Proceedings of the National Academy of Sciences of the United States of America

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• Revisiting the Eoarchean Akilia quartz- pyroxene rock with potassium isotopes: Implications for early- ocean sedimentation AI翻译
  作者：Long, Zheng - Yu; Moynier, Frederic; Dai, Wei; van Zuilen, Mark; Deng, Jun; Qiu, Kun - Feng- Feng
  作者单位：Universite Paris Cite; Centre National de la Recherche Scientifique (CNRS); China University of Geosciences; Universite de Bretagne Occidentale; Institut Universitaire Europeen de la Mer (IUEM); Naturalis Biodiversity Center
  摘要：The Eoarchean quartz-pyroxene rock from Akilia Island in Greenland has been proposed as one of Earth's oldest banded iron formations (BIF) and a potential host for the earliest biosignatures. However, the origin of its protolith, whether it metamorphosed from an igneous or sedimentary precursor, remains debated. Here, we revisit this longstanding Akilia controversy using potassium isotope analyses, comparing Akilia samples with BIFs and black shales spanning the Eoarchean to Mesoproterozoic. O...
• Hydrogen cyanide and hydrocarbons mix on Titan AI翻译
  作者：Izquierdo-Ruiz, Fernando; Cable, Morgan L.; Hodyss, Robert; Vu, Tuan H.; Sandstrom, Hilda; Lobato, Alvaro; Rahm, Martin
  作者单位：Chalmers University of Technology; Complutense University of Madrid; National Aeronautics & Space Administration (NASA); NASA Jet Propulsion Laboratory (JPL); California Institute of Technology
  摘要：This work reveals a striking exception to the well-established rule in chemistry that polar and nonpolar compounds do not spontaneously mix: insertion of methane, ethane, and other small hydrocarbons into the crystal lattice of hydrogen cyanide (HCN), a highly polar molecule. By mixing these components at cryogenic temperatures, we can observe distinct shifts in vibrational modes using Raman spectroscopy. Our computational predictions confirm that cocrystal structures of HCN and ethane, which ...
• 撤稿声明: Selective neutralization of IL-12 p40 monomer induces death in prostate cancer cells via IL-12-IFN-γ AI翻译
  作者：Kundu, Madhuchhanda; Roy, Avik; Pahan, Kalipada
• RACK1A positively regulates opening of the apical hook in Arabidopsis thaliana via suppression of its auxin response gradient AI翻译
  作者：Ma, Qian; Liu, Sijia; Doyle, Siamsa M.; Raggi, Sara; Parizkova, Barbora; Barange, Deepak Kumar; Ratnakaram, Hemamshu; Wilkinson, Edward G.; Garcia, Isidro Crespo; Bygdell, Joakim; Wingsle, Gunnar; Boer, Dirk Roeland; Strader, Lucia C.; Almqvist, Fredrik; Novak, Ondrej; Robert, Stephanie
  作者单位：Swedish University of Agricultural Sciences; Umea University; Palacky University Olomouc; Czech Academy of Sciences; Institute of Experimental Botany of the Czech Academy of Sciences; Umea University; Duke University; Umea University; Ghent University; Flanders Institute for Biotechnology (VIB); Shenyang Agricultural University; Swedish University of Agricultural Sciences; Umea University; Colorado State University System; Colorado State University Fort Collins
  摘要：Apical hook development is an ideal model for studying differential growth in plants and is controlled by complex phytohormonal crosstalk, with auxin being the major player. Here, we identified a bioactive small molecule that decelerates apical hook opening in Arabidopsis thaliana. Our genetic studies suggest that this molecule enhances or maintains the auxin maximum found in the inner hook side and requires certain auxin signaling components to direct target of this compound. We present data ...
• Amino acid transfer free energies reveal thermodynamic driving forces in biomolecular condensate formation AI翻译
  作者：Rekhi, Shiv; Mittal, Jeetain
  作者单位：Texas A&M University System; Texas A&M University College Station; Texas A&M University System; Texas A&M University College Station; Texas A&M University System; Texas A&M University College Station
  摘要：The self-assembly of intrinsically disordered proteins into biomolecular condensates depends on their primary sequence, leading to sequence-dependent phase separation. Computational methods to study this behavior often rely on residue-level interaction potentials that estimate the propensity of amino acids to partition between the dilute and dense phases. While distribution coefficients would provide the most direct measure of these potentials, their unavailability has led to the use of proxie...
• Trigger factor accelerates nascent chain compaction and folding AI翻译
  作者：Till, Katharina; Seinen, Anne-Bart; Wruck, Florian; Sunderlikova, Vanda; Galmozzi, Carla V.; Katranidis, Alexandros; Bukau, Bernd; Kramer, Guenter; Tans, Sander J.
  作者单位：AMOLF; Helmholtz Association; German Cancer Research Center (DKFZ); Consejo Superior de Investigaciones Cientificas (CSIC); University of Sevilla; CSIC-JA-USE - Instituto de Biomedicina de Sevilla (IBIS); Delft University of Technology
  摘要：Conformational control of nascent chains is poorly understood. Chaperones are known to stabilize, unfold, and disaggregate polypeptides away from the ribosome. In comparison, much less is known about the elementary conformational control mechanisms at the ribosome. Yet, proteins encounter major folding and aggregation challenges during translation. Here, using selective ribosome profiling and optical tweezers with correlated single- molecule fluorescence, with dihydrofolate reductase (DHFR) as...
• Electrokinetic propulsion for electronically integrated microscopic robots AI翻译
  作者：Hanson, Lucas C.; Reinhardt, William H.; Shrager, Scott; Sivakumar, Tarunyaa; Miskin, Marc Z.
  作者单位：University of Pennsylvania; University of Pennsylvania
  摘要：Semiconductor microelectronics are emerging as a powerful tool for building smart, autonomous sub-millimeter robots. Yet a number of existing microrobot platforms, despite significant advantages in speed, robustness, power consumption, or ease of fabrication, have no clear path toward electronics integration, limiting their potential for intelligence. Here, we show how to upgrade a class of self-propelled particles into electronically integrated microrobots, reaping the best of both platforms ...
• Mutualisms within light microhabitats are associated with sensory convergence in a mimetic butterfly community AI翻译
  作者：Wainwright, J. Benito; Loupasaki, Theodora; Ramirez, Francisco; Penry, Iestyn L.; England, Sam J.; Barker, Annalie; Meier, Joana I.; How, Martin J.; Roberts, Nicholas W.; Troscianko, Jolyon; Montgomery, Stephen H.
  作者单位：University of Bristol; Pontificia Universidad Catolica del Ecuador; Leibniz Institut fur Evolutions und Biodiversitatsforschung; University of Cambridge; Wellcome Trust Sanger Institute; University of Exeter; University of St Andrews
  摘要：Niche partitioning within variable habitats can expose species to distinct sensory information. Vision is the primary sensory modality used by many animals to interact with their habitat. However, the role of terrestrial light environment properties in shaping species assemblages and visual system evolution is not fully understood. By studying a diverse, sympatric community of mimetic butterflies, we demonstrate that forest architecture creates a mosaic of light microhabitats that drive adapti...
• Adaptive arousal regulation: Pharmacologically shifting the peak of the Yerkes-Dodson curve by catecholaminergic enhancement of arousal AI翻译
  作者：Beerendonk, Lola; Mejias, Jorge F.; Nuiten, Stijn A.; de Gee, Jan Willem; Zantvoord, Jasper B.; Fahrenfort, Johannes J.; van Gaal, Simon
  作者单位：University of Amsterdam; University of Amsterdam; University of Amsterdam; University of Basel; University of Amsterdam; Vrije Universiteit Amsterdam; Vrije Universiteit Amsterdam
  摘要：Performance typically peaks at moderate arousal levels, consistent with the Yerkes-Dodson law, as confirmed by recent human and mouse pupillometry studies. Arousal states are influenced by neuromodulators like catecholamines (noradrenaline and dopamine) and acetylcholine. To investigate their contributions to this law, we pharmacologically enhanced arousal while measuring human decision-making and spontaneous arousal fluctuations via pupil size. The catecholaminergic agent atomoxetine increase...
• Piezo2+ mechanosensory neurons orchestrate postnatal development through mechano-chemo-transduction of PDGFA signaling AI翻译
  作者：Meng, Lin; Feng, Jifan; Guo, Tingwei; Zhang, Mingyi; Cha, Sa; Chen, Peng; Ziaei, Heliya; Harouni, Aaron; Ho, Thach - Vu; Chai, Yang
  作者单位：University of Southern California; Jilin University
  摘要：Mechanical forces are ubiquitous and essential during vertebrate development, yet how these forces are translated into biochemical signals and regulate development during postnatal organogenesis remains poorly understood. While early embryogenesis relies on cell-autonomous mechanotransduction, the role of sensory innervation-abundant in postnatal stages-has been overlooked. Here, using the postnatal mouse molar development model, a system experiencing sustained mechanical forces and extensive ...