Correction for Kalogriopoulos et al., Structural basis for GPCR-independent activation of heterotrimeric Gi proteins [Correction]
BIOPHYSICS AND COMPUTATIONAL BIOLOGY Correction for “Structural basis for GPCR-independent activation of heterotrimeric Gi proteins,” by Nicholas A. Kalogriopoulos, Steven D. Rees, Tony Ngo, Noah J. Kopcho, Andrey V. Ilatovskiy, Nina Sun, Elizabeth A. Komives, Geoffrey Chang, Pradipta Ghosh, and Irina Kufareva, which was first published July 30, 2019; 10.1073/pnas.1906658116... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Tags: Corrections Source Type: research

Retraction for Bearzi et al., Identification of a coronary vascular progenitor cell in the human heart [Retraction]
MEDICAL SCIENCES Retraction for “Identification of a coronary vascular progenitor cell in the human heart,” by Claudia Bearzi, Annarosa Leri, Francesco Lo Monaco, Marcello Rota, Arantxa Gonzalez, Toru Hosoda, Martino Pepe, Khaled Qanud, Caroline Ojaimi, Silvana Bardelli, Domenico D’Amario, David A. D’Alessandro, Robert E. Michler, Stefanie Dimmeler, Andreas M. Zeiher,... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Tags: Retractions Source Type: research

Retraction for Boni et al., Notch1 regulates the fate of cardiac progenitor cells [Retraction]
MEDICAL SCIENCES Retraction for “Notch1 regulates the fate of cardiac progenitor cells,” by Alessandro Boni, Konrad Urbanek, Angelo Nascimbene, Toru Hosoda, Hanqiao Zheng, Francesca Delucchi, Katsuya Amano, Arantxa Gonzalez, Serena Vitale, Caroline Ojaimi, Roberto Rizzi, Roberto Bolli, Katherine E. Yutzey, Marcello Rota, Jan Kajstura, Piero Anversa, and Annarosa Leri, which... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Tags: Retractions Source Type: research

Magnetic field-driven quantum criticality in antiferromagnetic CePtIn4 [Physics]
We present comprehensive experimental evidence of a magnetic field-tuned tricritical point separating paramagnetic, antiferromagnetic, and metamagnetic... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Authors: Debarchan Das, Daniel Gnida, Piotr Wiśniewski, Dariusz Kaczorowski Tags: Physical Sciences Source Type: research

Generation and detection of spin-orbit coupled neutron beams [Physics]
Spin-orbit coupling of light has come to the fore in nanooptics and plasmonics, and is a key ingredient of topological photonics and chiral quantum optics. We demonstrate a basic tool for incorporating analogous effects into neutron optics: the generation and detection of neutron beams with coupled spin and orbital angular... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Authors: Dusan Sarenac, Connor Kapahi, Wangchun Chen, Charles W. Clark, David G. Cory, Michael G. Huber, Ivar Taminiau, Kirill Zhernenkov, Dmitry A. Pushin Tags: Physical Sciences Source Type: research

Raman interrogation of the ferroelectric phase transition in polar metal LiOsO3 [Physics]
Ferroelectric (FE) distortions in a metallic material were believed to be experimentally inaccessible because itinerant electrons would screen the long-range Coulomb interactions that favor a polar structure. It has been suggested by Anderson and Blount [P. W. Anderson, E. I. Blount, Phys. Rev. Lett. 14, 217−219 (1965)] that a transition... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Authors: Feng Jin, Le Wang, Anmin Zhang, Jianting Ji, Youguo Shi, Xiaoqun Wang, Rong Yu, Jiandi Zhang, E. W. Plummer, Qingming Zhang Tags: Physical Sciences Source Type: research

The NMDA receptor activation by d-serine and glycine is controlled by an astrocytic Phgdh-dependent serine shuttle [Neuroscience]
Astrocytes express the 3-phosphoglycerate dehydrogenase (Phgdh) enzyme required for the synthesis of l-serine from glucose. Astrocytic l-serine was proposed to regulate NMDAR activity by shuttling to neurons to sustain d-serine production, but this hypothesis remains untested. We now report that inhibition of astrocytic Phgdh suppressed the de novo synthesis of... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Authors: Samah Neame, Hazem Safory, Inna Radzishevsky, Ayelet Touitou, Francesco Marchesani, Marialaura Marchetti, Shai Kellner, Shai Berlin, Veronika N. Foltyn, Simone Engelender, Jean-Marie Billard, Herman Wolosker Tags: Biological Sciences Source Type: research

A Tmc1 mutation reduces calcium permeability and expression of mechanoelectrical transduction channels in cochlear hair cells [Neuroscience]
Mechanoelectrical transducer (MET) currents were recorded from cochlear hair cells in mice with mutations of transmembrane channel-like protein TMC1 to study the effects on MET channel properties. We characterized a Tmc1 mouse with a single-amino-acid mutation (D569N), homologous to a dominant human deafness mutation. Measurements were made in both Tmc2... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Authors: Maryline Beurg, Amanda Barlow, David N. Furness, Robert Fettiplace Tags: Biological Sciences Source Type: research

Structural and functional analyses reveal promiscuous and species specific use of ephrin receptors by Cedar virus [Microbiology]
Cedar virus (CedV) is a bat-borne henipavirus related to Nipah virus (NiV) and Hendra virus (HeV), zoonotic agents of fatal human disease. CedV receptor-binding protein (G) shares only ∼30% sequence identity with those of NiV and HeV, although they can all use ephrin-B2 as an entry receptor. We demonstrate that... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Authors: Eric D. Laing, Chanakha K. Navaratnarajah, Sofia Cheliout Da Silva, Stephanie R. Petzing, Yan Xu, Spencer L. Sterling, Glenn A. Marsh, Lin-Fa Wang, Moushimi Amaya, Dimitar B. Nikolov, Roberto Cattaneo, Christopher C. Broder, Kai Xu Tags: Biological Sciences Source Type: research

NanoSIMS imaging reveals metabolic stratification within current-producing biofilms [Microbiology]
Metal-reducing bacteria direct electrons to their outer surfaces, where insoluble metal oxides or electrodes act as terminal electron acceptors, generating electrical current from anaerobic respiration. Geobacter sulfurreducens is a commonly enriched electricity-producing organism, forming thick conductive biofilms that magnify total activity by supporting respiration of cells not in direct contact... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Authors: Grayson L. Chadwick, Fernanda Jimenez Otero, Jeffrey A. Gralnick, Daniel R. Bond, Victoria J. Orphan Tags: Biological Sciences Source Type: research

Predicting kidney transplant outcomes with partial knowledge of HLA mismatch [Medical Sciences]
We consider prediction of graft survival when a kidney from a deceased donor is transplanted into a recipient, with a focus on the variation of survival with degree of human leukocyte antigen (HLA) mismatch. Previous studies have used data from the Scientific Registry of Transplant Recipients (SRTR) to predict survival... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Authors: Charles F. Manski, Anat R. Tambur, Michael Gmeiner Tags: Social Sciences Source Type: research

Preclinical murine platform to evaluate therapeutic countermeasures against radiation-induced gastrointestinal syndrome [Medical Sciences]
In this study, we developed an in vivo mouse-modeling platform that enables spatial and temporal manipulation of potential... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Authors: Paul B. Romesser, Amanda S. Kim, Jeho Jeong, Allison Mayle, Lukas E. Dow, Scott W. Lowe Tags: Biological Sciences Source Type: research

Immunization against poly-N-acetylglucosamine reduces neutrophil activation and GVHD while sparing microbial diversity [Microbiology]
Microbial invasion into the intestinal mucosa after allogeneic hematopoietic cell transplantation (allo-HCT) triggers neutrophil activation and requires antibiotic interventions to prevent sepsis. However, antibiotics lead to a loss of microbiota diversity, which is connected to a higher incidence of acute graft-versus-host disease (aGVHD). Antimicrobial therapies that eliminate invading bacteria and... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Authors: Jan Hulsdunker, Oliver S. Thomas, Eileen Haring, Susanne Unger, Nicolas Gonzalo Nunez, Sonia Tugues, Zhan Gao, Sandra Duquesne, Colette Cywes–Bentley, Ozlem Oyardi, Susanne Kirschnek, Annette Schmitt–Graeff, Oliver Pabst, Christian Koenecke, J Tags: Biological Sciences Source Type: research

Inhibition of {Delta}24-dehydrocholesterol reductase activates pro-resolving lipid mediator biosynthesis and inflammation resolution [Immunology and Inflammation]
Targeting metabolism through bioactive key metabolites is an upcoming future therapeutic strategy. We questioned how modifying intracellular lipid metabolism could be a possible means for alleviating inflammation. Using a recently developed chemical probe (SH42), we inhibited distal cholesterol biosynthesis through selective inhibition of Δ24-dehydrocholesterol reductase (DHCR24). Inhibition of DHCR24 led... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Authors: Andreas Korner, Enchen Zhou, Christoph Muller, Yassene Mohammed, Sandra Herceg, Franz Bracher, Patrick C. N. Rensen, Yanan Wang, Valbona Mirakaȷ, Martin Giera Tags: Biological Sciences Source Type: research

The role of multilevel selection in host microbiome evolution [Evolution]
Animals are associated with a microbiome that can affect their reproductive success. It is, therefore, important to understand how a host and its microbiome coevolve. According to the hologenome concept, hosts and their microbiome form an integrated evolutionary entity, a holobiont, on which selection can potentially act directly. However, this... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Authors: Simon van Vliet, Michael Doebeli Tags: Biological Sciences Source Type: research

Experimental evolution of immunological specificity [Evolution]
Memory and specificity are hallmarks of the adaptive immune system. Contrary to prior belief, innate immune systems can also provide forms of immune memory, such as immune priming in invertebrates and trained immunity in vertebrates. Immune priming can even be specific but differs remarkably in cellular and molecular functionality from... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Authors: Kevin Ferro, Robert Peuss, Wentao Yang, Philip Rosenstiel, Hinrich Schulenburg, Joachim Kurtz Tags: Biological Sciences Source Type: research

The nucleosome core particle remembers its position through DNA replication and RNA transcription [Genetics]
Nucleosomes are the fundamental structural unit of chromatin. In addition to stabilizing the DNA polymer, nucleosomes are modified in ways that reflect and affect gene expression in their vicinity. It has long been assumed that nucleosomes can transmit memory of gene expression through their covalent posttranslational modifications. An unproven assumption... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Authors: Gavin Schlissel, Jasper Rine Tags: Biological Sciences Source Type: research

Climate cooling and clade competition likely drove the decline of lamniform sharks [Evolution]
Understanding heterogeneity in species richness between closely related clades is a key research question in ecology and evolutionary biology. Multiple hypotheses have been proposed to interpret such diversity contrasts across the tree of life, with most studies focusing on speciation rates to explain clades’ evolutionary radiations, while often neglecting extinction... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Authors: Fabien L. Condamine, Jules Romieu, Guillaume Guinot Tags: Biological Sciences Source Type: research

An experimental test of the ovulatory homolog model of female orgasm [Evolution]
The ovulatory homolog model of female orgasm posits that the neuro-endocrine mechanisms underlying female orgasm evolved from and are homologous to the mechanisms mediating copulation-induced ovulation in some mammals. This model predicts that pharmacological agents that affect human orgasm, such as fluoxetine, should also affect ovulation in animals with copulation-induced... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Authors: Mihaela Pavlicev, Andreȷa Moset Zupan, Amanda Barry, Savannah Walters, Kristin M. Milano, Harvey J. Kliman, Gunter P. Wagner Tags: Inaugural Articles Biological Sciences Source Type: research

A marine plasmid hitchhiking vast phylogenetic and geographic distances [Environmental Sciences]
Horizontal gene transfer (HGT) plays an important role in bacterial evolution and serves as a driving force for bacterial diversity and versatility. HGT events often involve mobile genetic elements like plasmids, which can promote their own dissemination by associating with adaptive traits in the gene pool of the so-called mobilome.... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Authors: Jorn Petersen, John Vollmers, Victoria Ringel, Henner Brinkmann, Claire Ellebrandt–Sperling, Cathrin Sproer, Alexandra M. Howat, J. Colin Murrell, Anne–Kristin Kaster Tags: Biological Sciences Source Type: research

News Feature: Fighting a fungal scourge [Environmental Sciences]
Researchers trying to rescue amphibians from a global fungus epidemic are finding that bacteria may be their best allies. More than a decade ago, amphibian microbial ecologist Reid Harris watched a mother salamander as she marched in a figure-eight pattern through her clutch of soft, jellylike eggs. He knew that... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Authors: Amy McDermott Tags: News Features, Front Matter Source Type: research

Variable impacts of contemporary versus legacy agricultural phosphorus on US river water quality [Environmental Sciences]
Phosphorus (P) fertilizer has contributed to the eutrophication of freshwater ecosystems. Watershed-based conservation programs aiming to reduce external P loading to surface waters have not resulted in significant water-quality improvements. One factor that can help explain the lack of water-quality response is remobilization of accumulated legacy (historical) P within the... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Authors: Sarah M. Stackpoole, Edward G. Stets, Lori A. Sprague Tags: Biological Sciences Source Type: research

Individual and collective encoding of risk in animal groups [Ecology]
The need to make fast decisions under risky and uncertain conditions is a widespread problem in the natural world. While there has been extensive work on how individual organisms dynamically modify their behavior to respond appropriately to changing environmental conditions (and how this is encoded in the brain), we know... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Authors: Matthew M. G. Sosna, Colin R. Twomey, Joseph Bak-Coleman, Winnie Poel, Bryan C. Daniels, Pawel Romanczuk, Iain D. Couzin Tags: Biological Sciences Source Type: research

Ca isotopes record rapid crystal growth in volcanic and subvolcanic systems [Earth, Atmospheric, and Planetary Sciences]
Kinetic calcium isotope effects can be used as growth-rate proxies for volcanic and subvolcanic minerals. Here, we analyze Ca isotopic compositions in experimental and natural samples and confirm that large kinetic effects (>2‰) can occur during magmatic plagioclase crystallization. Experiments confirm theoretical predictions that disequilibrium isotope effects depend mainly on... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Authors: Michael A. Antonelli, Tushar Mittal, Anders McCarthy, Barbara Tripoli, James M. Watkins, Donald J. DePaolo Tags: Physical Sciences Source Type: research

Factors driving the seasonal and hourly variability of sea-spray aerosol number in the North Atlantic [Earth, Atmospheric, and Planetary Sciences]
Four North Atlantic Aerosol and Marine Ecosystems Study (NAAMES) field campaigns from winter 2015 through spring 2018 sampled an extensive set of oceanographic and atmospheric parameters during the annual phytoplankton bloom cycle. This unique dataset provides four seasons of open-ocean observations of wind speed, sea surface temperature (SST), seawater particle... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Authors: Georges Saliba, Chia–Li Chen, Savannah Lewis, Lynn M. Russell, Laura–Helena Rivellini, Alex K. Y. Lee, Patricia K. Quinn, Timothy S. Bates, Nils Haentȷens, Emmanuel S. Boss, Lee Karp–Boss, Nicholas Baetge, Craig A. Carlson, Michae Tags: Physical Sciences Source Type: research

Early detection and monitoring of cerebral ischemia using calcium-responsive MRI probes [Chemistry]
We present a methodology for fast detection and real-time monitoring of fluctuations of calcium ions associated with focal ischemia using a molecular functional MRI... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Authors: Tanȷa Savić, Giuseppe Gambino, Vahid S. Bokharaie, Hamid R. Noori, Nikos K. Logothetis, Goran Angelovski Tags: Biological Sciences Source Type: research

Dronc-independent basal executioner caspase activity sustains Drosophila imaginal tissue growth [Developmental Biology]
Caspase is best known as an enzyme involved in programmed cell death, which is conserved among multicellular organisms. In addition to its role in cell death, caspase is emerging as an indispensable enzyme in a wide range of cellular functions, which have recently been termed caspase-dependent nonlethal cellular processes (CDPs).... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Authors: Natsuki Shinoda, Nozomi Hanawa, Takahiro Chihara, Akiko Koto, Masayuki Miura Tags: Biological Sciences Source Type: research

Selective cadmium regulation mediated by a cooperative binding mechanism in CadR [Chemistry]
Detoxification of the highly toxic cadmium element is essential for the survival of living organisms. Pseudomonas putida CadR, a MerR family transcriptional regulator, has been reported to exhibit an ultraspecific response to the cadmium ion. Our crystallographic and spectroscopic studies reveal that the extra cadmium selectivity of CadR is mediated... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Authors: Xichun Liu, Qingyuan Hu, Jinmei Yang, Shanqing Huang, Tianbiao Wei, Weizhong Chen, Yafeng He, Dan Wang, Zhijun Liu, Kang Wang, Jianhua Gan, Hao Chen Tags: Biological Sciences Source Type: research

Excited-state proton transfer relieves antiaromaticity in molecules [Chemistry]
Baird’s rule explains why and when excited-state proton transfer (ESPT) reactions happen in organic compounds. Bifunctional compounds that are [4n + 2] π-aromatic in the ground state, become [4n + 2] π-antiaromatic in the first 1ππ* states, and proton transfer (either inter- or intramolecularly) helps relieve excited-state antiaromaticity. Computed nucleus-independent... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Authors: Chia–Hua Wu, Lucas Jose Karas, Henrik Ottosson, Judy I–Chia Wu Tags: Physical Sciences Source Type: research

A self-assembled Ru-Pt metallacage as a lysosome-targeting photosensitizer for 2-photon photodynamic therapy [Chemistry]
Photodynamic therapy (PDT) is a treatment procedure that relies on cytotoxic reactive oxygen species (ROS) generated by the light activation of a photosensitizer. The photophysical and biological properties of photosensitizers are vital for the therapeutic outcome of PDT. In this work a 2D rhomboidal metallacycle and a 3D octahedral metallacage... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Authors: Zhixuan Zhou, Jiangping Liu, Juanjuan Huang, Thomas W. Rees, Yiliang Wang, Heng Wang, Xiaopeng Li, Hui Chao, Peter J. Stang Tags: Physical Sciences Source Type: research

Phosphorylation of DEPDC5, a component of the GATOR1 complex, releases inhibition of mTORC1 and promotes tumor growth [Cell Biology]
The Pim and AKT serine/threonine protein kinases are implicated as drivers of cancer. Their regulation of tumor growth is closely tied to the ability of these enzymes to mainly stimulate protein synthesis by activating mTORC1 (mammalian target of rapamycin complex 1) signaling, although the exact mechanism is not completely understood.... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Authors: Sathish K. R. Padi, Neha Singh, Jeremiah J. Bearss, Virginie Olive, Jin H. Song, Marina Cardo–Vila, Andrew S. Kraft, Koichi Okumura Tags: Biological Sciences Source Type: research

CRIF1 as a potential target to improve the radiosensitivity of osteosarcoma [Cell Biology]
Resistance to ionizing radiation (IR), which is a conventional treatment for osteosarcoma that cannot be resected, undermines the efficacy of this therapy. However, the mechanism by which IR induces radioresistance in osteosarcoma is not defined. Here, we report that CR6-interacting factor-1 (CRIF1) is highly expressed in osteosarcoma and undergoes nuclear-cytoplasmic... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Authors: Qian Ran, Feng Jin, Yang Xiang, Lixin Xiang, Qiushi Wang, Fengjie Li, Li Chen, Yuan Zhang, Chun Wu, Luping Zhou, Yanni Xiao, Lili Chen, Jiang Wu, Jiang F. Zhong, Shengwen Calvin Li, Zhongjun Li Tags: Biological Sciences Source Type: research

Mast cells are critical for controlling the bacterial burden and the healing of infected wounds [Cell Biology]
Skin wound infections are a significant health problem, and antibiotic resistance is on the rise. Mast cells (MCs) have been shown to contribute to host–defense responses in certain bacterial infections, but their role in skin wound superinfection is unknown. We subjected 2 MC-deficient mouse strains to Pseudomonas aeruginosa skin wound... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Authors: C. Zimmermann, D. Troeltzsch, V. A. Gimenez–Rivera, S. J. Galli, M. Metz, M. Maurer, F. Siebenhaar Tags: Biological Sciences Source Type: research

Single-molecule localization microscopy as nonlinear inverse problem [Biophysics and Computational Biology]
We describe iterative parameter-estimation algorithms based on this framework, as well as a sampling algorithm to numerically... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Authors: Ji Yu, Ahmed Elmokadem Tags: Biological Sciences Source Type: research

Cell division rates decrease with age, providing a potential explanation for the age-dependent deceleration in cancer incidence [Biophysics and Computational Biology]
A new evaluation of previously published data suggested to us that the accumulation of mutations might slow, rather than increase, as individuals age. To explain this unexpected finding, we hypothesized that normal stem cell division rates might decrease as we age. To test this hypothesis, we evaluated cell division rates... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Authors: Cristian Tomasetti, Justin Poling, Nicholas J. Roberts, Nyall R. London Jr., Meredith E. Pittman, Michael C. Haffner, Anthony Rizzo, Alex Baras, Baktiar Karim, Antonio Kim, Christopher M. Heaphy, Alan K. Meeker, Ralph H. Hruban, Christine A. Iacobuzio-Don Tags: Biological Sciences Source Type: research

The structure of the colorectal cancer-associated enzyme GalNAc-T12 reveals how nonconserved residues dictate its function [Biochemistry]
Polypeptide N-acetylgalactosaminyl transferases (GalNAc-Ts) initiate mucin type O-glycosylation by catalyzing the transfer of N-acetylgalactosamine (GalNAc) to Ser or Thr on a protein substrate. Inactive and partially active variants of the isoenzyme GalNAc-T12 are present in subsets of patients with colorectal cancer, and several of these variants alter nonconserved residues with... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Authors: Amy J. Fernandez, Earnest James Paul Daniel, Sai Pooja Mahajan, Jeffrey J. Gray, Thomas A. Gerken, Lawrence A. Tabak, Nadine L. Samara Tags: Biological Sciences Source Type: research

Epsilon iron as a spin-smectic state [Applied Physical Sciences]
Using X-ray emission spectroscopy, we find appreciable local magnetic moments until 30 GPa to 40 GPa in the high-pressure phase of iron; however, no magnetic order is detected with neutron powder diffraction down to 1.8 K, contrary to previous predictions. Our first-principles calculations reveal a “spin-smectic” state lower in energy... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Authors: Blair W. Lebert, Tommaso Gorni, Michele Casula, Stefan Klotz, Francois Baudelet, James M. Ablett, Thomas C. Hansen, Amelie Juhin, Alain Polian, Pascal Munsch, Gilles Le Marchand, Zailan Zhang, Jean–Pascal Rueff, Matteo d’Astuto Tags: Physical Sciences Source Type: research

Propinquity drives the emergence of network structure and density [Applied Physical Sciences]
The lack of large-scale, continuously evolving empirical data usually limits the study of networks to the analysis of snapshots in time. This approach has been used for verification of network evolution mechanisms, such as preferential attachment. However, these studies are mostly restricted to the analysis of the first links established... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Authors: Lazaros K. Gallos, Shlomo Havlin, H. Eugene Stanley, Nina H. Fefferman Tags: Social Sciences Source Type: research

The making of natural iron sulfide nanoparticles in a hot vent snail [Applied Biological Sciences]
Biomineralization in animals exclusively features oxygen-based minerals with a single exception of the scaly-foot gastropod Chrysomallon squamiferum, the only metazoan with an iron sulfide skeleton. This unique snail inhabits deep-sea hot vents and possesses scales infused with iron sulfide nanoparticles, including pyrite, giving it a characteristic metallic black sheen. Since... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Authors: Satoshi Okada, Chong Chen, Tomo-o Watsuji, Manabu Nishizawa, Yohey Suzuki, Yuji Sano, Dass Bissessur, Shigeru Deguchi, Ken Takai Tags: Biological Sciences Source Type: research

Cryptic diversity of a widespread global pathogen reveals expanded threats to amphibian conservation [Applied Biological Sciences]
Biodiversity loss is one major outcome of human-mediated ecosystem disturbance. One way that humans have triggered wildlife declines is by transporting disease-causing agents to remote areas of the world. Amphibians have been hit particularly hard by disease due in part to a globally distributed pathogenic chytrid fungus (Batrachochytrium dendrobatidis [Bd]).... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Authors: Allison Q. Byrne, Vance T. Vredenburg, An Martel, Frank Pasmans, Rayna C. Bell, David C. Blackburn, Molly C. Bletz, Jaime Bosch, Cheryl J. Briggs, Rafe M. Brown, Alessandro Catenazzi, Mariel Familiar Lopez, Raul Figueroa–Valenzuela, Sonia L. Ghose, Tags: Biological Sciences Source Type: research

Observation of Rydberg exciton polaritons and their condensate in a perovskite cavity [Applied Physical Sciences]
The condensation of half-light half-matter exciton polaritons in semiconductor optical cavities is a striking example of macroscopic quantum coherence in a solid-state platform. Quantum coherence is possible only when there are strong interactions between the exciton polaritons provided by their excitonic constituents. Rydberg excitons with high principal value exhibit strong... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Authors: Wei Bao, Xiaoze Liu, Fei Xue, Fan Zheng, Renjie Tao, Siqi Wang, Yang Xia, Mervin Zhao, Jeongmin Kim, Sui Yang, Quanwei Li, Ying Wang, Yuan Wang, Lin-Wang Wang, Allan H. MacDonald, Xiang Zhang Tags: Physical Sciences Source Type: research

Maize sugary enhancer1 (se1) is a gene affecting endosperm starch metabolism [Plant Biology]
sugary enhancer1 (se1) is a naturally occurring mutant allele involved in starch metabolism in maize endosperm. It is a recessive modifier of sugary1 (su1) and commercially important in modern sweet corn breeding, but its molecular identity and mode of action remain unknown. Here, we developed a pair of near-isogenic lines,... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Authors: Xia Zhang, Karl J. Haro von Mogel, Vai S. Lor, Candice N. Hirsch, Brian De Vries, Heidi F. Kaeppler, William F. Tracy, Shawn M. Kaeppler Tags: PNAS Plus Source Type: research

Highly efficient DSB-free base editing for streptomycetes with CRISPR-BEST [Applied Biological Sciences]
Streptomycetes serve as major producers of various pharmacologically and industrially important natural products. Although CRISPR-Cas9 systems have been developed for more robust genetic manipulations, concerns of genome instability caused by the DNA double-strand breaks (DSBs) and the toxicity of Cas9 remain. To overcome these limitations, here we report development of... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Authors: Yaoȷun Tong, Christopher M. Whitford, Helene L. Robertsen, Kai Blin, Tue S. Jorgensen, Andreas K. Klitgaard, Tetiana Gren, Xinglin Jiang, Tilmann Weber, Sang Yup Lee Tags: Biological Sciences Source Type: research

Cell models of lipid-rich {alpha}-synuclein aggregation validate known modifiers of {alpha}-synuclein biology and identify stearoyl-CoA desaturase [Neuroscience]
Microscopy of Lewy bodies in Parkinson’s disease (PD) suggests they are not solely filamentous deposits of α-synuclein (αS) but also contain vesicles and other membranous material. We previously reported the existence of native αS tetramers/multimers and described engineered mutations of the αS KTKEGV repeat motifs that abrogate the multimers. The... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Authors: Thibaut Imberdis, Joseph Negri, Nagendran Ramalingam, Elizabeth Terry-Kantor, Gary P. H. Ho, Saranna Fanning, Georgia Stirtz, Tae-Eun Kim, Oren A. Levy, Tracy L. Young-Pearse, Dennis Selkoe, Ulf Dettmer Tags: PNAS Plus Source Type: research

Parkinson’s disease-associated iPLA2-VIA/PLA2G6 regulates neuronal functions and {alpha}-synuclein stability through membrane remodeling [Medical Sciences]
Mutations in the iPLA2-VIA/PLA2G6 gene are responsible for PARK14-linked Parkinson’s disease (PD) with α-synucleinopathy. However, it is unclear how iPLA2-VIA mutations lead to α-synuclein (α-Syn) aggregation and dopaminergic (DA) neurodegeneration. Here, we report that iPLA2-VIA–deficient Drosophila exhibits defects in neurotransmission during early developmental stages and progressive cell loss throughout the... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Authors: Akio Mori, Taku Hatano, Tsuyoshi Inoshita, Kahori Shiba-Fukushima, Takahiro Koinuma, Hongrui Meng, Shin-ichiro Kubo, Spencer Spratt, Changxu Cui, Chikara Yamashita, Yoshimi Miki, Kei Yamamoto, Tetsuya Hirabayashi, Makoto Murakami, Yoshikazu Takahashi, Hid Tags: PNAS Plus Source Type: research

African trypanosomes expressing multiple VSGs are rapidly eliminated by the host immune system [Microbiology]
Trypanosoma brucei parasites successfully evade the host immune system by periodically switching the dense coat of variant surface glycoprotein (VSG) at the cell surface. Each parasite expresses VSGs in a monoallelic fashion that is tightly regulated. The consequences of exposing multiple VSGs during an infection, in terms of antibody response... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Authors: Francisco Aresta–Branco, Margarida Sanches–Vaz, Fabio Bento, Joao A. Rodrigues, Luisa M. Figueiredo Tags: PNAS Plus Source Type: research

Apparent thinning of human visual cortex during childhood is associated with myelination [Neuroscience]
Human cortex appears to thin during childhood development. However, the underlying microstructural mechanisms are unknown. Using functional magnetic resonance imaging (fMRI), quantitative MRI (qMRI), and diffusion MRI (dMRI) in children and adults, we tested what quantitative changes occur to gray and white matter in ventral temporal cortex (VTC) from childhood... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Authors: Vaidehi S. Natu, Jesse Gomez, Michael Barnett, Brianna Jeska, Evgeniya Kirilina, Carsten Jaeger, Zonglei Zhen, Siobhan Cox, Kevin S. Weiner, Nikolaus Weiskopf, Kalanit Grill-Spector Tags: PNAS Plus Source Type: research

Aldh1b1 expression defines progenitor cells in the adult pancreas and is required for Kras-induced pancreatic cancer [Medical Sciences]
The presence of progenitor or stem cells in the adult pancreas and their potential involvement in homeostasis and cancer development remain unresolved issues. Here, we show that mouse centroacinar cells can be identified and isolated by virtue of the mitochondrial enzyme Aldh1b1 that they uniquely express. These cells are necessary... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Authors: Ekaterina Mameishvili, Ioannis Serafimidis, Sara Iwaszkiewicz, Mathias Lesche, Susanne Reinhardt, Nora Bolicke, Maren Buttner, Dimitris Stellas, Adriana Papadimitropoulou, Matthias Szabolcs, Konstantinos Anastassiadis, Andreas Dahl, Fabian Theis, Argiris Tags: PNAS Plus Source Type: research

Glioblastoma ablates pericytes antitumor immune function through aberrant up-regulation of chaperone-mediated autophagy [Immunology and Inflammation]
The contractile perivascular cells, pericytes (PC), are hijacked by glioblastoma (GB) to facilitate tumor progression. PC’s protumorigenic function requires direct interaction with tumor cells and contributes to the establishment of immunotolerance to tumor growth. Cancer cells up-regulate their own chaperone-mediated autophagy (CMA), a process that delivers selective cytosolic proteins to... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Authors: Rut Valdor, David Garcia–Bernal, Dolores Riquelme, Carlos M. Martinez, Jose M. Moraleda, Ana Maria Cuervo, Fernando Macian, Salvador Martinez Tags: PNAS Plus Source Type: research

Crystal structure of cis-aconitate decarboxylase reveals the impact of naturally occurring human mutations on itaconate synthesis [Immunology and Inflammation]
cis-Aconitate decarboxylase (CAD, also known as ACOD1 or Irg1) converts cis-aconitate to itaconate and plays central roles in linking innate immunity with metabolism and in the biotechnological production of itaconic acid by Aspergillus terreus. We have elucidated the crystal structures of human and murine CADs and compared their enzymological properties... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - October 8, 2019 Category: Science Authors: Fangfang Chen, Peer Lukat, Azeem Ahmed Iqbal, Kyrill Saile, Volkhard Kaever, Joop van den Heuvel, Wulf Blankenfeldt, Konrad Bussow, Frank Pessler Tags: PNAS Plus Source Type: research