonio Terracciano, Martin D. Tobin, Sheila Ulivi, Simona Vaccargiu, Lydia Quaye, Frank J. A. van Rooij, Cristina Venturini, Anna A. E. Vinkhuyzen, Uwe Völker, Henry Völzke, Judith M. Vonk, Diego Vozzi, Johannes Waage, Erin B. Ware, Gonneke Willemsen, John R. Attia, David A. Bennett, Klaus Berger, Lars Bertram, Hans Bisgaard, Dorret I. Boomsma, Ingrid B. Borecki, Ute Bültmann, Christopher F. Chabris, Francesco Cucca, Daniele Cusi, Ian J. Deary, George V. Dedoussis, Cornelia M. van Duijn, Johan G. Eriksson, Barbara Franke, Lude Franke, Paolo Gasparini, Pablo V. Gejman, Christian Gieger, Hans-Jörgen Grabe, Jacob Gratten, Patrick J. F. Groenen, Vilmundur Gudnason, Pim van der Harst, Caroline Hayward, David A. Hinds, Wolfgang Hoffmann, Elina Hyppönen, William G. Iacono, Bo Jacobsson, Marjo-Riitta Järvelin, Karl-Heinz Jöckel, Jaakko Kaprio, Sharon L. R. Kardia, Terho Lehtimäki, Steven F. Lehrer, Patrik K. E. Magnusson, Nicholas G. Martin, Matt McGue, Andres Metspalu, Neil Pendleton, Brenda W. J. H. Penninx, Markus Perola, Nicola Pirastu, Mario Pirastu, Ozren Polasek, Danielle Posthuma, Christine Power, Michael A. Province, Nilesh J. Samani, David Schlessinger, Reinhold Schmidt, Thorkild I. A. Sørensen, Tim D. Spector, Kari Stefansson, Unnur Thorsteinsdottir, A. Roy Thurik, Nicholas J. Timpson, Henning Tiemeier, Joyce Y. Tung, André G. Uitterlinden, Veronique Vitart, Peter Vollenweider, David R. Weir, James F. Wilson, Alan F. Wright, Dalton C. Conley, Robert F. Krueger, George Davey Smith, Albert Hofman, David I. Laibson, Sarah E. Medland, Michelle N. Meyer, Jian Yang, Magnus Johannesson, Peter M. Visscher, Tõnu Esko, Philipp D. Koellinger, David Cesarini & Daniel J. Benjamin

Educational attainment is strongly influenced by social and other environmental factors, but genetic factors are estimated to account for at least 20% of the variation across individuals. Here we report the results of a genome-wide association study (GWAS) for educational attainment that extends our earlier discovery sample of 101,069 individuals to 293,723 individuals, and a replication study in an independent sample of 111,349 individuals from the UK Biobank. We identify 74 genome-wide significant loci associated with the number of years of schooling completed. Single-nucleotide polymorphisms associated with educational attainment are disproportionately found in genomic regions regulating gene expression in the fetal brain. Candidate genes are preferentially expressed in neural tissue, especially during the prenatal period, and enriched for biological pathways involved in neural development. Our findings demonstrate that, even for a behavioural phenotype that is mostly environmentally determined, a well-powered GWAS identifies replicable associated genetic variants that suggest biologically relevant pathways. Because educational attainment is measured in large numbers of individuals, it will continue to be useful as a proxy phenotype in efforts to characterize the genetic influences of related phenotypes, including cognition and neuropsychiatric diseases.

Categories: Literature

Neuroscience: Virtual reality explored

Nature - Wed, 05/11/2016 - 00:00

Neuroscience: Virtual reality explored

Nature 533, 7603 (2016). doi:10.1038/nature17899

Authors: Matthias Minderer, Christopher D. Harvey, Flavio Donato & Edvard I. Moser

Neuroscientists are increasingly using virtual reality to facilitate studies of animal behaviour, but whether behaviour in the virtual world mimics that in real life is a matter for debate. Here, scientists discuss the strengths and limitations of the approach.

Categories: Literature

Structural biology: Snapshots of transcription initiation

Nature - Wed, 05/11/2016 - 00:00

Structural biology: Snapshots of transcription initiation

Nature 533, 7603 (2016). doi:10.1038/nature18437

Authors: Steven Hahn & Stephen Buratowski

The enzyme RNA polymerase II, along with several transcription factors, initiates DNA transcription. Analyses reveal the structures involved in this process in human and yeast cells at high-resolution. See Articles p.353 & p.359

Categories: Literature

Transcription initiation complex structures elucidate DNA opening

Nature - Wed, 05/11/2016 - 00:00

Transcription initiation complex structures elucidate DNA opening

Nature 533, 7603 (2016). doi:10.1038/nature17990

Authors: C. Plaschka, M. Hantsche, C. Dienemann, C. Burzinski, J. Plitzko & P. Cramer

Transcription of eukaryotic protein-coding genes begins with assembly of the RNA polymerase (Pol) II initiation complex and promoter DNA opening. Here we report cryo-electron microscopy (cryo-EM) structures of yeast initiation complexes containing closed and open DNA at resolutions of 8.8 Å and 3.6 Å, respectively. DNA is

Categories: Literature

Near-atomic resolution visualization of human transcription promoter opening

Nature - Wed, 05/11/2016 - 00:00

Near-atomic resolution visualization of human transcription promoter opening

Nature 533, 7603 (2016). doi:10.1038/nature17970

Authors: Yuan He, Chunli Yan, Jie Fang, Carla Inouye, Robert Tjian, Ivaylo Ivanov & Eva Nogales

In eukaryotic transcription initiation, a large multi-subunit pre-initiation complex (PIC) that assembles at the core promoter is required for the opening of the duplex DNA and identification of the start site for transcription by RNA polymerase II. Here we use cryo-electron microscropy (cryo-EM) to determine

Categories: Literature

Deep-sea diversity patterns are shaped by energy availability

Nature - Wed, 05/11/2016 - 00:00

Deep-sea diversity patterns are shaped by energy availability

Nature 533, 7603 (2016). doi:10.1038/nature17937

Authors: Skipton N. C. Woolley, Derek P. Tittensor, Piers K. Dunstan, Gurutzeta Guillera-Arroita, José J. Lahoz-Monfort, Brendan A. Wintle, Boris Worm & Timothy D. O’Hara

The deep ocean is the largest and least-explored ecosystem on Earth, and a uniquely energy-poor environment. The distribution, drivers and origins of deep-sea biodiversity remain unknown at global scales. Here we analyse a database of more than 165,000 distribution records of Ophiuroidea (brittle stars), a dominant component of sea-floor fauna, and find patterns of biodiversity unlike known terrestrial or coastal marine realms. Both patterns and environmental predictors of deep-sea (2,000–6,500 m) species richness fundamentally differ from those found in coastal (0–20 m), continental shelf (20–200 m), and upper-slope (200–2,000 m) waters. Continental shelf to upper-slope richness consistently peaks in tropical Indo-west Pacific and Caribbean (0–30°) latitudes, and is well explained by variations in water temperature. In contrast, deep-sea species show maximum richness at higher latitudes (30–50°), concentrated in areas of high carbon export flux and regions close to continental margins. We reconcile this structuring of oceanic biodiversity using a species–energy framework, with kinetic energy predicting shallow-water richness, while chemical energy (export productivity) and proximity to slope habitats drive deep-sea diversity. Our findings provide a global baseline for conservation efforts across the sea floor, and demonstrate that deep-sea ecosystems show a biodiversity pattern consistent with ecological theory, despite being different from other planetary-scale habitats.

Categories: Literature

Local fitness landscape of the green fluorescent protein

Nature - Wed, 05/11/2016 - 00:00

Local fitness landscape of the green fluorescent protein

Nature 533, 7603 (2016). doi:10.1038/nature17995

Authors: Karen S. Sarkisyan, Dmitry A. Bolotin, Margarita V. Meer, Dinara R. Usmanova, Alexander S. Mishin, George V. Sharonov, Dmitry N. Ivankov, Nina G. Bozhanova, Mikhail S. Baranov, Onuralp Soylemez, Natalya S. Bogatyreva, Peter K. Vlasov, Evgeny S. Egorov, Maria D. Logacheva, Alexey S. Kondrashov, Dmitry M. Chudakov, Ekaterina V. Putintseva, Ilgar Z. Mamedov, Dan S. Tawfik, Konstantin A. Lukyanov & Fyodor A. Kondrashov

Fitness landscapes depict how genotypes manifest at the phenotypic level and form the basis of our understanding of many areas of biology, yet their properties remain elusive. Previous studies have analysed specific genes, often using their function as a proxy for fitness, experimentally assessing the effect on function of single mutations and their combinations in a specific sequence or in different sequences. However, systematic high-throughput studies of the local fitness landscape of an entire protein have not yet been reported. Here we visualize an extensive region of the local fitness landscape of the green fluorescent protein from Aequorea victoria (avGFP) by measuring the native function (fluorescence) of tens of thousands of derivative genotypes of avGFP. We show that the fitness landscape of avGFP is narrow, with 3/4 of the derivatives with a single mutation showing reduced fluorescence and half of the derivatives with four mutations being completely non-fluorescent. The narrowness is enhanced by epistasis, which was detected in up to 30% of genotypes with multiple mutations and mostly occurred through the cumulative effect of slightly deleterious mutations causing a threshold-like decrease in protein stability and a concomitant loss of fluorescence. A model of orthologous sequence divergence spanning hundreds of millions of years predicted the extent of epistasis in our data, indicating congruence between the fitness landscape properties at the local and global scales. The characterization of the local fitness landscape of avGFP has important implications for several fields including molecular evolution, population genetics and protein design.

Categories: Literature

An obligatory role for neurotensin in high-fat-diet-induced obesity

Nature - Wed, 05/11/2016 - 00:00

An obligatory role for neurotensin in high-fat-diet-induced obesity

Nature 533, 7603 (2016). doi:10.1038/nature17662

Authors: Jing Li, Jun Song, Yekaterina Y. Zaytseva, Yajuan Liu, Piotr Rychahou, Kai Jiang, Marlene E. Starr, Ji Tae Kim, Jennifer W. Harris, Frederique B. Yiannikouris, Wendy S. Katz, Peter M. Nilsson, Marju Orho-Melander, Jing Chen, Haining Zhu, Timothy Fahrenholz, Richard M. Higashi, Tianyan Gao, Andrew J. Morris, Lisa A. Cassis, Teresa W. -M. Fan, Heidi L. Weiss, Paul R. Dobner, Olle Melander, Jianhang Jia & B. Mark Evers

Obesity and its associated comorbidities (for example, diabetes mellitus and hepatic steatosis) contribute to approximately 2.5 million deaths annually and are among the most prevalent and challenging conditions confronting the medical profession. Neurotensin (NT; also known as NTS), a 13-amino-acid peptide predominantly localized in specialized enteroendocrine cells of the small intestine and released by fat ingestion, facilitates fatty acid translocation in rat intestine, and stimulates the growth of various cancers. The effects of NT are mediated through three known NT receptors (NTR1, 2 and 3; also known as NTSR1, 2, and NTSR3, respectively). Increased fasting plasma levels of pro-NT (a stable NT precursor fragment produced in equimolar amounts relative to NT) are associated with increased risk of diabetes, cardiovascular disease and mortality; however, a role for NT as a causative factor in these diseases is unknown. Here we show that NT-deficient mice demonstrate significantly reduced intestinal fat absorption and are protected from obesity, hepatic steatosis and insulin resistance associated with high fat consumption. We further demonstrate that NT attenuates the activation of AMP-activated protein kinase (AMPK) and stimulates fatty acid absorption in mice and in cultured intestinal cells, and that this occurs through a mechanism involving NTR1 and NTR3 (also known as sortilin). Consistent with the findings in mice, expression of NT in Drosophila midgut enteroendocrine cells results in increased lipid accumulation in the midgut, fat body, and oenocytes (specialized hepatocyte-like cells) and decreased AMPK activation. Remarkably, in humans, we show that both obese and insulin-resistant subjects have elevated plasma concentrations of pro-NT, and in longitudinal studies among non-obese subjects, high levels of pro-NT denote a doubling of the risk of developing obesity later in life. Our findings directly link NT with increased fat absorption and obesity and suggest that NT may provide a prognostic marker of future obesity and a potential target for prevention and treatment.

Categories: Literature

Mothers’ milk

Nature - Wed, 05/11/2016 - 00:00

Mothers’ milk

Nature 533, 7602 (2016). doi:10.1038/533145a

The safe use of medicines during breastfeeding is not an easy topic to study, but new parents deserve better information on the risks and benefits.

Categories: Literature

Smoke out

Nature - Wed, 05/11/2016 - 00:00

Smoke out

Nature 533, 7602 (2016). doi:10.1038/533146a

Scientists should unite over electronic-cigarette regulation, or big tobacco will step in.

Categories: Literature

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