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Two anchoring proteins control daughter apical complex assembly in Toxoplasma gondii
No full textDuring Toxoplasma gondii division, the apical complex—comprising the conoid, apical polar ring (APR), and preconoidal rings—assembles with precise spatiotemporal coordination to form functional daughter buds. Despite their essential roles in invasion, motility, and division, the scaffolding proteins orchestrating this ordered assembly have remained largely unidentified. Here, we identify and characterize RCC1-2 and APR8 as essential factors directing distinct, sequential phases of daughter cell apical complex construction. Both proteins are recruited with precise spatial and temporal dynamics to the daughter buds, where they function as scaffolds rather than static structural components. APR8 transiently occupies the basal region of the APR specifically in early daughter cells. It is dispensable for conoid and PCR initiation, yet its loss causes APR collapse, abolishes SPMT anchoring, and eventually arrests conoid maturation. In contrast, RCC1-2 localizes beneath the APR basal layer and persists throughout daughter cell development, where it contributes to stabilizing the attachment of SPMTs to the APR. Notably, in situ cryo-electron tomography further reveals that the interspersed pillars bridging SPMTs ends to the APR fail to form properly in RCC1-2-depleted parasites. These findings map a hierarchical RCC1-2/APR8-dependent scaffolding process that advances our understanding of parasite replication
Marketing: driving changes in livestock farming systems
No full textInternational audienceIn addition to the hazards and constraints associated with changes in the physical environment, the evolution of agricultural markets, especially the organization of downstream operators, implies transformations in livestock farming systems. Our goal is to demonstrate how product marketing helps shape the transformations of livestock farming systems, enhancing flexibility and resilience, toward agroecological transition. We propose the notion of a mode of marketing as a set of product–buyer pairs characterized by their volume and their annual temporal distribution. 50 livestock farmers were interviewed to describe the diversity of modes of marketing existing in the suckler sheep herd sector in a pastoral region in southern France. We monitored eight of them for three years and analyzed changes in the modes of marketing, breeding practices. We also analyzed the evolutions of associated value chains. For eight other farms, we conducted a retrospective analysis covering several decades. Our results highlighted three farmers’ strategies based on the choice of a mode of marketing at the campaign scale. We showed that this choice is a way to manage the different market risks. Furthermore, it impacted breeding practices. Over the medium term, we observed that seven of the eight farmers monitored changed their modes of marketing under market signals. These changes implied transformations in the management of the livestock farming systems. During their careers, the eight old farmers have changed their mode of marketing several times. We concluded that the choice of modes of marketing, and their changes, are a means of managing different market risks. Depending on the timing and the extent of their changes, it could be a source of operational or strategic flexibility. Modes of marketing must be considered to understand and support transformations in livestock farming systems toward the agroecological transition, as a way of resilience
Root phenolics as potential drivers of preformed defenses and reduced disease susceptibility in a paradigm bread wheat mixture
No full textInternational audiencePlant-plant interactions modulate foliar disease susceptibility in intraspecific mixtures. However, the molecular events including signals and responses underlying the reduction in disease susceptibility remain largely unexplored. Here, we developed an experimental system that can abolish root-mediated interactions between plants in a model of bread wheat varietal mixture. We then performed transcriptomic and metabolomic analyses to uncover the molecular responses linked to decreased susceptibility to Septoria tritici blotch in plant-plant interactions. Our analysis revealed that disrupting root chemical interactions impaired the reduction in susceptibility to Septoria and identified phenolic compounds as potential key mediators. The plant-plant interactions under study triggered significant molecular changes in specialized metabolism, biotic interactions, transporters, and responses to resources. Disrupting root interactions canceled both the macroscopic and molecular responses, thus providing a strong link between them. These insights provide a deeper understanding of the molecular basis of plant-plant interactions and the processes involved in reducing disease susceptibility in intraspecific mixtures
Flying as a Partnership Towards a Sustainable Future
No full textInternational audienceThis handbook is a practical guide for anyone seeking to build or strengthen partnerships for sustainable food systems. Drawing on real-world cases from across Europe, the handbook offers: step-by-step guidance on establishing inclusive partnerships at local, regional, national, and international levels; tools to mobilise collective intelligence and bring diverse perspectives together; lessons learned from FOODPathS pilots and collaborations. The handbook is a summary of a more exhaustive manual developed by FOODPathS (Deliverable 2.7. Manual; Presentation of the Prototype 2.0 Partnership on Sustainable Food Systems
Beyond Climate Change: The Role of Integrated Soil Fertility Management for Sustaining Future Maize Yield in Sub‐Saharan Africa
No full textInternational audienceClimate change is projected to exacerbate food insecurity in sub‐Saharan Africa (SSA) by reducing crop yields and soil fertility. Many climate change impact studies in SSA have overlooked long‐term effects of soil fertility on crop yield. We evaluated maize yields under different scenarios of soil fertility (using soil organic carbon as a proxy) and climate change (considering changes in temperature, rainfall, and CO2) at four sites in SSA. Using an ensemble of 15 calibrated soil‐crop models, we found a strong consensus that, without fertilization, soil fertility declines over time, impacting maize yields more strongly than changes in temperature, rainfall, or CO2. The model ensemble indicated that when accounting for soil fertility changes, the yield benefits of combined application of organic and mineral inputs increase over time, even under climate change. These findings highlight the importance of considering long‐term change in soil fertility when assessing impacts of climate change and integrated nutrient management on crop production in SSA
Aluminium accumulation in loengo (Anisophyllea boehmii Engl.), a fruit from the Miombo ecoregion consumed in Angola
No full textInternational audienceThe fruit of Anisophyllea boehmii, known as loengo in Angola, is a wild fruit typically harvested in the Miombo forest. It is widely consumed locally and appreciated for its organoleptic qualities. It also has proven nutritional interests. However, analysis of the mineral profile of the fruit pulp using inductively coupled plasma with mass spectrometry (ICP-MS) on 7 samples collected in 3 geographical areas over 3 consecutive years revealed an uncommon aluminium content of around 8 g‧kg-1 of dry matter. Indeed, the concentrations measured in the leaves confirmed that the plant is an aluminium hyperaccumulator. No correlation was found between the aluminium content of the pulp and that in soil. This particularly high value led to the recommendation to limit consumption of the fruit to protect local populations from excessive and repeated exposure to aluminium
Nouvelles formes de travail en agriculture
No full textLe travail agricole se transforme avec l’émergence de nouvelles formes de pratiques, d’organisations et de figures professionnelles. Plurielles, hétérogènes, souvent invisibles, elles demeurent encore largement méconnues. À partir de recherches menées en France, les auteurs analysent ces transformations à l’échelle des pratiques, des conceptions de métiers, des trajectoires des travailleurs et de l’organisation des exploitations. Ils mettent en lumière les dissociations entre terre, capital et travail et les recompositions collectives qu’elles suscitent ; les reconfigurations techniques, normatives et professionnelles ; la diversité des figures des travailleurs, leurs invisibilités et leurs revendications. Cet ouvrage illustre la variété des mutations en cours dans l’agriculture française et rend compte, à travers le prisme du travail, de la réalité quotidienne des activités comme des parcours individuels. Il s’adresse aux chercheurs, enseignants, étudiants et professionnels intéressés par les dynamiques du travail agricole. Coordonné par Nathalie Hostiou, Pierre Gasselin et Benoît Dedieu, zootechniciens et géographe à INRAE, ce livre est le fruit d’une démarche collective réunissant 36 auteurs dans le cadre des activités d’un réseau de chercheurs soutenu par le département ACT (Action, Transitions et Territoires) pendant 4 ans. La préface est signée par Christophe Soulard, géographe, directeur de recherche et chef du département ACT d’INRAE
Perceptual Advantages of People Living in Semeru Volcanic Areas, Indonesia: An MRCV (Multiple Response Categorical Variable) Analysis
No full textInternational audienceWhy populations persist in active volcanic zones poses a fundamental challenge to risk perception models. We propose that perceptual advantages wherein tangible and intangible benefits filtered through local worldviews underpin this resilience. Through a thematic analysis of an open-ended question/answer study of communities in Mount Semeru, Indonesia, we identify six core frameworks of perceptual advantages. Analysis of Multiple Response Categorical Variable (MRCV) reveals that residents of high-risk zones cognitively amplify bio-cultural and livelihood benefits, showing significantly higher odds of emphasizing BIRTH/FAMILY (lineage/kin ties, birthright, and deep social networks that create an intergenerational connection to the land) and ECONOMIC (livelihood opportunities, including agriculture and volcano-driven tourism) advantages, while safe-zone residents prioritize ambient CLIMATE-related benefits (a preferred quality of life attributed to the region’s cool, fresh air and superior air quality). Crucially, the influence of gender is context-dependent, as significant disparities in perception vanish within the high-risk zone. In this environment, the shared experience of chronic volcanic threat supersedes gender distinction to foster a "community of fate". Within this collective, a shared risk-benefit calculus and a unified identity override individual perspectives. These findings demonstrate that persistence in hazardous environments reflects an active cognitive recalibration of risk and benefit, necessitating disaster policies that integrate these perceptual realities
Influence of terroirs on the phenolic composition and astringency of wines made from representative plots of Corbières subregions
No full textInternational audiencePhenolic compounds play a significant role in the organoleptic properties (colour, astringency, and bitterness) and stability of wines through oxidative processes. These properties depend on both intrinsic factors, such as grape variety, and extrinsic ones, such as soil, climate, and winemaking techniques. The Corbières appellation is a renowned red grape variety region of the south of France. This work evaluated the effect of soil, climate, and vineyard practices in this region on the polyphenolic compositions of Syrah, Grenache, Carignan, and Mourvèdre mono-varietal wines produced at an experimental scale from the same vintage. A general and targeted study of the wines' polyphenol profiles was adopted, focusing on anthocyanins, derived pigments, and tannins. The studied regions can be discriminated in terms of some of the analysed parameters depending on grape variety. Moreover, through a Check-All-That-Apply (CATA) sensorial analysis, a link was traced between the tannin composition and the astringency perception of the wines.</div