Profile of Patrick Cramer [Profiles]
Patrick Cramer’s interest in the scientific method may have been sparked by a childhood gift. While growing up, his parents gave him a kit to try little experiments at home that inspired him to become a scientist. Patrick Cramer. Image credit: Patrick Cramer. Cramer studied chemistry, first at the University... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 23, 2021 Category: Science Authors: Sandeep Ravindran Tags: PNAS Profiles Source Type: research

Structures and implications of TBP-nucleosome complexes [Biophysics and Computational Biology]
The TATA box-binding protein (TBP) is highly conserved throughout eukaryotes and plays a central role in the assembly of the transcription preinitiation complex (PIC) at gene promoters. TBP binds and bends DNA, and directs adjacent binding of the transcription factors TFIIA and TFIIB for PIC assembly. Here, we show that... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 23, 2021 Category: Science Authors: Haibo Wang, Le Xiong, Patrick Cramer Tags: Inaugural Articles, Biophysics and Computational Biology Biological Sciences Source Type: research

Experimental evidence for glass polymorphism in vitrified water droplets [Applied Physical Sciences]
The nature of amorphous ices has been debated for more than 35 years. In essence, the question is whether they are related to ice polymorphs or to liquids. The fact that amorphous ices are traditionally prepared from crystalline ice via pressure-induced amorphization has made a clear distinction tricky. In this... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 23, 2021 Category: Science Authors: Johannes Bachler, Johannes Giebelmann, Thomas Loerting Tags: Applied Physical Sciences Source Type: research

Molecular underpinnings and biogeochemical consequences of enhanced diatom growth in a warming Southern Ocean [Environmental Sciences]
The Southern Ocean (SO) harbors some of the most intense phytoplankton blooms on Earth. Changes in temperature and iron availability are expected to alter the intensity of SO phytoplankton blooms, but little is known about how these changes will influence community composition and downstream biogeochemical processes. We performed light-saturated experimental... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 23, 2021 Category: Science Authors: Loay J. Jabre, Andrew E. Allen, J. Scott P. McCain, John P. McCrow, Nancy Tenenbaum, Jenna L. Spackeen, Rachel E. Sipler, Beverley R. Green, Deborah A. Bronk, David A. Hutchins, Erin M. Bertrand Tags: Ecology, Environmental Sciences Biological Sciences Source Type: research

Optical conductivity and superconductivity in highly overdoped La2-xCaxCuO4 thin films [Physics]
We have used atomic layer-by-layer oxide molecular beam epitaxy to grow epitaxial thin films of La2−xCaxCuO4 with x up to 0.5, greatly exceeding the solubility limit of Ca in bulk systems (x∼0.12). A comparison of the optical conductivity measured by spectroscopic ellipsometry to prior predictions from dynamical mean-field theory demonstrates... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 23, 2021 Category: Science Authors: Gideok Kim, Ksenia S. Rabinovich, Alexander V. Boris, Alexander N. Yaresko, Y. Eren Suyolcu, Yu-Mi Wu, Peter A. van Aken, Georg Christiani, Gennady Logvenov, Bernhard Keimer Tags: Physics Physical Sciences Source Type: research

Predicting in vivo escape dynamics of HIV-1 from a broadly neutralizing antibody [Evolution]
Broadly neutralizing antibodies are promising candidates for treatment and prevention of HIV-1 infections. Such antibodies can temporarily suppress viral load in infected individuals; however, the virus often rebounds by escape mutants that have evolved resistance. In this paper, we map a fitness model of HIV-1 interacting with broadly neutralizing antibodies... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 23, 2021 Category: Science Authors: Matthiȷs Meiȷers, Kanika Vanshylla, Henning Gruell, Florian Klein, Michael Lassig Tags: Evolution Biological Sciences Source Type: research

Probabilistic discrimination of relative stimulus features in mice [Neuroscience]
During perceptual decision-making, the brain encodes the upcoming decision and the stimulus information in a mixed representation. Paradigms suitable for studying decision computations in isolation rely on stimulus comparisons, with choices depending on relative rather than absolute properties of the stimuli. The adoption of tasks requiring relative perceptual judgments in... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 23, 2021 Category: Science Authors: Dmitry R. Lyamzin, Ryo Aoki, Mohammad Abdolrahmani, Andrea Benucci Tags: Neuroscience Biological Sciences Source Type: research

Mechanism of the formation of proton transfer pathways in photosynthetic reaction centers [Biochemistry]
In photosynthetic reaction centers from purple bacteria (PbRCs) from Rhodobacter sphaeroides, the secondary quinone QB accepts two electrons and two protons via electron-coupled proton transfer (PT). Here, we identify PT pathways that proceed toward the QB binding site, using a quantum mechanical/molecular mechanical approach. As the first electron is transferred... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 23, 2021 Category: Science Authors: Yu Sugo, Keisuke Saito, Hiroshi Ishikita Tags: Biochemistry Biological Sciences Source Type: research

Three mutations repurpose a plant karrikin receptor to a strigolactone receptor [Plant Biology]
Uncovering the basis of small-molecule hormone receptors’ evolution is paramount to a complete understanding of how protein structure drives function. In plants, hormone receptors for strigolactones are well suited to evolutionary inquiries because closely related homologs have different ligand preferences. More importantly, because of facile plant transgenic systems, receptors can... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 23, 2021 Category: Science Authors: Amir Arellano–Saab, Michael Bunsick, Hasan Al Galib, Wenda Zhao, Stefan Schuetz, James Michael Bradley, Zhenhua Xu, Claresta Adityani, Asrinus Subha, Hayley McKay, Alexandre de Saint Germain, Francois–Didier Boyer, Christopher S. P. McErlean, Tags: Plant Biology Biological Sciences Source Type: research

EZH2 inhibits NK cell-mediated antitumor immunity by suppressing CXCL10 expression in an HDAC10-dependent manner [Medical Sciences]
Enhancer of zeste homolog 2 (EZH2) is a histone H3 lysine 27 methyltransferase that has been shown to function as an oncogene in some cancers. Previous reports have largely focused on the ability of EZH2 to regulate cell-intrinsic tumor regulatory pathways as its mechanism-of-oncogenic action. However, the role that EZH2-mediated... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 23, 2021 Category: Science Authors: Suresh Bugide, Romi Gupta, Michael R. Green, Narendra Wajapeyee Tags: Medical Sciences Biological Sciences Source Type: research

Notch-Jagged signaling complex defined by an interaction mosaic [Biochemistry]
The Notch signaling system links cellular fate to that of its neighbors, driving proliferation, apoptosis, and cell differentiation in metazoans, whereas dysfunction leads to debilitating developmental disorders and cancers. Other than a five-by-five domain complex, it is unclear how the 40 extracellular domains of the Notch1 receptor collectively engage the... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 23, 2021 Category: Science Authors: Matthieu R. Zeronian, Oleg Klykov, Julia Portell i de Montserrat, Maria J. Koniȷnenberg, Anamika Gaur, Richard A. Scheltema, Bert J. C. Janssen Tags: Biochemistry Biological Sciences Source Type: research

Historical language records reveal a surge of cognitive distortions in recent decades [Computer Sciences]
Individuals with depression are prone to maladaptive patterns of thinking, known as cognitive distortions, whereby they think about themselves, the world, and the future in overly negative and inaccurate ways. These distortions are associated with marked changes in an individual’s mood, behavior, and language. We hypothesize that societies can undergo... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 23, 2021 Category: Science Authors: Johan Bollen, Marijn ten Thij, Fritz Breithaupt, Alexander T. J. Barron, Lauren A. Rutter, Lorenzo Lorenzo-Luaces, Marten Scheffer Tags: Computer Sciences, Psychological and Cognitive Sciences Social Sciences Source Type: research

Fossilized cell structures identify an ancient origin for the teleost whole-genome duplication [Evolution]
Teleost fishes comprise one-half of all vertebrate species and possess a duplicated genome. This whole-genome duplication (WGD) occurred on the teleost stem lineage in an ancient common ancestor of all living teleosts and is hypothesized as a trigger of their exceptional evolutionary radiation. Genomic and phylogenetic data indicate that WGD... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 23, 2021 Category: Science Authors: Donald Davesne, Matt Friedman, Armin D. Schmitt, Vincent Fernandez, Giorgio Carnevale, Per E. Ahlberg, Sophie Sanchez, Roger B. J. Benson Tags: Evolution Biological Sciences Source Type: research

Metastability and discrete spectrum of long-range systems [Physics]
Long-lived quasi-stationary states (QSSs) are a signature characteristic of long-range interacting systems both in the classical and in the quantum realms. Often, they emerge after a sudden quench of the Hamiltonian internal parameters and present a macroscopic lifetime, which increases with the system size. Despite their ubiquity, the fundamental mechanism... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 23, 2021 Category: Science Authors: Nicolo Defenu Tags: Physics Physical Sciences Source Type: research

Repeating caldera collapse events constrain fault friction at the kilometer scale [Earth, Atmospheric, and Planetary Sciences]
Fault friction is central to understanding earthquakes, yet laboratory rock mechanics experiments are restricted to, at most, meter scale. Questions thus remain as to the applicability of measured frictional properties to faulting in situ. In particular, the slip-weakening distance dc strongly influences precursory slip during earthquake nucleation, but scales with... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 23, 2021 Category: Science Authors: Paul Segall, Kyle Anderson Tags: Earth, Atmospheric, and Planetary Sciences Physical Sciences Source Type: research

Observation of others’ threat reactions recovers memories previously shaped by firsthand experiences [Psychological and Cognitive Sciences]
Information about dangers can spread effectively by observation of others’ threat responses. Yet, it is unclear if such observational threat information interacts with associative memories that are shaped by the individual’s direct, firsthand experiences. Here, we show in humans and rats that the mere observation of a conspecific’s threat reactions... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 23, 2021 Category: Science Authors: Jan Haaker, Lorenzo Diaz-Mataix, Gemma Guillazo-Blanch, Sara A. Stark, Lea Kern, Joseph E. LeDoux, Andreas Olsson Tags: Psychological and Cognitive Sciences Social Sciences Source Type: research

Thermodynamic profile of mutual subunit control in a heteromeric receptor [Biophysics and Computational Biology]
Cyclic nucleotide-gated (CNG) ion channels of olfactory neurons are tetrameric membrane receptors that are composed of two A2 subunits, one A4 subunit, and one B1b subunit. Each subunit carries a cyclic nucleotide-binding domain in the carboxyl terminus, and the channels are activated by the binding of cyclic nucleotides. The mechanism... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 23, 2021 Category: Science Authors: Jana Schirmeyer, Sabine Hummert, Thomas Eick, Eckhard Schulz, Tina Schwabe, Gunter Ehrlich, Taulant Kukaȷ, Melanie Wiegand, Christian Sattler, Ralf Schmauder, Thomas Zimmer, Nisa Kosmalla, Jan Munch, Michele Bonus, Holger Gohlke, Klaus Benndorf Tags: Biophysics and Computational Biology, Physiology Biological Sciences Source Type: research

MYO1F regulates antifungal immunity by regulating acetylation of microtubules [Immunology and Inflammation]
Opportunistic fungal infections have become one of the leading causes of death among immunocompromised patients, resulting in an estimated 1.5 million deaths each year worldwide. The molecular mechanisms that promote host defense against fungal infections remain elusive. Here, we find that Myosin IF (MYO1F), an unconventional myosin, promotes the expression... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 23, 2021 Category: Science Authors: Wanwei Sun, Xiaojian Ma, Heping Wang, Yanyun Du, Jianwen Chen, Huijun Hu, Ru Gao, Ruirui He, Qianwen Peng, Zhihui Cui, Huazhi Zhang, Junhan Wang, Xinming Jia, Bradley N. Martin, Cun-Jin Zhang, Xiaoxia Li, Chenhui Wang Tags: Immunology and Inflammation Biological Sciences Source Type: research

Multiple flat bands and topological Hofstadter butterfly in twisted bilayer graphene close to the second magic angle [Physics]
Moiré superlattices in two-dimensional van der Waals heterostructures provide an efficient way to engineer electron band properties. The recent discovery of exotic quantum phases and their interplay in twisted bilayer graphene (tBLG) has made this moiré system one of the most renowned condensed matter platforms. So far studies of tBLG... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 23, 2021 Category: Science Authors: Xiaobo Lu, Biao Lian, Gaurav Chaudhary, Benjamin A. Piot, Giulio Romagnoli, Kenji Watanabe, Takashi Taniguchi, Martino Poggio, Allan H. MacDonald, B. Andrei Bernevig, Dmitri K. Efetov Tags: Physics Physical Sciences Source Type: research

Structural basis for ligand binding modes of CTP synthase [Biochemistry]
Cytidine triphosphate synthase (CTPS), which comprises an ammonia ligase domain and a glutamine amidotransferase domain, catalyzes the final step of de novo CTP biosynthesis. The activity of CTPS is regulated by the binding of four nucleotides and glutamine. While glutamine serves as an ammonia donor for the ATP-dependent conversion of... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 23, 2021 Category: Science Authors: Xian Zhou, Chen-Jun Guo, Chia-Chun Chang, Jiale Zhong, Huan-Huan Hu, Guang-Ming Lu, Ji-Long Liu Tags: Biochemistry Biological Sciences Source Type: research

Dopaminergic brainstem disconnection is common to pharmacological and pathological consciousness perturbation [Neuroscience]
Clinical research into consciousness has long focused on cortical macroscopic networks and their disruption in pathological or pharmacological consciousness perturbation. Despite demonstrating diagnostic utility in disorders of consciousness (DoC) and monitoring anesthetic depth, these cortico-centric approaches have been unable to characterize which neurochemical systems may underpin consciousness alterations. Instead, preclinical... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 23, 2021 Category: Science Authors: Lennart R. B. Spindler, Andrea I. Luppi, Ram M. Adapa, Michael M. Craig, Peter Coppola, Alexander R. D. Peattie, Anne E. Manktelow, Paola Finoia, Barbara J. Sahakian, Guy B. Williams, Judith Allanson, John D. Pickard, David K. Menon, Emmanuel A. Stamataki Tags: Neuroscience Biological Sciences Source Type: research

Galectin-3 promotes noncanonical inflammasome activation through intracellular binding to lipopolysaccharide glycans [Immunology and Inflammation]
Cytosolic lipopolysaccharides (LPSs) bind directly to caspase-4/5/11 through their lipid A moiety, inducing inflammatory caspase oligomerization and activation, which is identified as the noncanonical inflammasome pathway. Galectins, β-galactoside–binding proteins, bind to various gram-negative bacterial LPS, which display β-galactoside–containing polysaccharide chains. Galectins are mainly present intracellularly, but their interactions with cytosolic... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 23, 2021 Category: Science Authors: Tzu-Han Lo, Hung-Lin Chen, Cheng-I Yao, I-Chun Weng, Chi-Shan Li, Chi-Chun Huang, Nien-Jung Chen, Chun-Hung Lin, Fu-Tong Liu Tags: Immunology and Inflammation Biological Sciences Source Type: research

Wireless, battery-free, subdermally implantable platforms for transcranial and long-range optogenetics in freely moving animals [Neuroscience]
Wireless, battery-free, and fully subdermally implantable optogenetic tools are poised to transform neurobiological research in freely moving animals. Current-generation wireless devices are sufficiently small, thin, and light for subdermal implantation, offering some advantages over tethered methods for naturalistic behavior. Yet current devices using wireless power delivery require invasive stimulus delivery,... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 23, 2021 Category: Science Authors: Jokubas Ausra, Mingzheng Wu, Xin Zhang, Abraham Vazquez–Guardado, Patrick Skelton, Roberto Peralta, Raudel Avila, Thomas Murickan, Chad R. Haney, Yonggang Huang, John A. Rogers, Yevgenia Kozorovitskiy, Philipp Gutruf Tags: Engineering, Neuroscience Physical Sciences Source Type: research

Benthic jellyfish dominate water mixing in mangrove ecosystems [Ecology]
Water mixing is a critical mechanism in marine habitats that governs many important processes, including nutrient transport. Physical mechanisms, such as winds or tides, are primarily responsible for mixing effects in shallow coastal systems, but the sheltered habitats adjacent to mangroves experience very low turbulence and vertical mixing. The significance... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 23, 2021 Category: Science Authors: David M. Durieux, Kevin T. Du Clos, David B. Lewis, Brad J. Gemmell Tags: Ecology Biological Sciences Source Type: research

Exploring the origins of the indentation size effect at submicron scales [Applied Physical Sciences]
The origin of the indentation size effect has been extensively researched over the last three decades, following the establishment of nanoindentation as a broadly used small-scale mechanical testing technique that enables hardness measurements at submicrometer scales. However, a mechanistic understanding of the indentation size effect based on direct experimental observations... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 23, 2021 Category: Science Authors: Xiaolong Ma, Wesley Higgins, Zhiyuan Liang, Dexin Zhao, George M. Pharr, Kelvin Y. Xie Tags: Applied Physical Sciences Source Type: research

Treg-expressed CTLA-4 depletes CD80/CD86 by trogocytosis, releasing free PD-L1 on antigen-presenting cells [Immunology and Inflammation]
Foxp3-expressing CD4+CD25+ regulatory T cells (Tregs) constitutively and highly express the immune checkpoint receptor cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4), whose Treg-specific deficiency causes severe systemic autoimmunity. As a key mechanism of Treg-mediated suppression, Treg-expressed CTLA-4 down-regulates the expression of CD80/CD86 costimulatory molecules on antigen-presenting cells (APCs). Here, we show that Treg-expressed... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 23, 2021 Category: Science Authors: Murat Tekguc, James Badger Wing, Motonao Osaki, Jia Long, Shimon Sakaguchi Tags: Immunology and Inflammation Biological Sciences Source Type: research

Arrest of WNT/{beta}-catenin signaling enables the transition from pluripotent to differentiated germ cells in mouse ovaries [Developmental Biology]
Germ cells form the basis for sexual reproduction by producing gametes. In ovaries, primordial germ cells exit the cell cycle and the pluripotency-associated state, differentiate into oogonia, and initiate meiosis. Despite the importance of germ cell differentiation for sexual reproduction, signaling pathways regulating their fate remain largely unknown. Here, we... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 23, 2021 Category: Science Authors: Morgane Le Rolle, Filippo Massa, Pam Siggers, Laurent Turchi, Agnes Loubat, Bon–Kyoung Koo, Hans Clevers, Andy Greenfield, Andreas Schedl, Marie–Christine Chaboissier, Anne–Amandine Chassot Tags: Developmental Biology Biological Sciences Source Type: research

The salience of choice fuels independence: Implications for self-perception, cognition, and behavior [Psychological and Cognitive Sciences]
More than ever before, people across the world are exposed to ideas of choice and have opportunities to make choices. What are the consequences of this rapidly expanding exposure to the ideas and practice of choice? The current research investigated an unexamined and potentially powerful consequence of this salience of... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 23, 2021 Category: Science Authors: Kevin Nanakdewa, Shilpa Madan, Krishna Savani, Hazel Rose Markus Tags: Psychological and Cognitive Sciences Social Sciences Source Type: research

Tsc1 regulates tight junction independent of mTORC1 [Cell Biology]
Tuberous sclerosis complex 1 (Tsc1) is a tumor suppressor that functions together with Tsc2 to negatively regulate the mechanistic target of rapamycin complex 1 (mTORC1) activity. Here, we show that Tsc1 has a critical role in the tight junction (TJ) formation of epithelium, independent of its role in Tsc2 and... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 23, 2021 Category: Science Authors: Mingqiang Lai, Wenchong Zou, Zelong Han, Ling Zhou, Zeyou Qiu, Juan Chen, Sheng Zhang, Pinglin Lai, Kai Li, Yue Zhang, Li Liang, Yu Jiang, Zhipeng Zou, Xiaochun Bai Tags: Cell Biology Biological Sciences Source Type: research

Active dendrites enable strong but sparse inputs to determine orientation selectivity [Neuroscience]
The dendrites of neocortical pyramidal neurons are excitable. However, it is unknown how synaptic inputs engage nonlinear dendritic mechanisms during sensory processing in vivo, and how they in turn influence action potential output. Here, we provide a quantitative account of the relationship between synaptic inputs, nonlinear dendritic events, and action... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 23, 2021 Category: Science Authors: Lea Goetz, Arnd Roth, Michael Hausser Tags: Neuroscience Biological Sciences Source Type: research

Accelerated expansion of pathogenic mitochondrial DNA heteroplasmies in Huntington’s disease [Genetics]
Mitochondrial dysfunction is found in the brain and peripheral tissues of patients diagnosed with Huntington’s disease (HD), an irreversible neurodegenerative disease of which aging is a major risk factor. Mitochondrial function is encoded by not only nuclear DNA but also DNA within mitochondria (mtDNA). Expansion of mtDNA heteroplasmies (coexistence of... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 23, 2021 Category: Science Authors: Yiqin Wang, Xiaoxian Guo, Kaixiong Ye, Michael Orth, Zhenglong Gu Tags: Genetics Biological Sciences Source Type: research

Middle Pleistocene fire use: The first signal of widespread cultural diffusion in human evolution [Anthropology]
Control of fire is one of the most important technological innovations within the evolution of humankind. The archaeological signal of fire use becomes very visible from around 400,000 y ago onward. Interestingly, this occurs at a geologically similar time over major parts of the Old World, in Africa, as well... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 23, 2021 Category: Science Authors: Katharine MacDonald, Fulco Scherjon, Eva van Veen, Krist Vaesen, Wil Roebroeks Tags: Anthropology, Perspectives Source Type: research

A physiologic rise in cytoplasmic calcium ion signal increases pannexin1 channel activity via a C-terminus phosphorylation by CaMKII [Physiology]
Pannexin1 (Panx1) channels are ubiquitously expressed in vertebrate cells and are widely accepted as adenosine triphosphate (ATP)-releasing membrane channels. Activation of Panx1 has been associated with phosphorylation in a specific tyrosine residue or cleavage of its C-terminal domains. In the present work, we identified a residue (S394) as a putative... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 23, 2021 Category: Science Authors: Ximena Lopez, Nicolas Palacios–Prado, Juan Guiza, Rosalba Escamilla, Paola Fernandez, Jose L. Vega, Maximiliano Roȷas, Valeria Marquez–Miranda, Eduardo Chamorro, Ana M. Cardenas, Maria Constanza Maldifassi, Agustin D. Martinez, Yorley D Tags: Inaugural Articles, Physiology Biological Sciences Source Type: research

RNA polymerase spoiled for choice as transcription begins [Biochemistry]
Papers concerning transcription, and its regulation at promoters, abound in the scientific literature, but reports about initiation, defined as the moment that the first 3′−5′phosphodiester bond of a new transcript is forged, are scarce. In PNAS, Skalenko et al. (1), working with the bacterial multisubunit DNA-dependent RNA polymerase (RNAP), combine... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 22, 2021 Category: Science Authors: Stephen J. W. Busby Tags: Biochemistry, Commentaries Commentary Source Type: research

Trading and weighing metals in Bronze Age Western Eurasia [Anthropology]
The Bronze Age weight systems article (1) uniquely unveils Western Eurasia as a vast marketplace made by private merchants in 3000 to 1000 BC. Hypotheses spring from macroeconomic concepts such as market equilibrium, prices, and self-regulation. The demonstrated long-term spread of weighing technology from a common Mesopotamian source, beginning ca.... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 22, 2021 Category: Science Authors: Helle Vandkilde Tags: Anthropology, Commentaries Commentary Source Type: research

Ancient DNA from the koala lemur puts Madagascar on the paleogenomic map [Anthropology]
In the Southern Hemisphere, there are two exceptionally large noncontinental landmasses with very long histories of geographical isolation—New Zealand and Madagascar. Both landmasses have unique and distinctive fauna and flora that nonetheless present a number of intriguing parallels, including the long-term preservation of distant sister lineages to otherwise globally widespread... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 22, 2021 Category: Science Authors: Kieren J. Mitchell Tags: Anthropology, Commentaries Commentary Source Type: research

NMR spectroscopy charges into protein surface electrostatics [Biophysics and Computational Biology]
Life needs interaction. The current pandemic has made visible how much interaction, or lack thereof, means for the life of each and every one of us. The validity of this statement also extends to the tiny and invisible: Over the years, scientists have taken key steps to understand the interactions... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 22, 2021 Category: Science Authors: Frans A. A. Mulder Tags: Biophysics and Computational Biology, Commentaries Commentary Source Type: research

A new protein protects a symbiotic relationship [Evolution]
A month ago Twitter was buzzing with news of Brood X cicadas. People were eating them, posting pictures of them, requesting gifts of them for their child’s pinned insect collection, and I was wondering how far north I would have to go to see them. Brood X cicadas are amazing... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 22, 2021 Category: Science Authors: Alex C. C. Wilson Tags: Evolution, Commentaries Commentary Source Type: research

The archaeology of climate change: The case for cultural diversity [Sustainability Science]
Anthropogenic climate change is currently driving environmental transformation on a scale and at a pace that exceeds historical records. This represents an undeniably serious challenge to existing social, political, and economic systems. Humans have successfully faced similar challenges in the past, however. The archaeological record and Earth archives offer rare... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 22, 2021 Category: Science Authors: Ariane Burke, Matthew C. Peros, Colin D. Wren, Francesco S. R. Pausata, Julien Riel–Salvatore, Olivier Moine, Anne de Vernal, Masa Kageyama, Solene Boisard Tags: Environmental Sciences, Perspectives, Sustainability Science Source Type: research

Reply to Rugenstein et al.: Marine Sr and Os records do not preclude Neogene cooling through emergence of the Southeast Asian islands [Physical Sciences]
In Park et al. (1) we used a coupled climate and silicate weathering model (GEOCLIM) to make the case that emergence of the Southeast Asian islands (SEAIs) played a significant role in cooling Earth’s climate over the past 15 My. The findings were that mountains built through arc–continent collision in... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 22, 2021 Category: Science Authors: Yuem Park, Pierre Maffre, Yves Godderis, Francis A. Macdonald, Eliel S. C. Anttila, Nicholas L. Swanson–Hysell Tags: Earth, Atmospheric, and Planetary Sciences, Letters, Letters and Replies Source Type: research

Characterization of DNA-protein complexes by nanoparticle tracking analysis and their association with systemic lupus erythematosus [Applied Biological Sciences]
Nanotechnology enables investigations of single biomacromolecules, but technical challenges have limited the application in liquid biopsies, for example, blood plasma. Nonetheless, tools to characterize single molecular species in such samples represent a significant unmet need with the increasing appreciation of the physiological importance of protein structural changes at nanometer scale.... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 22, 2021 Category: Science Authors: Kristian Juul–Madsen, Anne Troldborg, Thomas R. Wittenborn, Mads G. Axelsen, Huaying Zhao, Lasse H. Klausen, Stefanie Luecke, Soren R. Paludan, Kristian Stengaard–Pedersen, Mingdong Dong, Holger J. Moller, Steffen Thiel, Henrik Jensen, Peter S Tags: Applied Biological Sciences Source Type: research

Flowering in bursting bubbles with viscoelastic interfaces [Engineering]
The lifetime of bubbles, from formation to rupture, attracts attention because bubbles are often present in natural and industrial processes, and their geometry, drainage, coarsening, and rupture strongly affect those operations. Bubble rupture happens rapidly, and it may generate a cascade of small droplets or bubbles. Once a hole is... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 22, 2021 Category: Science Authors: Daniele Tammaro, Vinny Chandran Suja, Aadithya Kannan, Luigi Davide Gala, Ernesto Di Maio, Gerald G. Fuller, Pier Luca Maffettone Tags: Engineering Physical Sciences Source Type: research

Inside-out regulation of E-cadherin conformation and adhesion [Biophysics and Computational Biology]
Cadherin cell–cell adhesion proteins play key roles in tissue morphogenesis and wound healing. Cadherin ectodomains bind in two conformations, X-dimers and strand-swap dimers, with different adhesive properties. However, the mechanisms by which cells regulate ectodomain conformation are unknown. Cadherin intracellular regions associate with several actin-binding proteins including vinculin, which are... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 22, 2021 Category: Science Authors: Ramesh Koirala, Andrew Vae Priest, Chi-Fu Yen, Joleen S. Cheah, Willem-Jan Pannekoek, Martijn Gloerich, Soichiro Yamada, Sanjeevi Sivasankar Tags: Biophysics and Computational Biology Biological Sciences Source Type: research

Chromosome 10q26-driven age-related macular degeneration is associated with reduced levels of HTRA1 in human retinal pigment epithelium [Genetics]
Genome-wide association studies have identified the chromosome 10q26 (Chr10) locus, which contains the age-related maculopathy susceptibility 2 (ARMS2) and high temperature requirement A serine peptidase 1 (HTRA1) genes, as the strongest genetic risk factor for age-related macular degeneration (AMD) [L.G. Fritsche et al., Annu. Rev. Genomics Hum. Genet. 15, 151–171,... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 22, 2021 Category: Science Authors: Brandi L. Williams, Nathan A. Seager, Jamie D. Gardiner, Chris M. Pappas, Monica C. Cronin, Cristina Amat di San Filippo, Robert A. Anstadt, Jin Liu, Marc A. Toso, Lisa Nichols, Timothy J. Parnell, Jacqueline R. Eve, Paul L. Bartel, Moussa A. Zouache, Bur Tags: Genetics Biological Sciences Source Type: research

Mechanotaxis directs Pseudomonas aeruginosa twitching motility [Biophysics and Computational Biology]
The opportunistic pathogen Pseudomonas aeruginosa explores surfaces using twitching motility powered by retractile extracellular filaments called type IV pili (T4P). Single cells twitch by sequential T4P extension, attachment, and retraction. How single cells coordinate T4P to efficiently navigate surfaces remains unclear. We demonstrate that P. aeruginosa actively directs twitching in... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 22, 2021 Category: Science Authors: Marco J. Kuhn, Lorenzo Tala, Yuki F. Inclan, Ramiro Patino, Xavier Pierrat, Iscia Vos, Zainebe Al–Mayyah, Henriette Macmillan, Jose Negrete Jr, Joanne N. Engel, Alexandre Persat Tags: Biophysics and Computational Biology, Microbiology Biological Sciences Source Type: research

An otopetrin family proton channel promotes cellular acid efflux critical for biomineralization in a marine calcifier [Physiology]
Otopetrins comprise a family of proton-selective channels that are critically important for the mineralization of otoliths and statoconia in vertebrates but whose underlying cellular mechanisms remain largely unknown. Here, we demonstrate that otopetrins are critically involved in the calcification process by providing an exit route for protons liberated by the... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 22, 2021 Category: Science Authors: William W. Chang, Ann–Sophie Matt, Marcus Schewe, Marianne Musinszki, Sandra Grussel, Jonas Brandenburg, David Garfield, Markus Bleich, Thomas Baukrowitz, Marian Y. Hu Tags: Physiology Biological Sciences Source Type: research

The magnitude of germinal center reactions is restricted by a fixed number of preexisting niches [Immunology and Inflammation]
Antibody affinity maturation occurs in the germinal center (GC), a highly dynamic structure that arises upon antigen stimulation and recedes after infection is resolved. While the magnitude of the GC reaction is highly fluctuating and depends on antigens or pathological conditions, it is unclear whether GCs are assembled ad hoc... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 22, 2021 Category: Science Authors: Patricia Avancena, Tengfei Song, Yonghong Yao, Hannah Fehlner-Peach, Betty Diamond, Hua Gu, Klaus Rajewsky, Yong-Rui Zou Tags: Immunology and Inflammation Biological Sciences Source Type: research

Isotope mass-balance constraints preclude that mafic weathering drove Neogene cooling [Physical Sciences]
Park et al. (1) use a global biogeochemical model (GEOCLIM) to suggest that weathering associated with emergence of mafic islands in Southeast Asia resulted in a ∼350-ppm decrease in atmospheric CO2 during the last 15 Ma. However, only matching pCO2 yields nonunique solutions that cannot be distinguished from previous hypotheses,... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 22, 2021 Category: Science Authors: Jeremy K. Caves Rugenstein, Daniel E. Ibarra, Shuang Zhang, Noah J. Planavsky, Friedhelm von Blanckenburg Tags: Earth, Atmospheric, and Planetary Sciences, Letters, Letters and Replies Source Type: research

KRAS4A induces metastatic lung adenocarcinomas in vivo in the absence of the KRAS4B isoform [Genetics]
In mammals, the KRAS locus encodes two protein isoforms, KRAS4A and KRAS4B, which differ only in their C terminus via alternative splicing of distinct fourth exons. Previous studies have shown that whereas KRAS expression is essential for mouse development, the KRAS4A isoform is expendable. Here, we have generated a mouse... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 22, 2021 Category: Science Authors: Marina Salmon, Guillem Paniagua, Carmen G. Lechuga, Fernando Fernandez–Garcia, Eduardo Zarzuela, Ruth Alvarez–Diaz, Monica Musteanu, Carmen Guerra, Eduardo Caleiras, Javier Munoz, Sagrario Ortega, Matthias Drosten, Mariano Barbacid Tags: Genetics Biological Sciences Source Type: research

Cell membrane-camouflaged liposomes for tumor cell-selective glycans engineering and imaging in vivo [Biophysics and Computational Biology]
The dynamic change of cell-surface glycans is involved in diverse biological and pathological events such as oncogenesis and metastasis. Despite tremendous efforts, it remains a great challenge to selectively distinguish and label glycans of different cancer cells or cancer subtypes. Inspired by biomimetic cell membrane–coating technology, herein, we construct pH-responsive... (Source: Proceedings of the National Academy of Sciences)
Source: Proceedings of the National Academy of Sciences - July 22, 2021 Category: Science Authors: Zhengwei Liu, Faming Wang, Xinping Liu, Yanjuan Sang, Lu Zhang, Jinsong Ren, Xiaogang Qu Tags: Biophysics and Computational Biology, Chemistry Physical Sciences Source Type: research