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Form and function of topologically associating genomic domains in budding yeast [Cell Biology]

PNAS Early Edition Articles - Mon, 03/27/2017 - 14:09
The genome of metazoan cells is organized into topologically associating domains (TADs) that have similar histone modifications, transcription level, and DNA replication timing. Although similar structures appear to be conserved in fission yeast, computational modeling and analysis of high-throughput chromosome conformation capture (Hi-C) data have been used to argue that...

Quantification of circulating Mycobacterium tuberculosis antigen peptides allows rapid diagnosis of active disease and treatment monitoring [Engineering]

PNAS Early Edition Articles - Mon, 03/27/2017 - 14:09
Tuberculosis (TB) is a major global health threat, resulting in an urgent unmet need for a rapid, non–sputum-based quantitative test to detect active Mycobacterium tuberculosis (Mtb) infections in clinically diverse populations and quickly assess Mtb treatment responses for emerging drug-resistant strains. We have identified Mtb-specific peptide fragments and developed a...

High-numerical-aperture cryogenic light microscopy for increased precision of superresolution reconstructions [Cell Biology]

PNAS Early Edition Articles - Mon, 03/27/2017 - 14:09
Superresolution microscopy has fundamentally altered our ability to resolve subcellular proteins, but improving on these techniques to study dense structures composed of single-molecule-sized elements has been a challenge. One possible approach to enhance superresolution precision is to use cryogenic fluorescent imaging, reported to reduce fluorescent protein bleaching rates, thereby increasing...

Origins of house mice in ecological niches created by settled hunter-gatherers in the Levant 15,000 y ago [Anthropology]

PNAS Early Edition Articles - Mon, 03/27/2017 - 14:09
Reductions in hunter-gatherer mobility during the Late Pleistocene influenced settlement ecologies, altered human relations with animal communities, and played a pivotal role in domestication. The influence of variability in human mobility on selection dynamics and ecological interactions in human settlements has not been extensively explored, however. This study of mice...

In situ characterization of cofacial Co(IV) centers in Co4O4 cubane: Modeling the high-valent active site in oxygen-evolving catalysts [Chemistry]

PNAS Early Edition Articles - Mon, 03/27/2017 - 14:09
The Co4O4 cubane is a representative structural model of oxidic cobalt oxygen-evolving catalysts (Co-OECs). The Co-OECs are active when residing at two oxidation levels above an all-Co(III) resting state. This doubly oxidized Co(IV)2 state may be captured in a Co(III)2(IV)2 cubane. We demonstrate that the Co(III)2(IV)2 cubane may be electrochemically...

Ancient palace complex (300-100 BC) discovered in the Valley of Oaxaca, Mexico [Anthropology]

PNAS Early Edition Articles - Mon, 03/27/2017 - 14:09
Recently completed excavations at the site of El Palenque in Mexico’s Valley of Oaxaca have recovered the well-preserved remains of a palace complex dated by associated radiocarbon samples and ceramics to the Late Formative period or Late Monte Albán I phase (300–100 BC), the period of archaic state emergence in...

Mouse-adapted MERS coronavirus causes lethal lung disease in human DPP4 knockin mice [Medical Sciences]

PNAS Early Edition Articles - Mon, 03/27/2017 - 14:09
The Middle East respiratory syndrome (MERS) emerged in Saudi Arabia in 2012, caused by a zoonotically transmitted coronavirus (CoV). Over 1,900 cases have been reported to date, with ∼36% fatality rate. Lack of autopsies from MERS cases has hindered understanding of MERS-CoV pathogenesis. A small animal model that develops progressive...

Communicating the deadly consequences of global warming for human heat stress [Environmental Sciences]

PNAS Early Edition Articles - Mon, 03/27/2017 - 14:09
In December of 2015, the international community pledged to limit global warming to below 2 °C above preindustrial (PI) to prevent dangerous climate change. However, to what extent, and for whom, is danger avoided if this ambitious target is realized? We address these questions by scrutinizing heat stress, because the...

Spemann organizer transcriptome induction by early beta-catenin, Wnt, Nodal, and Siamois signals in Xenopus laevis [Developmental Biology]

PNAS Early Edition Articles - Mon, 03/27/2017 - 14:09
The earliest event in Xenopus development is the dorsal accumulation of nuclear β-catenin under the influence of cytoplasmic determinants displaced by fertilization. In this study, a genome-wide approach was used to examine transcription of the 43,673 genes annotated in the Xenopus laevis genome under a variety of conditions that inhibit...

PLP and GABA trigger GabR-mediated transcription regulation in Bacillus subtilis via external aldimine formation [Biochemistry]

PNAS Early Edition Articles - Mon, 03/27/2017 - 14:09
The Bacillus subtilis protein regulator of the gabTD operon and its own gene (GabR) is a transcriptional activator that regulates transcription of γ-aminobutyric acid aminotransferase (GABA-AT; GabT) upon interactions with pyridoxal-5′-phosphate (PLP) and GABA, and thereby promotes the biosynthesis of glutamate from GABA. We show here that the external aldimine...

Splicing variation of Long-IRBIT determines the target selectivity of IRBIT family proteins [Cell Biology]

PNAS Early Edition Articles - Mon, 03/27/2017 - 14:09
IRBIT [inositol 1,4,5-trisphosphate receptor (IP3R) binding protein released with inositol 1,4,5-trisphosphate (IP3)] is a multifunctional protein that regulates several target molecules such as ion channels, transporters, polyadenylation complex, and kinases. Through its interaction with multiple targets, IRBIT contributes to calcium signaling, electrolyte transport, mRNA processing, cell cycle, and neuronal function....

Correction for Lee et al., MicroRNA-10a is crucial for endothelial response to different flow patterns via interaction of retinoid acid receptors and histone deacetylases [Corrections]

PNAS Early Edition Articles - Mon, 03/27/2017 - 14:09
PHYSIOLOGY Correction for “MicroRNA-10a is crucial for endothelial response to different flow patterns via interaction of retinoid acid receptors and histone deacetylases,” by Ding-Yu Lee, Ting-Er Lin, Chih-I Lee, Jing Zhou, Yi-Hsuan Huang, Pei-Ling Lee, Yu-Tsung Shih, Shu Chien, and Jeng-Jiann Chiu, which appeared in issue 8, February 21, 2017,...

Strategic siting and regional grid interconnections key to low-carbon futures in African countries [Sustainability Science]

PNAS Early Edition Articles - Mon, 03/27/2017 - 14:09
Recent forecasts suggest that African countries must triple their current electricity generation by 2030. Our multicriteria assessment of wind and solar potential for large regions of Africa shows how economically competitive and low-environmental–impact renewable resources can significantly contribute to meeting this demand. We created the Multicriteria Analysis for Planning Renewable...

Myosin-1E interacts with FAK proline-rich region 1 to induce fibronectin-type matrix [Cell Biology]

PNAS Early Edition Articles - Mon, 03/27/2017 - 14:09
Focal adhesion kinase (FAK) is a nonreceptor tyrosine kinase involved in development and human disease, including cancer. It is currently thought that the four-point one, ezrin, radixin, moesin (FERM)–kinase domain linker, which contains autophosphorylation site tyrosine (Y) 397, is not required for in vivo FAK function until late midgestation. Here,...

Evolution of the early Antarctic ice ages [Earth, Atmospheric, and Planetary Sciences]

PNAS Early Edition Articles - Mon, 03/27/2017 - 14:09
Understanding the stability of the early Antarctic ice cap in the geological past is of societal interest because present-day atmospheric CO2 concentrations have reached values comparable to those estimated for the Oligocene and the Early Miocene epochs. Here we analyze a new high-resolution deep-sea oxygen isotope (δ18O) record from the...

Climate change both facilitates and inhibits invasive plant ranges in New England [Ecology]

PNAS Early Edition Articles - Mon, 03/27/2017 - 14:09
Forecasting ecological responses to climate change, invasion, and their interaction must rely on understanding underlying mechanisms. However, such forecasts require extrapolation into new locations and environments. We linked demography and environment using experimental biogeography to forecast invasive and native species’ potential ranges under present and future climate in New England,...

High-throughput identification of small molecules that affect human embryonic vascular development [Applied Biological Sciences]

PNAS Early Edition Articles - Mon, 03/27/2017 - 14:09
Birth defects, which are in part caused by exposure to environmental chemicals and pharmaceutical drugs, affect 1 in every 33 babies born in the United States each year. The current standard to screen drugs that affect embryonic development is based on prenatal animal testing; however, this approach yields low-throughput and...

Nurr1:RXR{alpha} heterodimer activation as monotherapy for Parkinson’s disease [Neuroscience]

PNAS Early Edition Articles - Mon, 03/27/2017 - 14:09
Parkinson’s disease (PD) is a progressive neurodegenerative disorder characterized by the loss of dopaminergic (DAergic) neurons in the substantia nigra and the gradual depletion of dopamine (DA). Current treatments replenish the DA deficit and improve symptoms but induce dyskinesias over time, and neuroprotective therapies are nonexistent. Here we report that...

MYO6 is targeted by Salmonella virulence effectors to trigger PI3-kinase signaling and pathogen invasion into host cells [Cell Biology]

PNAS Early Edition Articles - Mon, 03/27/2017 - 14:09
To establish infections, Salmonella injects virulence effectors that hijack the host actin cytoskeleton and phosphoinositide signaling to drive pathogen invasion. How effectors reprogram the cytoskeleton network remains unclear. By reconstituting the activities of the Salmonella effector SopE, we recapitulated Rho GTPase-driven actin polymerization at model phospholipid membrane bilayers in cell-free...

The Time Has Come! Trump to roll back EPA Climate Regs

Climate Depot - Mon, 03/27/2017 - 12:50
http://www.eenews.net/climatewire/2017/03/27/stories/1060052111 Trump to roll back Clean Power Plan tomorrow Niina Heikkinen, E&E News reporter Published: Monday, March 27, 2017 Vice President Mike Pence visited Foster Supply Inc. on Saturday in Scott Depot, W.Va., where he declared the Obama-era “war on coal” to be over. Photo by Sholten Singer/The Herald-Dispatch, courtesy of AP Images. The White [...]
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