Ectopic callose deposition into woody biomass modulates the nano-architecture of macrofibrils

Plant biomass plays an increasingly important role in the circular bioeconomy, replacing non-renewable fossil resources. Genetic engineering of this lignocellulosic biomass could benefit biorefinery transformation chains by lowering economic and technological barriers to industrial processing. However, previous efforts have mostly targeted the major constituents of woody biomass: cellulose, hemicellulose and lignin. Here we report the engineering of wood structure through the introduction of callose, a polysaccharide novel to most secondary cell walls. Our multiscale analysis of genetically engineered poplar trees shows that callose deposition modulates cell wall porosity, water and lignin contents and increases the lignin-cellulose distance, ultimately resulting in substantially decreased biomass recalcitrance. We provide a model of the wood cell wall nano-architecture engineered to accommodate the hydrated callose inclusions. Ectopic polymer introduction into biomass manifests in new physico-chemical properties and offers new avenues when considering lignocellulose engineering.Bourdon et al. demonstrate the possibility to ectopically synthesize callose, a polymer restricted to primary cell walls, into Arabidopsis and aspen secondary cell walls to manipulate their ultrastructure and ultimately reduce their recalcitrance

Sleep as a protective factor of children’s executive functions: A study during COVID-19 confinement

Confinements due to the COVID-19 outbreak affected sleep and mental health of adults, adolescents and children. Already preschool children experienced acutely worsened sleep, yet the possible resulting effects on executive functions remain unexplored. Longitudinally, sleep quality predicts later behavioral-cognitive outcomes. Accordingly, we propose children’s sleep behavior as essential for healthy cognitive development. By using the COVID-19 confinement as an observational-experimental intervention, we tested whether worsened children’s sleep affects executive functions outcomes 6 months downstream. We hypothesized that acutely increased night awakenings and sleep latency relate to reduced later executive functions. With an online survey during the acute confinement phase we analyzed sleep behavior in 45 children (36–72 months). A first survey referred to the (retrospective) time before and (acute) situation during confinement, and a follow-up survey assessed executive functions 6 months later (6 months retrospectively). Indeed, acutely increased nighttime awakenings related to reduced inhibition at FOLLOW-UP. Associations were specific to the confinement-induced sleep-change and not the sleep behavior before confinement. These findings highlight that specifically acute changes of children’s nighttime sleep during sensitive periods are associated with behavioral outcome consequences. This aligns with observations in animals that inducing poor sleep during developmental periods affects later brain function

Sleep as a protective factor of children's executive functions: A study during COVID-19 confinement.

Confinements due to the COVID-19 outbreak affected sleep and mental health of adults, adolescents and children. Already preschool children experienced acutely worsened sleep, yet the possible resulting effects on executive functions remain unexplored. Longitudinally, sleep quality predicts later behavioral-cognitive outcomes. Accordingly, we propose children's sleep behavior as essential for healthy cognitive development. By using the COVID-19 confinement as an observational-experimental intervention, we tested whether worsened children's sleep affects executive functions outcomes 6 months downstream. We hypothesized that acutely increased night awakenings and sleep latency relate to reduced later executive functions. With an online survey during the acute confinement phase we analyzed sleep behavior in 45 children (36-72 months). A first survey referred to the (retrospective) time before and (acute) situation during confinement, and a follow-up survey assessed executive functions 6 months later (6 months retrospectively). Indeed, acutely increased nighttime awakenings related to reduced inhibition at FOLLOW-UP. Associations were specific to the confinement-induced sleep-change and not the sleep behavior before confinement. These findings highlight that specifically acute changes of children's nighttime sleep during sensitive periods are associated with behavioral outcome consequences. This aligns with observations in animals that inducing poor sleep during developmental periods affects later brain function

Lack of association between behavioral development and simplified topographical markers of the sleep EEG in infancy

The sleep EEG mirrors neuronal connectivity, especially during development when the brain undergoes substantial rewiring. As children grow, the slow-wave activity (SWA; 0.75–4.25 Hz) spatial distribution in their sleep EEG changes along a posterior-to-anterior gradient. Topographical SWA markers have been linked to critical neurobehavioral functions, such as motor skills, in school-aged children. However, the relationship between topographical markers in infancy and later behavioral outcomes is still unclear. This study aims to explore reliable indicators of neurodevelopment in infants by analyzing their sleep EEG patterns. Thirty-one 6-month-old infants (15 female) underwent high-density EEG recordings during nighttime sleep. We defined markers based on the topographical distribution of SWA and theta activity, including central/occipital and frontal/occipital ratios and an index derived from local EEG power variability. Linear models were applied to test whether markers relate to concurrent, later, or retrospective behavioral scores, assessed by the parent-reported Ages & Stages Questionnaire at ages 3, 6, 12, and 24 months. Results indicate that the topographical markers of the sleep EEG power in infants were not significantly linked to behavioral development at any age. Further research, such as longitudinal sleep EEG in newborns, is needed to better understand the relationship between these markers and behavioral development and assess their predictive value for individual differences

Evolution of the Flax Cell Wall Composition During Development and After Gravitropism by Synchrotron Fluorescence Imaging

Flax lodging is an issue of great interest for producers due to its economic impact. To better understand its effects at the cell wall and stem scale, new knowledge regarding the cell wall composition dynamics during cell wall development and after a 90° tilt bending stress is reported. Deep-Ultra Violet fluorescence emission (DUV) dynamics recorded at the Synchrotron SOLEIL-DISCO beamline by multichannel autofluorescence imaging is reported for five cellular wall types of flax stems after an artificially induced gravitropic reaction. Three flax growth development stages, namely, the vegetative stage (VS), the fast growth (FG) and the mature stage (MS), were selected in normal plants, referred to as the control plants, or in gravitropic-induced response plants, referred to as 90° tilted plants. <br /

Evolution of the flax cell wall composition during development and after gravitropism by synchrotron fluorescence imaging

International audienceFlax (Linum usitatissimum) lodging is an issue of great interest for industrial producers due to its economic impact; despite a strong varietal selection over around one century, this plant remains sensitive to lodging which represents a main technico-economic issue. To better understand lodging effects at the cell wall and stem scale, the cell wall composition dynamics during cell wall development and after a 90 degrees tilt bending stress is reported. Deep-UltraViolet (DUV) fluorescence emission dynamics recorded at the Synchrotron SOLEIL-DISCO beamline by multichannel autofluorescence imaging is addressed for five cellular wall types of flax stems after an artificially induced gravitropic reaction. The quantitative fluorescent profile intensities were computed after image analysis, and compared to the control flax stems, we reported a systematically higher average intensity fluorescence (probability >95%) for the 90 degrees tilted plants. Moreover, the average stem fluorescence intensities were significantly different among the 3 developmental stages, with the youngest stage (VS) exhibiting on average 30% and 20% less fluorescence than the medium (FG) and mature (M) stages, respectively. The flax stem response to tilt impacted the xylem cellular type, while the bast fibres were arguably less affected by the protein, and hydroxycinnamate contents. A complementary investigation was carried out on bast fibres by infrared microspectroscopy to explore the polysaccharide components not detected in DUV fluorescence, and significant modifications were monitored

Faire sans, faire avec moins

Usage réduit d’antibiotiques, ville sans voiture, agriculture sans pesticides, basse consommation énergétique, menus sans viande, etc. Cette liste, allongeable à souhait, amène à un constat sans appel. Les réponses aux défis qui traversent nos sociétés passent de plus en plus par la réduction, voire le retrait de certaines substances, technologies ou artefacts qui sont au cœur de nos modes de vie et de production. Faire sans, faire avec moins, sont ainsi devenus des horizons pour l’innovation. Quels sont les processus à l’œuvre ? En quoi les mécanismes et les propriétés de ces innovations sont-ils différents de ceux connus jusqu’alors ? En quoi ces innovations questionnent-elles les outils conceptuels des sciences sociales, notamment dans le domaine des science and technology studies ? Cet ouvrage collectif apporte des réponses à ces questions, à partir de réflexions théoriques et de travaux empiriques portant sur des secteurs aussi variés que l’agriculture, l’alimentation, la santé, la religion, l’énergie, les marchés ou le numérique. Il ouvre de nouvelles perspectives pour enrichir la compréhension des processus d’innovation et les transformations des sociétés contemporaines

Research data supporting “Ectopic callose deposition into woody biomass modulates the nano-architecture of macrofibrils”

The repository is divided in distinct folders which contain the raw data necessary to produce each figure of the “Ectopic callose deposition into woody biomass modulates the nano-architecture of macrofibrils” manuscript. As such, each folder is named after the figure it is referring to, and often contains several subfolders distinguishing the different data sets necessary to produce each figure. Each subfolder name ends up with the initials of the main co-author(s) originating the data they contain. See the 'Repository_readme' file for a detailed description of this dataseto The UK High-Field Solid-State NMR Facility used in this research was funded by EPSRC and BBSRC (EP/T015063/1) as well as the University of Warwick including via part funding through Birmingham Science City Advanced Materials Projects 1 and 2 supported by Advantage West Midlands (AWM) and the European Regional Development Fund (ERDF). We thank the Cambridge Advanced Imaging Center (CAIC) for providing access to their TEM resources and for technical assistance in imaging. The lignin analysis was supported by the Soluserre funding (Région Pays de la Loire, France). The authors acknowledge the funding received from the New Zealand Ministry of Business, Innovation, and Employment (MBIE) Strategic Science Investment Fund (Contract No. C0X41703, High-Value Biorefineries Portfolio) for supporting this work. FV acknowledges support from the Swedish Research Council (grants 621-2014-5295 and 2020-04720) and from the Knut and Alice Wallenberg Foundation (through the Wallenberg Wood Science Centre). Work in the YBA lab is supported by the Leverhulme Trust (Grant RPG-2016-136) which funded S.A. and C.P. and the UKRI Future Leader Fellowship program (MR/T04263X/1). Work in the JJL lab is supported by a grant from the National Science Centre Poland awarded to JJL as part of the SONATINA 3 programme (project number 2019/32/C/NZ3/00392) and a grant from National Science Centre Poland awarded as part of SONATA 17 programme (project number 2021/43/D/NZ9/01978). MB was supported by the ERC Proof of Concept APPLICAL (2020-2022) and the HiLife Proof of Concept APPLICAL (2020-2021) grants. L.K. received funding from the SNSF (P2LAP3_178062) and a Marie Curie IEF (No. 795250). Work in the YH lab was supported by the Finnish CoE in Molecular Biology of Primary Producers (Academy of Finland CoE programme 2014–2019) decision n°. 271832, the Gatsby Foundation (GAT3395/PR3), the University of Helsinki (award 799992091) and the ERC Advanced Investigator Grant SYMDEV (No. 323052)