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

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• Bioenergetics of iron snow fueling life on Europa AI翻译
  作者：Sahai, Nita; LaRowe, Doug; Senko, John M.
  作者单位：University System of Ohio; University of Akron; University System of Ohio; University of Akron; University System of Ohio; University of Akron; University System of Ohio; University of Akron; University of Southern California
  摘要：The main sources of redox gradients supporting high - productivity life in the Europan and other icy ocean world oceans were proposed to be photolytically derived oxidants, such as reactive oxygen species (ROS) from the icy shell, and reductants (Fe(II), S( - II), CH 4 , H 2 ) from bottom waters reacting with a (ultra)mafic seafloor. Important roadblocks to maintaining life, however, are that the degree of ocean mixing to combine redox species is unknown, and ROS damage biomolecules. Here, we ...
• Modeling of brain efflux: Constraints of brain surfaces AI翻译
  作者：Bork, Peter A. R.; Hauglund, Natalie L.; Mori, Yuki; Mollgard, Kjeld; Hjorth, Poul G.; Nedergaard, Maiken
  作者单位：University of Copenhagen; University of Copenhagen; Technical University of Denmark
  摘要：Fluid efflux from the brain plays an important role in solute waste clearance. Current experimental approaches provide little spatial information, and data collection is limited due to short duration or low frequency of sampling. One approach shows tracer efflux to be independent of molecular size, indicating bulk flow, yet also decelerating like simple membrane diffusion. In an apparent contradiction to this report, other studies point to tracer efflux acceleration. We here develop a one-dime...
• OCA- B/Pou2af1 is sufficient to promote CD4+ T cell memory and pro-spectively identifies memory precursors (vol 121, e2309153121, 2024) AI翻译
  作者：Sun, Wenxiang; Hughes, Erik P.; Kim, Heejoo; Perovanovic, Jelena; Charley, Krystal R.; Perkins, Bryant; Du, Junhong; Ibarra, Andrea; Syage, Amber R.; Hale, J. Scot; Williams, Matthew A.; Tantin, Dean
• Conformational changes in the Niemann-Pick type C1 protein NCR1 drive sterol translocation AI翻译
  作者：Frain, Kelly M.; Dedic, Emil; Nel, Lynette; Bohush, Anastasiia; Olesen, Esben; Thaysen, Katja; Wustner, Daniel; Stokes, David L.; Pedersen, Bjorn Panyella
  作者单位：Aarhus University; Aarhus University; University of Southern Denmark; New York University
  摘要：The membrane protein Niemann-Pick type C1 (NPC1, named NCR1 in yeast) is central to sterol homeostasis in eukaryotes. Saccharomyces cerevisiae NCR1 is localized to the vacuolar membrane, where it is suggested to carry sterols across the protective glycocalyx and deposit them into the vacuolar membrane. However, documentation of a vacuolar glycocalyx in fungi is lacking, and the mechanism for sterol translocation has remained unclear. Here, we provide evidence supporting the presence of a glyco...
• Subgenome- aware analyses reveal the genomic consequences of ancient allopolyploid hybridizations throughout the cotton family AI翻译
  作者：Sun, Pengchuan; Lu, Zhiqiang; Wang, Zhenyue; Wang, Shang; Zhao, Kexin; Mei, Dong; Yang, Jiao; Yang, Yongzhi; Renner, Susanne S.; Liu, Jianquan
  作者单位：Sichuan University; Chinese Academy of Sciences; Xishuangbanna Tropical Botanical Garden, CAS; Lanzhou University; Washington University (WUSTL)
  摘要：Malvaceae comprise some 4,225 species in 243 genera and nine subfamilies and include economically important species, such as cacao, cotton, durian, and jute, with cotton an important model system for studying the domestication of polyploids. Here, we use chromosome - level genome assemblies from representatives of five or six subfamilies (depending on the placement of Ochroma) to differentiate coexisting subgenomes and their evolution during the family's deep history. The results reveal that t...
• Tropical paleobiology discovers biodiversity in a warmer past AI翻译
  作者：Yasuhara, Moriaki; Deutsch, Curtis A.; Zhang, Jingwen
  作者单位：University of Hong Kong; University of Hong Kong; City University of Hong Kong; Princeton University; Princeton University
• Removal of phosphoglycolate in hyperthermophilic archaea AI翻译
  作者：Michimori, Yuta; Izaki, Rikihisa; Su, Yu; Fukuyama, Yuto; Shimamura, Shigeru; Nishimura, Karin; Miwa, Yuya; Hamakita, Sotaro; Shimosaka, Takahiro; Makino, Yuki; Takeno, Ryo; Sato, Takaaki; Beppu, Haruki; Cann, Isaac; Kanai, Tamotsu; Nunoura, Takuro; Atomi, Haruyuki
  作者单位：Kyoto University; Kyoto University; Japan Agency for Marine-Earth Science & Technology (JAMSTEC); Japan Agency for Marine-Earth Science & Technology (JAMSTEC); Kyoto University; University of Illinois System; University of Illinois Urbana-Champaign
  摘要：Many organisms that utilize the Calvin-Benson-Bassham (CBB) cycle for autotrophic growth harbor metabolic pathways to remove and/or salvage 2- phosphoglycolate, the product of the oxygenase activity of ribulose-1,5- bisphosphate carboxylase/oxygenase (Rubisco). It has been presumed that the occurrence of 2- phosphoglycolate salvage is linked to the CBB cycle, and in particular, the C2 pathway to the CBB cycle and oxygenic photosynthesis. Here, we examined 2- phosphoglycolate salvage in the hyp...
• Reinforcement learning informs optimal treatment strategies to limit antibiotic resistance AI翻译
  作者：Weaver, Davis T.; King, Eshan S.; Maltas, Jeff; Scott, Jacob G.
  作者单位：University System of Ohio; Case Western Reserve University; Cleveland Clinic Foundation; University System of Ohio; Case Western Reserve University
  摘要：Antimicrobial resistance was estimated to be associated with 4.95 million deaths worldwide in 2019. It is possible to frame the antimicrobial resistance problem as a feedback -control problem. If we could optimize this feedback -control problem and translate our findings to the clinic, we could slow, prevent, or reverse the development of high-level drug resistance. Prior work on this topic has relied on systems where the exact dynamics and parameters were known a priori. In this study, we ext...
• Signal integration in chemoreceptor complexes AI翻译
  作者：Koler, Moriah; Parkinson, John S.; Vaknin, Ady
  作者单位：Hebrew University of Jerusalem; Utah System of Higher Education; University of Utah
  摘要：Motile bacteria use large receptor arrays to detect chemical and physical stimuli in their environment, process this complex information, and accordingly bias their swimming in a direction they deem favorable. The chemoreceptor molecules form tripod - like trimers of receptor dimers through direct contacts between their cytoplasmic tips. A pair of trimers, together with a dedicated kinase enzyme, form a core signaling complex. Hundreds of core complexes network to form extended arrays. While c...
• Elasticity and rheology of auxetic granular metamaterials AI翻译
  作者：Haver, Daan; Acuna, Daniel; Janbaz, Shahram; Lerner, Edan; During, Gustavo; Coulais, Corentin
  作者单位：University of Amsterdam; Universidad de Chile; Pontificia Universidad Catolica de Chile
  摘要：The flowing, jamming, and avalanche behavior of granular materials is satisfyingly universal and vexingly hard to tune: A granular flow is typically intermittent and will irremediably jam if too confined. Here, we show that granular metamaterials made from particles with a negative Poisson's ratio yield more easily and flow more smoothly than ordinary granular materials. We first create a collection of auxetic grains based on a re-entrant mechanism and show that each grain exhibits a negative ...