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World’s longest sea bridge opens between Hong Kong and mainland China

HIV and AIDS - 4 hours 14 min назад
The world's longest sea bridge has opened, connecting Hong Kong, Zhuhai, and Macau. It is 55 kilometres or 20 times longer than the Golden Gate Bridge
Категории: Healthcare, Science and society

Tiny supercomputers could be made from the skeleton inside your cells

HIV and AIDS - 6 hours 26 min назад
Building a computer out of the skeletons that hold our cells together could make them smaller and far more energy efficient
Категории: Healthcare, Science and society

Hot baths could improve depression as much as physical exercise

HIV and AIDS - 6 hours 1 min назад
Taking a hot bath twice a week may help relieve mild depression. It may work by resetting circadian rhythms, which are often disrupted in people with depression
Категории: Healthcare, Science and society

Structure of the <i>Macrobrachium rosenbergii</i> nodavirus: A new genus within the <i>Nodaviridae</i>?

PLOS Biology (new articles) - 18 hours 1 min назад

by Kok Lian Ho, Mads Gabrielsen, Poay Ling Beh, Chare Li Kueh, Qiu Xian Thong, James Streetley, Wen Siang Tan, David Bhella

Macrobrachium rosenbergii nodavirus (MrNV) is a pathogen of freshwater prawns that poses a threat to food security and causes significant economic losses in the aquaculture industries of many developing nations. A detailed understanding of the MrNV virion structure will inform the development of strategies to control outbreaks. The MrNV capsid has also been engineered to display heterologous antigens, and thus knowledge of its atomic resolution structure will benefit efforts to develop tools based on this platform. Here, we present an atomic-resolution model of the MrNV capsid protein (CP), calculated by cryogenic electron microscopy (cryoEM) of MrNV virus-like particles (VLPs) produced in insect cells, and three-dimensional (3D) image reconstruction at 3.3 Å resolution. CryoEM of MrNV virions purified from infected freshwater prawn post-larvae yielded a 6.6 Å resolution structure, confirming the biological relevance of the VLP structure. Our data revealed that unlike other known nodavirus structures, which have been shown to assemble capsids having trimeric spikes, MrNV assembles a T = 3 capsid with dimeric spikes. We also found a number of surprising similarities between the MrNV capsid structure and that of the Tombusviridae: 1) an extensive network of N-terminal arms (NTAs) lines the capsid interior, forming long-range interactions to lace together asymmetric units; 2) the capsid shell is stabilised by 3 pairs of Ca2+ ions in each asymmetric unit; 3) the protruding spike domain exhibits a very similar fold to that seen in the spikes of the tombusviruses. These structural similarities raise questions concerning the taxonomic classification of MrNV.
Категории: Biology, Journals

Quantitative assessment of cell population diversity in single-cell landscapes

PLOS Biology (new articles) - 18 hours 1 min назад

by Qi Liu, Charles A. Herring, Quanhu Sheng, Jie Ping, Alan J. Simmons, Bob Chen, Amrita Banerjee, Wei Li, Guoqiang Gu, Robert J. Coffey, Yu Shyr, Ken S. Lau

Single-cell RNA sequencing (scRNA-seq) has become a powerful tool for the systematic investigation of cellular diversity. As a number of computational tools have been developed to identify and visualize cell populations within a single scRNA-seq dataset, there is a need for methods to quantitatively and statistically define proportional shifts in cell population structures across datasets, such as expansion or shrinkage or emergence or disappearance of cell populations. Here we present sc-UniFrac, a framework to statistically quantify compositional diversity in cell populations between single-cell transcriptome landscapes. sc-UniFrac enables sensitive and robust quantification in simulated and experimental datasets in terms of both population identity and quantity. We have demonstrated the utility of sc-UniFrac in multiple applications, including assessment of biological and technical replicates, classification of tissue phenotypes and regional specification, identification and definition of altered cell infiltrates in tumorigenesis, and benchmarking batch-correction tools. sc-UniFrac provides a framework for quantifying diversity or alterations in cell populations across conditions and has broad utility for gaining insight into tissue-level perturbations at the single-cell resolution.
Категории: Biology, Journals

The microRNA-29/PGC1α regulatory axis is critical for metabolic control of cardiac function

PLOS Biology (new articles) - 18 hours 1 min назад

by Xurde M. Caravia, Víctor Fanjul, Eduardo Oliver, David Roiz-Valle, Alba Morán-Álvarez, Gabriela Desdín-Micó, María Mittelbrunn, Roberto Cabo, José A. Vega, Francisco Rodríguez, Antonio Fueyo, Mónica Gómez, Manuel Lobo-González, Héctor Bueno, Gloria Velasco, José M. P. Freije, Vicente Andrés, Borja Ibáñez, Alejandro P. Ugalde, Carlos López-Otín

Different microRNAs (miRNAs), including miR-29 family, may play a role in the development of heart failure (HF), but the underlying molecular mechanisms in HF pathogenesis remain unclear. We aimed at characterizing mice deficient in miR-29 in order to address the functional relevance of this family of miRNAs in the cardiovascular system and its contribution to heart disease. In this work, we show that mice deficient in miR-29a/b1 develop vascular remodeling and systemic hypertension, as well as HF with preserved ejection fraction (HFpEF) characterized by myocardial fibrosis, diastolic dysfunction, and pulmonary congestion, and die prematurely. We also found evidence that the absence of miR-29 triggers the up-regulation of its target, the master metabolic regulator PGC1α, which in turn generates profound alterations in mitochondrial biogenesis, leading to a pathological accumulation of small mitochondria in mutant animals that contribute to cardiac disease. Notably, we demonstrate that systemic hypertension and HFpEF caused by miR-29 deficiency can be rescued by PGC1α haploinsufficiency, which reduces cardiac mitochondrial accumulation and extends longevity of miR-29–mutant mice. In addition, PGC1α is overexpressed in hearts from patients with HF. Collectively, our findings demonstrate the in vivo role of miR-29 in cardiovascular homeostasis and unveil a novel miR-29/PGC1α regulatory circuitry of functional relevance for cell metabolism under normal and pathological conditions.
Категории: Biology, Journals

Hot baths could improve depression as much as physical exercise

Genetics - пн, 2018-10-22 18:58
Taking a hot bath twice a week may help relieve mild depression. It may work by resetting circadian rhythms, which are often disrupted in people with depression
Категории: Biology

Salty Martian groundwater may have enough oxygen to support life

Genetics - пн, 2018-10-22 17:00
Mars gets its red colour from oxygen rusting its surface, and it may be hiding even more oxygen in underground brine, which could help microorganisms survive
Категории: Biology

Salty Martian groundwater may have enough oxygen to support life

HIV and AIDS - пн, 2018-10-22 17:00
Mars gets its red colour from oxygen rusting its surface, and it may be hiding even more oxygen in underground brine, which could help microorganisms survive
Категории: Healthcare, Science and society

AI alchemists spit out the recipe for any molecule you want to make

Genetically modified organisms (GMO) - пн, 2018-10-22 12:30
It's a nightmarish amount of work to figure out how to build a molecule from scratch. Now machines can do it and it will mean a bounty of new drugs and materials
Категории: Science and society

AI alchemists spit out the recipe for any molecule you want to make

Genetics - пн, 2018-10-22 12:30
It's a nightmarish amount of work to figure out how to build a molecule from scratch. Now machines can do it and it will mean a bounty of new drugs and materials
Категории: Biology

Red Moon review: History lessons power great new lunar future novel

Genetically modified organisms (GMO) - сб, 2018-10-20 11:00
According to the new book by science-fiction author Kim Stanley Robinson, China's long past makes its domination of the moon inevitable
Категории: Science and society

Red Moon review: History lessons power great new lunar future novel

Genetics - сб, 2018-10-20 11:00
According to the new book by science-fiction author Kim Stanley Robinson, China's long past makes its domination of the moon inevitable
Категории: Biology

An alternative mode of epithelial polarity in the <i>Drosophila</i> midgut

PLOS Biology (new articles) - пт, 2018-10-19 23:00

by Jia Chen, Aram-Christopher Sayadian, Nick Lowe, Holly E. Lovegrove, Daniel St Johnston

Apical–basal polarity is essential for the formation and function of epithelial tissues, whereas loss of polarity is a hallmark of tumours. Studies in Drosophila have identified conserved polarity factors that define the apical (Crumbs, Stardust, Par-6, atypical protein kinase C [aPKC]), junctional (Bazooka [Baz]/Par-3), and basolateral (Scribbled [Scrib], Discs large [Dlg], Lethal [2] giant larvae [Lgl]) domains of epithelial cells. Because these conserved factors mark equivalent domains in diverse types of vertebrate and invertebrate epithelia, it is generally assumed that this system underlies polarity in all epithelia. Here, we show that this is not the case, as none of these canonical factors are required for the polarisation of the endodermal epithelium of the Drosophila adult midgut. Furthermore, like vertebrate epithelia but not other Drosophila epithelia, the midgut epithelium forms occluding junctions above adherens junctions (AJs) and requires the integrin adhesion complex for polarity. Thus, Drosophila contains two types of epithelia that polarise by fundamentally different mechanisms. This diversity of epithelial types may reflect their different developmental origins, junctional arrangement, or whether they polarise in an apical–basal direction or vice versa. Since knock-outs of canonical polarity factors in vertebrates often have little or no effect on epithelial polarity and the Drosophila midgut shares several common features with vertebrate epithelia, this diversity of polarity mechanisms is likely to be conserved in other animals.
Категории: Biology, Journals

EBP1 nuclear accumulation negatively feeds back on FERONIA-mediated RALF1 signaling

PLOS Biology (new articles) - пт, 2018-10-19 23:00

by Chiyu Li, Xuanming Liu, Xiaonan Qiang, Xiaoyan Li, Xiushan Li, Sirui Zhu, Long Wang, Yuan Wang, Hongdong Liao, Sheng Luan, Feng Yu

FERONIA (FER), a plasma membrane receptor-like kinase, is a central regulator of cell growth that integrates environmental and endogenous signals. A peptide ligand rapid alkalinization factor 1 (RALF1) binds to FER and triggers a series of downstream events, including inhibition of Arabidopsis H+-ATPase 2 activity at the cell surface and regulation of gene expression in the nucleus. We report here that, upon RALF1 binding, FER first promotes ErbB3-binding protein 1 (EBP1) mRNA translation and then interacts with and phosphorylates the EBP1 protein, leading to EBP1 accumulation in the nucleus. There, EBP1 associates with the promoters of previously identified RALF1-regulated genes, such as CML38, and regulates gene transcription in response to RALF1 signaling. EBP1 appears to inhibit the RALF1 peptide response, thus forming a transcription–translation feedback loop (TTFL) similar to that found in circadian rhythm control. The plant RALF1-FER-EBP1 axis is reminiscent of animal epidermal growth factor receptor (EGFR) signaling, in which EGF peptide induces EGFR to interact with and phosphorylate EBP1, promoting EBP1 nuclear accumulation to control cell growth. Thus, we suggest that in response to peptide signals, plant FER and animal EGFR use the conserved key regulator EBP1 to control cell growth in the nucleus.
Категории: Biology, Journals

Frontostriatal pathways gate processing of behaviorally relevant reward dimensions

PLOS Biology (new articles) - пт, 2018-10-19 23:00

by Susanna C. Weber, Thorsten Kahnt, Boris B. Quednow, Philippe N. Tobler

The value of rewards arises from multiple hedonic and motivational dimensions. Reward-encoding brain regions such as the ventral striatum (VS) are known to process these dimensions. However, the mechanism whereby distinct reward dimensions are selected for neural processing and guiding behavior remains unclear. Here, we used functional imaging to investigate how human individuals make either hedonic (liking) or motivational (wanting) evaluations of everyday items. We found that the two types of evaluations were differently modulated depending on whether participants won or lost these items. Neural activity in the VS encoded both hedonic and motivational dimensions of reward, whereas ventromedial prefrontal activity encoded primarily motivational evaluations and central orbitofrontal activity encoded predominantly hedonic evaluations. These distinct prefrontal representations arose regardless of which judgment was currently relevant for behavior. Critically, the VS preferentially processed the reward dimension currently being evaluated and showed judgment-specific functional connectivity with the dimension-specific prefrontal areas. Thus, our data are in keeping with a gating mechanism by which prefrontal cortex (PFC)–VS pathways flexibly encode reward dimensions depending on their behavioral relevance. These findings provide a prototype for a generalized information selection mechanism through content-tailored frontostriatal communication.
Категории: Biology, Journals

Supercharged geothermal energy could power the planet

Genetics - пт, 2018-10-19 13:00
The next generation of geothermal plants will unlock more of Earth's bountiful, underground energy and could allow the technology to finally fulfil its promise
Категории: Biology

Supercharged geothermal energy could power the planet

Genetically modified organisms (GMO) - пт, 2018-10-19 13:00
The next generation of geothermal plants will unlock more of Earth's bountiful, underground energy and could allow the technology to finally fulfil its promise
Категории: Science and society

7 explanations for why mysterious radio bursts are coming from space

Genetics - пт, 2018-10-19 12:30
Astronomers are scratching their heads over extremely fast radio bursts. Now they're making a list of all the theories for what - or who - is making them
Категории: Biology

7 explanations for why mysterious radio bursts are coming from space

HIV and AIDS - пт, 2018-10-19 12:30
Astronomers are scratching their heads over extremely fast radio bursts. Now they're making a list of all the theories for what - or who - is making them
Категории: Healthcare, Science and society