A tumor-associated splice-isoform of MAP2K7 drives dedifferentiation in MBNL1-low cancers via JNK activation [Cell Biology]
Master splicing regulator MBNL1 shapes large transcriptomic changes that drive cellular differentiation during development. Here we demonstrate that MBNL1 is a suppressor of tumor dedifferentiation. We surveyed MBNL1 expression in matched tumor/normal pairs across The Cancer Genome Atlas and found that MBNL1 was down-regulated in several common cancers. Down-regulation of... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: Debleena Ray, Yu Chye Yun, Muhammad Idris, Shanshan Cheng, Arnoud Boot, Tan Bee Huat Iain, Steven G. Rozen, Patrick Tan, David M. Epstein Tags: Biological Sciences Source Type: research

An essential role for cardiolipin in the stability and function of the mitochondrial calcium uniporter [Cell Biology]
Calcium uptake by the mitochondrial calcium uniporter coordinates cytosolic signaling events with mitochondrial bioenergetics. During the past decade all protein components of the mitochondrial calcium uniporter have been identified, including MCU, the pore-forming subunit. However, the specific lipid requirements, if any, for the function and formation of this channel complex... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: Sagnika Ghosh, Writoban Basu Ball, Travis R. Madaris, Subramanya Srikantan, Muniswamy Madesh, Vamsi K. Mootha, Vishal M. Gohil Tags: Biological Sciences Source Type: research

Acquirement of water-splitting ability and alteration of the charge-separation mechanism in photosynthetic reaction centers [Biophysics and Computational Biology]
In photosynthetic reaction centers from purple bacteria (PbRC) and the water-oxidizing enzyme, photosystem II (PSII), charge separation occurs along one of the two symmetrical electron-transfer branches. Here we report the microscopic origin of the unidirectional charge separation, fully considering electron–hole interaction, electronic coupling of the pigments, and electrostatic interaction with... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: Hiroyuki Tamura, Keisuke Saito, Hiroshi Ishikita Tags: Biological Sciences Source Type: research

Maturation of the functional mouse CRES amyloid from globular form [Biophysics and Computational Biology]
The epididymal lumen contains a complex cystatin-rich nonpathological amyloid matrix with putative roles in sperm maturation and sperm protection. Given our growing understanding for the biological function of this and other functional amyloids, the problem still remains: how functional amyloids assemble including their initial transition to early oligomeric forms. To... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: Aveline Hewetson, Nazmul H. Khan, Matthew J. Dominguez, Hoa Quynh Do, R. E. Kusko, Collin G. Borcik, Daniel J. Rigden, Ronan M. Keegan, R. Bryan Sutton, Michael P. Latham, Benjamin J. Wylie, Gail A. Cornwall Tags: Biological Sciences Source Type: research

The interplay between chromophore and protein determines the extended excited state dynamics in a single-domain phytochrome [Biophysics and Computational Biology]
Phytochromes are a diverse family of bilin-binding photoreceptors that regulate a wide range of physiological processes. Their photochemical properties make them attractive for applications in optogenetics and superresolution microscopy. Phytochromes undergo reversible photoconversion triggered by the Z ⇄ E photoisomerization about the double bond in the bilin chromophore. However, it... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: Chavdar Slavov, Tobias Fischer, Avishai Barnoy, Heewhan Shin, Aditya G. Rao, Christian Wiebeler, Xiaoli Zeng, Yafang Sun, Qianzhao Xu, Alexander Gutt, Kai–Hong Zhao, Wolfgang Gartner, Xiaoȷing Yang, Igor Schapiro, Josef Wachtveitl Tags: Biological Sciences Source Type: research

Mechanism of {beta}-arrestin recruitment by the {mu}-opioid G protein-coupled receptor [Biophysics and Computational Biology]
Agonists to the μ-opioid G protein-coupled receptor (μOR) can alleviate pain through activation of G protein signaling, but they can also induce β-arrestin activation, leading to such side effects as respiratory depression. Biased ligands to μOR that induce G protein signaling without inducing β-arrestin signaling can alleviate pain while reducing... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: Amirhossein Mafi, Soo-Kyung Kim, William A. Goddard III Tags: Biological Sciences Source Type: research

Enzymatic degradation of liquid droplets of DNA is modulated near the phase boundary [Biophysics and Computational Biology]
Biomolecules can undergo liquid–liquid phase separation (LLPS), forming dense droplets that are increasingly understood to be important for cellular function. Analogous systems are studied as early-life compartmentalization mechanisms, for applications as protocells, or as drug-delivery vehicles. In many of these situations, interactions between the droplet and enzymatic solutes are important... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: Omar A. Saleh, Byoung-jin Jeon, Tim Liedl Tags: Physical Sciences Source Type: research

Active forces shape the metaphase spindle through a mechanical instability [Biophysics and Computational Biology]
The metaphase spindle is a dynamic structure orchestrating chromosome segregation during cell division. Recently, soft matter approaches have shown that the spindle behaves as an active liquid crystal. Still, it remains unclear how active force generation contributes to its characteristic spindle-like shape. Here we combine theory and experiments to show... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: David Oriola, Frank Julicher, Jan Brugues Tags: Physical Sciences Source Type: research

Disruption of evolutionarily correlated tRNA elements impairs accurate decoding [Biochemistry]
Bacterial transfer RNAs (tRNAs) contain evolutionarily conserved sequences and modifications that ensure uniform binding to the ribosome and optimal translational accuracy despite differences in their aminoacyl attachments and anticodon nucleotide sequences. In the tRNA anticodon stem−loop, the anticodon sequence is correlated with a base pair in the anticodon loop (nucleotides... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: Ha An Nguyen, S. Sunita, Christine M. Dunham Tags: Biological Sciences Source Type: research

Structural basis for the broad substrate specificity of two acyl-CoA dehydrogenases FadE5 from mycobacteria [Biochemistry]
FadE, an acyl-CoA dehydrogenase, introduces unsaturation to carbon chains in lipid metabolism pathways. Here, we report that FadE5 from Mycobacterium tuberculosis (MtbFadE5) and Mycobacterium smegmatis (MsFadE5) play roles in drug resistance and exhibit broad specificity for linear acyl-CoA substrates but have a preference for those with long carbon chains. Here,... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: Xiaobo Chen, Jiayue Chen, Bing Yan, Wei Zhang, Luke W. Guddat, Xiang Liu, Zihe Rao Tags: Biological Sciences Source Type: research

Real-time monitoring of peroxiredoxin oligomerization dynamics in living cells [Biochemistry]
Peroxiredoxins are central to cellular redox homeostasis and signaling. They serve as peroxide scavengers, sensors, signal transducers, and chaperones, depending on conditions and context. Typical 2-Cys peroxiredoxins are known to switch between different oligomeric states, depending on redox state, pH, posttranslational modifications, and other factors. Quaternary states and their changes... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: Daniel Pastor–Flores, Deepti Talwar, Brandan Pedre, Tobias P. Dick Tags: Biological Sciences Source Type: research

Dynamic human MutS{alpha}-MutL{alpha} complexes compact mismatched DNA [Biochemistry]
DNA mismatch repair (MMR) corrects errors that occur during DNA replication. In humans, mutations in the proteins MutSα and MutLα that initiate MMR cause Lynch syndrome, the most common hereditary cancer. MutSα surveilles the DNA, and upon recognition of a replication error it undergoes adenosine triphosphate-dependent conformational changes and recruits... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: Kira C. Bradford, Hunter Wilkins, Pengyu Hao, Zimeng M. Li, Bangchen Wang, Dan Burke, Dong Wu, Austin E. Smith, Logan Spaller, Chunwei Du, Jacob W. Gauer, Edward Chan, Peggy Hsieh, Keith R. Weninger, Dorothy A. Erie Tags: Biological Sciences Source Type: research

X-ray processing of a realistic ice mantle can explain the gas abundances in protoplanetary disks [Astronomy]
The Atacama Large Millimeter Array has allowed a detailed observation of molecules in protoplanetary disks, which can evolve toward solar systems like our own. While CO, CO2, HCO, and H2CO are often abundant species in the cold zones of the disk, CH3OH or CH3CN are only found in a few... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: Angela Ciaravella, Guillermo M. Munoz Caro, Antonio Jimenez–Escobar, Cesare Cecchi–Pestellini, Li–Chieh Hsiao, Chao–Hui Huang, Yu–Jung Chen Tags: Physical Sciences Source Type: research

Polarized evanescent waves reveal trochoidal dichroism [Applied Physical Sciences]
Matter’s sensitivity to light polarization is characterized by linear and circular polarization effects, corresponding to the system’s anisotropy and handedness, respectively. Recent investigations into the near-field properties of evanescent waves have revealed polarization states with out-of-phase transverse and longitudinal oscillations, resulting in trochoidal, or cartwheeling, field motion. Here, we demonstrate... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: Lauren A. McCarthy, Kyle W. Smith, Xiang Lan, Seyyed Ali Hosseini Jebeli, Luca Bursi, Alessandro Alabastri, Wei-Shun Chang, Peter Nordlander, Stephan Link Tags: Physical Sciences Source Type: research

Experimental realization of a reconfigurable electroacoustic topological insulator [Applied Physical Sciences]
A substantial challenge in guiding elastic waves is the presence of reflection and scattering at sharp edges, defects, and disorder. Recently, mechanical topological insulators have sought to overcome this challenge by supporting back-scattering resistant wave transmission. In this paper, we propose and experimentally demonstrate a reconfigurable electroacoustic topological insulator exhibiting... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: Amir Darabi, Manuel Collet, Michael J. Leamy Tags: Physical Sciences Source Type: research

Bioclickable and mussel adhesive peptide mimics for engineering vascular stent surfaces [Applied Physical Sciences]
Thrombogenic reaction, aggressive smooth muscle cell (SMC) proliferation, and sluggish endothelial cell (EC) migration onto bioinert metal vascular stents make poststenting reendothelialization a dilemma. Here, we report an easy to perform, biomimetic surface engineering strategy for multiple functionalization of metal vascular stents. We first design and graft a clickable mussel-inspired... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: Zhilu Yang, Xin Zhao, Rui Hao, Qiufen Tu, Xiaohua Tian, Yu Xiao, Kaiqing Xiong, Miao Wang, Yonghai Feng, Nan Huang, Guoqing Pan Tags: Physical Sciences Source Type: research

Highly tunable properties in pressure-treated two-dimensional Dion-Jacobson perovskites [Applied Physical Sciences]
The application of pressure can achieve novel structures and exotic phenomena in condensed matters. However, such pressure-induced transformations are generally reversible and useless for engineering materials for ambient-environment applications. Here, we report comprehensive high-pressure investigations on a series of Dion–Jacobson (D-J) perovskites A′An−1PbnI3n+1 [A′ = 3-(aminomethyl) piperidinium (3AMP), A =... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: Lingping Kong, Gang Liu, Jue Gong, Lingling Mao, Mengting Chen, Qingyang Hu, Xuȷie Lu, Wenge Yang, Mercouri G. Kanatzidis, Ho–kwang Mao Tags: Physical Sciences Source Type: research

Functional network analysis reveals an immune tolerance mechanism in cancer [Applied Mathematics]
We present a technique to construct a simplification of a feature network which can be used for interactive data exploration, biological hypothesis generation, and the detection of communities or modules of cofunctional features. These are modules of features that are not necessarily correlated, but nevertheless exhibit common function in their... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: James C. Mathews, Saad Nadeem, Maryam Pouryahya, Zehor Belkhatir, Joseph O. Deasy, Arnold J. Levine, Allen R. Tannenbaum Tags: Biological Sciences Source Type: research

Pharmacological disruption of the Notch transcription factor complex [Applied Biological Sciences]
Notch pathway signaling is implicated in several human cancers. Aberrant activation and mutations of Notch signaling components are linked to tumor initiation, maintenance, and resistance to cancer therapy. Several strategies, such as monoclonal antibodies against Notch ligands and receptors, as well as small-molecule γ-secretase inhibitors (GSIs), have been developed to... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: Raȷwinder Lehal, Jelena Zaric, Michele Vigolo, Charlotte Urech, Viktoras Frismantas, Nadine Zangger, Linlin Cao, Adeline Berger, Irene Chicote, Sylvain Loubery, Sung Hee Choi, Ute Koch, Stephen C. Blacklow, Hector G. Palmer, Beat Bornhauser, Marcos Tags: Biological Sciences Source Type: research

Lower bounds to eigenvalues of the Schrodinger equation by solution of a 90-y challenge [Chemistry]
The Ritz upper bound to eigenvalues of Hermitian operators is essential for many applications in science. It is a staple of quantum chemistry and physics computations. The lower bound devised by Temple in 1928 [G. Temple, Proc. R. Soc. A Math. Phys. Eng. Sci. 119, 276–293 (1928)] is not, since... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: Rocco Martinazzo, Eli Pollak Tags: Physical Sciences Source Type: research

Template-stabilized oxidic nickel oxygen evolution catalysts [Chemistry]
Earth-abundant oxygen evolution catalysts (OECs) with extended stability in acid can be constructed by embedding active sites within an acid-stable metal-oxide framework. Here, we report stable NiPbOx films that are able to perform oxygen evolution reaction (OER) catalysis for extended periods of operation (>20 h) in acidic solutions of pH... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: Nancy Li, Thomas P. Keane, Samuel S. Veroneau, Ryan G. Hadt, Dugan Hayes, Lin X. Chen, Daniel G. Nocera Tags: Physical Sciences Source Type: research

On the enigmatic disappearance of Rauber’s layer [Developmental Biology]
The polar trophoblast overlays the epiblast in eutherian mammals and, depending on the species, has one of two different fates. It either remains a single-layered, thinning epithelium called “Rauber’s layer,” which soon disintegrates, or, alternatively, it keeps proliferating, contributing heavily to the population of differentiating, invasive trophoblast cells and, at... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: Jessica van Leeuwen, Pisana Rawson, Debra K. Berg, David N. Wells, Peter L. Pfeffer Tags: Biological Sciences Source Type: research

Multiple transpolar auroral arcs reveal insight about coupling processes in the Earth’s magnetotail [Earth, Atmospheric, and Planetary Sciences]
A distinct class of aurora, called transpolar auroral arc (TPA) (in some cases called “theta” aurora), appears in the extremely high-latitude ionosphere of the Earth when interplanetary magnetic field (IMF) is northward. The formation and evolution of TPA offers clues about processes transferring energy and momentum from the solar wind... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: Qing–He Zhang, Yong–Liang Zhang, Chi Wang, Michael Lockwood, Hui–Gen Yang, Bin–Bin Tang, Zan–Yang Xing, Kȷellmar Oksavik, Larry R. Lyons, Yu–Zhang Ma, Qiu–Gang Zong, Joran Idar Moen, Li–Dong Xia Tags: Physical Sciences Source Type: research

Ethnolinguistic diversity and urban agglomeration [Economic Sciences]
This article shows that higher ethnolinguistic diversity is associated with a greater risk of social tensions and conflict, which, in turn, is a dispersion force lowering urbanization and the incentives to move to big cities. We construct a worldwide dataset at a fine-grained level on urban settlement patterns and ethnolinguistic... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: Ulrich J. Eberle, J. Vernon Henderson, Dominic Rohner, Kurt Schmidheiny Tags: Social Sciences Source Type: research

Unusual activated processes controlling dislocation motion in body-centered-cubic high-entropy alloys [Engineering]
Atomistic simulations of dislocation mobility reveal that body-centered cubic (BCC) high-entropy alloys (HEAs) are distinctly different from traditional BCC metals. HEAs are concentrated solutions in which composition fluctuation is almost inevitable. The resultant inhomogeneities, while locally promoting kink nucleation on screw dislocations, trap them against propagation with an appreciable energy... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: Bing Chen, Suzhi Li, Hongxiang Zong, Xiangdong Ding, Jun Sun, Evan Ma Tags: Physical Sciences Source Type: research

Dynamics of electrohydraulic soft actuators [Engineering]
Nature has inspired the design of robots in which soft actuators enable tasks such as handling of fragile objects and adapting to unstructured environments. Those tasks are difficult for traditional robots, which predominantly consist of hard components. Electrohydraulic soft actuators are liquid-filled shells that deform upon the application of electric... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: Philipp Rothemund, Sophie Kirkman, Christoph Keplinger Tags: Physical Sciences Source Type: research

Direct evidence of poison-driven widespread population decline in a wild vertebrate [Environmental Sciences]
Toxicants such as organochlorine insecticides, lead ammunition, and veterinary drugs have caused severe wildlife poisoning, pushing the populations of several apex species to the edge of extinction. These prime cases epitomize the serious threat that wildlife poisoning poses to biodiversity. Much of the evidence on population effects of wildlife poisoning... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: Patricia Mateo–Tomas, Pedro P. Olea, Eva Minguez, Rafael Mateo, Javier Vinuela Tags: Biological Sciences Source Type: research

Convergent evolution of conserved mitochondrial pathways underlies repeated adaptation to extreme environments [Evolution]
Extreme environments test the limits of life; yet, some organisms thrive in harsh conditions. Extremophile lineages inspire questions about how organisms can tolerate physiochemical stressors and whether the repeated colonization of extreme environments is facilitated by predictable and repeatable evolutionary innovations. We identified the mechanistic basis underlying convergent evolution of... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: Ryan Greenway, Nick Barts, Chathurika Henpita, Anthony P. Brown, Lenin Arias Rodriguez, Carlos M. Rodriguez Pena, Sabine Arndt, Gigi Y. Lau, Michael P. Murphy, Lei Wu, Dingbo Lin, Michael Tobler, Joanna L. Kelley, Jennifer H. Shaw Tags: Biological Sciences Source Type: research

A demographic and evolutionary analysis of maternal effect senescence [Evolution]
Maternal effect senescence—a decline in offspring survival or fertility with maternal age—has been demonstrated in many taxa, including humans. Despite decades of phenotypic studies, questions remain about how maternal effect senescence impacts evolutionary fitness. To understand the influence of maternal effect senescence on population dynamics, fitness, and selection, we developed... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: Christina M. Hernandez, Silke F. van Daalen, Hal Caswell, Michael G. Neubert, Kristin E. Gribble Tags: Biological Sciences Source Type: research

Divergence of chemosensing during the early stages of speciation [Evolution]
Chemosensory communication is essential to insect biology, playing indispensable roles during mate-finding, foraging, and oviposition behaviors. These traits are particularly important during speciation, where chemical perception may serve to establish species barriers. However, identifying genes associated with such complex behavioral traits remains a significant challenge. Through a combination of transcriptomic... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: Bas van Schooten, Jesyka Melendez–Rosa, Steven M. Van Belleghem, Chris D. Jiggins, John D. Tan, W. Owen McMillan, Riccardo Papa Tags: Biological Sciences Source Type: research

MSH1 is required for maintenance of the low mutation rates in plant mitochondrial and plastid genomes [Genetics]
Mitochondrial and plastid genomes in land plants exhibit some of the slowest rates of sequence evolution observed in any eukaryotic genome, suggesting an exceptional ability to prevent or correct mutations. However, the mechanisms responsible for this extreme fidelity remain unclear. We tested seven candidate genes involved in cytoplasmic DNA replication,... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: Zhiqiang Wu, Gus Waneka, Amanda K. Broz, Connor R. King, Daniel B. Sloan Tags: Biological Sciences Source Type: research

Premature termination codons in the DMD gene cause reduced local mRNA synthesis [Genetics]
Duchenne muscular dystrophy (DMD) is caused by mutations in the DMD gene leading to the presence of premature termination codons (PTC). Previous transcriptional studies have shown reduced DMD transcript levels in DMD patient and animal model muscles when PTC are present. Nonsense-mediated decay (NMD) has been suggested to be responsible... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: Raquel Garcia–Rodriguez, Monika Hiller, Laura Jimenez–Gracia, Zarah van der Pal, Judit Balog, Kevin Adamzek, Annemieke Aartsma–Rus, Pietro Spitali Tags: Biological Sciences Source Type: research

The transition to family caregiving and its effect on biomarkers of inflammation [Immunology and Inflammation]
Chronic stress has been widely proposed to increase systemic inflammation, a pathway that may link stress with a heightened risk for many diseases. The chronic stress–inflammation relationship has been challenging to study in humans, however, and family caregiving has been identified as one type of stressful situation that might lead... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: David L. Roth, William E. Haley, Orla C. Sheehan, Jin Huang, J. David Rhodes, Peter Durda, Virginia J. Howard, Jeremy D. Walston, Mary Cushman Tags: Social Sciences Source Type: research

Immunity to commensal skin fungi promotes psoriasiform skin inflammation [Immunology and Inflammation]
Under steady-state conditions, the immune system is poised to sense and respond to the microbiota. As such, immunity to the microbiota, including T cell responses, is expected to precede any inflammatory trigger. How this pool of preformed microbiota-specific T cells contributes to tissue pathologies remains unclear. Here, using an experimental... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: Charlotte Hurabielle, Verena M. Link, Nicolas Bouladoux, Seong-Ji Han, Eric Dean Merrill, Yaima L. Lightfoot, Nickie Seto, Christopher K. E. Bleck, Margery Smelkinson, Oliver J. Harrison, Jonathan L. Linehan, Samira Tamoutounour, Michail S. Lionakis, Mari Tags: Biological Sciences Source Type: research

IL-38 inhibits microglial inflammatory mediators and is decreased in amygdala of children with autism spectrum disorder [Immunology and Inflammation]
Autism spectrum disorder (ASD) is characterized by impaired social interactions and communication. The pathogenesis of ASD is not known, but it involves activation of microglia. We had shown that the peptide neurotensin (NT) is increased in the serum of children with ASD and stimulates cultured adult human microglia to secrete... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: Irene Tsilioni, Harry Pantazopoulos, Pio Conti, Susan E. Leeman, Theoharis C. Theoharides Tags: Biological Sciences Source Type: research

Sex differences in neutrophil biology modulate response to type I interferons and immunometabolism [Immunology and Inflammation]
Differences between female and male immunity may contribute to variations in response to infections and predisposition to autoimmunity. We previously reported that neutrophils from reproductive-age males are more immature and less activated than their female counterparts. To further characterize the mechanisms that drive differential neutrophil phenotypes, we performed RNA sequencing... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: Sarthak Gupta, Shuichiro Nakabo, Luz P. Blanco, Liam J. O’Neil, Gustaf Wigerblad, Rishi R. Goel, Pragnesh Mistry, Kan Jiang, Carmelo Carmona–Rivera, Diana W. Chan, Xinghao Wang, Hege L. Pedersen, Manasi Gadkari, Katherine N. Howe, Faiza Naz, Tags: Biological Sciences Source Type: research

Opinion: What models can and cannot tell us about COVID-19 [Mathematics]
The coronavirus disease 2019 (COVID-19) pandemic, caused by the novel coronavirus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has already claimed more than 470,000 deaths worldwide at the time of this writing (1) and is likely to claim many more. Models can help us determine how to stop the spread... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: Alexander F. Siegenfeld, Nassim N. Taleb, Yaneer Bar-Yam Tags: Opinions, Mathematics, Medical Sciences Source Type: research

Oral squamous cell carcinoma diagnosed from saliva metabolic profiling [Medical Sciences]
Saliva is a noninvasive biofluid that can contain metabolite signatures of oral squamous cell carcinoma (OSCC). Conductive polymer spray ionization mass spectrometry (CPSI-MS) is employed to record a wide range of metabolite species within a few seconds, making this technique appealing as a point-of-care method for the early detection of... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: Xiaowei Song, Xihu Yang, Rahul Narayanan, Vishnu Shankar, Sathiyaraj Ethiraj, Xiang Wang, Ning Duan, Yan-Hong Ni, Qingang Hu, Richard N. Zare Tags: Physical Sciences Source Type: research

JNK-mediated disruption of bile acid homeostasis promotes intrahepatic cholangiocarcinoma [Medical Sciences]
Metabolic stress causes activation of the cJun NH2-terminal kinase (JNK) signal transduction pathway. It is established that one consequence of JNK activation is the development of insulin resistance and hepatic steatosis through inhibition of the transcription factor PPARα. Indeed, JNK1/2 deficiency in hepatocytes protects against the development of steatosis, suggesting... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: Elisa Manieri, Cintia Folgueira, Maria Elena Rodriguez, Luis Leiva–Vega, Laura Esteban–Lafuente, Chaobo Chen, Francisco Javier Cubero, Tamera Barrett, Julie Cavanagh–Kyros, Davide Seruggia, Aleȷandro Rosell, Fatima Sanchez–C Tags: Biological Sciences Source Type: research

Fibroblast-tumor cell signaling limits HER2 kinase therapy response via activation of MTOR and antiapoptotic pathways [Medical Sciences]
Despite the implementation of multiple HER2-targeted therapies, patients with advanced HER2+ breast cancer ultimately develop drug resistance. Stromal fibroblasts represent an abundant cell type in the tumor microenvironment and have been linked to poor outcomes and drug resistance. Here, we show that fibroblasts counteract the cytotoxic effects of HER2 kinase-targeted... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: Ioannis K. Zervantonakis, Matthew D. Poskus, Alexis L. Scott, Laura M. Selfors, Jia-Ren Lin, Deborah A. Dillon, Shailja Pathania, Peter K. Sorger, Gordon B. Mills, Joan S. Brugge Tags: Biological Sciences Source Type: research

Inhibition of DUX4 expression with antisense LNA gapmers as a therapy for facioscapulohumeral muscular dystrophy [Medical Sciences]
Facioscapulohumeral muscular dystrophy (FSHD), characterized by progressive muscle weakness and deterioration, is genetically linked to aberrant expression of DUX4 in muscle. DUX4, in its full-length form, is cytotoxic in nongermline tissues. Here, we designed locked nucleic acid (LNA) gapmer antisense oligonucleotides (AOs) to knock down DUX4 in immortalized FSHD myoblasts... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: Kenji Rowel Q. Lim, Rika Maruyama, Yusuke Echigoya, Quynh Nguyen, Aiping Zhang, Hunain Khawaja, Sreetama Sen Chandra, Takako Jones, Peter Jones, Yi-Wen Chen, Toshifumi Yokota Tags: Biological Sciences Source Type: research

LIN28B regulates transcription and potentiates MYCN-induced neuroblastoma through binding to ZNF143 at target gene promotors [Medical Sciences]
LIN28B is highly expressed in neuroblastoma and promotes tumorigenesis, at least, in part, through inhibition of let-7 microRNA biogenesis. Here, we report that overexpression of either wild-type (WT) LIN28B or a LIN28B mutant that is unable to inhibit let-7 processing increases the penetrance of MYCN-induced neuroblastoma, potentiates the invasion and... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: Ting Tao, Hui Shi, Luca Mariani, Brian J. Abraham, Adam D. Durbin, Mark W. Zimmerman, John T. Powers, Pavlos Missios, Kenneth N. Ross, Antonio R. Perez-Atayde, Martha L. Bulyk, Richard A. Young, George Q. Daley, A. Thomas Look Tags: Biological Sciences Source Type: research

Folate stress induces SLX1- and RAD51-dependent mitotic DNA synthesis at the fragile X locus in human cells [Medical Sciences]
Folate deprivation drives the instability of a group of rare fragile sites (RFSs) characterized by CGG trinucleotide repeat (TNR) sequences. Pathological expansion of the TNR within the FRAXA locus perturbs DNA replication and is the major causative factor for fragile X syndrome, a sex-linked disorder associated with cognitive impairment. Although... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: Lorenza Garribba, Victoria A. Bȷerregaard, Marisa M. Goncalves Dinis, Ozgun Ozer, Wei Wu, Despoina Sakellariou, Javier Pena–Diaz, Ian D. Hickson, Ying Liu Tags: Biological Sciences Source Type: research

Using synthetic biology to overcome barriers to stable expression of nitrogenase in eukaryotic organelles [Microbiology]
Engineering biological nitrogen fixation in eukaryotic cells by direct introduction of nif genes requires elegant synthetic biology approaches to ensure that components required for the biosynthesis of active nitrogenase are stable and expressed in the appropriate stoichiometry. Previously, the NifD subunits of nitrogenase MoFe protein from Azotobacter vinelandii and Klebsiella... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: Nan Xiang, Chenyue Guo, Jiwei Liu, Hao Xu, Ray Dixon, Jianguo Yang, Yi-Ping Wang Tags: Biological Sciences Source Type: research

A lipocalin mediates unidirectional heme biomineralization in malaria parasites [Microbiology]
During blood-stage development, malaria parasites are challenged with the detoxification of enormous amounts of heme released during the proteolytic catabolism of erythrocytic hemoglobin. They tackle this problem by sequestering heme into bioinert crystals known as hemozoin. The mechanisms underlying this biomineralization process remain enigmatic. Here, we demonstrate that both rodent... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: Joachim M. Matz, Benjamin Drepper, Thorsten B. Blum, Eric van Genderen, Alana Burrell, Peer Martin, Thomas Stach, Lucy M. Collinson, Jan Pieter Abrahams, Kai Matuschewski, Michael J. Blackman Tags: Biological Sciences Source Type: research

Dissecting the mechanism of signaling-triggered nuclear export of newly synthesized influenza virus ribonucleoprotein complexes [Microbiology]
Influenza viruses (IV) exploit a variety of signaling pathways. Previous studies showed that the rapidly accelerated fibrosarcoma/mitogen-activated protein kinase/extracellular signal-regulated kinase (Raf/MEK/ERK) pathway is functionally linked to nuclear export of viral ribonucleoprotein (vRNP) complexes, suggesting that vRNP export is a signaling-induced event. However, the underlying mechanism remained completely enigmatic. Here... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: Andre Schreiber, Laurita Boff, Darisuren Anhlan, Tim Krischuns, Linda Brunotte, Christian Schuberth, Roland Wedlich–Soldner, Hannes Drexler, Stephan Ludwig Tags: Biological Sciences Source Type: research

The E3 ubiquitin ligase MARCH1 regulates antimalaria immunity through interferon signaling and T cell activation [Microbiology]
Malaria infection induces complex and diverse immune responses. To elucidate the mechanisms underlying host–parasite interaction, we performed a genetic screen during early (24 h) Plasmodium yoelii infection in mice and identified a large number of interacting host and parasite genes/loci after transspecies expression quantitative trait locus (Ts-eQTL) analysis. We next... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: Jian Wu, Lu Xia, Xiangyu Yao, Xiao Yu, Keyla C. Tumas, Wenxiang Sun, Yang Cheng, Xiao He, Yu-chih Peng, Brajesh K. Singh, Cui Zhang, Chen-Feng Qi, Silvia Bolland, Sonja M. Best, Channe Gowda, Ruili Huang, Timothy G. Myers, Carole A. Long, Rong-Fu Wang, Xi Tags: Biological Sciences Source Type: research

Yaravirus: A novel 80-nm virus infecting Acanthamoeba castellanii [Microbiology]
Here we report the discovery of Yaravirus, a lineage of amoebal virus with a puzzling origin and evolution. Yaravirus presents 80-nm-sized particles and a 44,924-bp dsDNA genome encoding for 74 predicted proteins. Yaravirus genome annotation showed that none of its genes matched with sequences of known organisms at the nucleotide... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: Paulo V. M. Boratto, Graziele P. Oliveira, Talita B. Machado, Ana Claudia S. P. Andrade, Jean–Pierre Baudoin, Thomas Klose, Frederik Schulz, Said Azza, Philippe Decloquement, Eric Chabriere, Philippe Colson, Anthony Levasseur, Bernard La Scola, Jona Tags: Biological Sciences Source Type: research

Syrian hamsters as a small animal model for SARS-CoV-2 infection and countermeasure development [Microbiology]
At the end of 2019, a novel coronavirus (severe acute respiratory syndrome coronavirus 2; SARS-CoV-2) was detected in Wuhan, China, that spread rapidly around the world, with severe consequences for human health and the global economy. Here, we assessed the replicative ability and pathogenesis of SARS-CoV-2 isolates in Syrian hamsters.... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: Masaki Imai, Kiyoko Iwatsuki-Horimoto, Masato Hatta, Samantha Loeber, Peter J. Halfmann, Noriko Nakajima, Tokiko Watanabe, Michiko Ujie, Kenta Takahashi, Mutsumi Ito, Shinya Yamada, Shufang Fan, Shiho Chiba, Makoto Kuroda, Lizheng Guan, Kosuke Takada, Tam Tags: Coronavirus (COVID-19) Biological Sciences Source Type: research

Core Concept: How synaptic pruning shapes neural wiring during development and, possibly, in disease [Neuroscience]
At birth, an infant’s brain is packed with roughly 100 billion neurons—some 15% more than it will have as an adult. As we learn and grow, our experiences strengthen the circuits that prove most relevant while the others weaken and fade. Nerve cells in the cerebellum called purkinje cells (blue)... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 14, 2020 Category: Science Authors: Jill Sakai Tags: Core Concepts, Neuroscience Source Type: research