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Optimizing thiamine pyrophosphate metabolism enhances crop yield and quality
No full textGlobal food security requires sustainable strategies to improve crop yield and nutrition. Although thiamine pyrophosphate (TPP), the active form of vitamin B1, plays a central role in energy metabolism, redox homeostasis, and carbon assimilation, its contribution to crop yield and quality remains largely unexplored. Here, we show that ZmTPK2, a thiamine pyrophosphokinase encoded by the major ear length QTL qKB6.2a, is a key regulator of maize yield. We reveal that ZmTPK2-dependent TPP homeostasis synchronizes three cornerstones of plant metabolism: mitochondrial tricarboxylic acid (TCA) cycle activity, chloroplast-mediated carbon fixation, and nitrogen utilization. Both overexpression and knockout of ZmTPK2 disrupt yield and grain quality, revealing that optimal TPP levels are required for productivity. Exogenous TPP supplementation increases grain yield in maize, rice, and rapeseed up to 9.8%. These findings identify TPP metabolism as a key regulatory pathway for metabolic engineering, biofortification, and global food security solutions
Genetic architecture of the tomato fruit lipidome
No full textThe lipid composition of tomato (Solanum lycopersicum L.) fruit plays a crucial role in determining fruit quality, nutritional value, and the biosynthesis of key volatile organic compounds (VOCs). Despite this importance, the metabolic diversity and genetic regulation of lipid composition in tomato fruit remain poorly understood. Here, we performed a genome-wide association study (GWAS) and QTL mapping for fruit lipid content from 550 tomato accessions and 107 backcross inbred lines (BILs) in two consecutive seasons. Over 130 lipid compounds were identified in the population, allowing for the identification of over 600 metabolic QTL (mQTL). We further described and validated candidate genes associated with lipid content. Among them is a lipase-like protein (TomLLP) whose function was validated in vivo using overexpression lines in tomato and knockout mutants in Arabidopsis. We also identified functions for three enzymes: a class III lipase (Sl-LIP8), a cyclopropane-fatty-acyl-phospholipid synthase (CFAPS1), and Lipoxygenase C (TomLoxC). By utilizing knockout lines for CFAPS1 and CRISPR-Cas9 loss-of-function lines for Sl-LIP8 and TomLoxC, we demonstrated the functional importance of these enzymes in fruit lipid metabolism. Our study provides a comprehensive analysis of the tomato fruit lipidome and insights into key genes that shape natural variation in lipid content, establishing a framework for exploring how lipid dynamics may influence traits such as flavor and volatile formation
From "Gig" to Genes: The enduring legacy of Seymour Levine in developmental stress neurobiology
No full textThe concept that early life experiences profoundly program adult physiology and behavior is now a cornerstone of neurobiology, a paradigm shift largely founded on the visionary work of Seymour "Gig" Levine. This review traces the intellectual lineage from Levine's pioneering behavioral and physiological studies to the modern molecular era, underscoring his indispensable contribution to understanding developmental stress. Levine's initial elegant experiments established the critical regulatory role of maternal care and the hypothalamic-pituitary-adrenal (HPA) axis, culminating in the discovery of the Stress Hyporesponsive Period (SHRP)-a crucial, sensitive window for developmental programming. Building on this legacy, subsequent research, including my own, has utilized advanced molecular tools to bridge the gap from these macroscopic observations to precise mechanistic detail. I highlight the role of gene-by-environment (G x E) interactions, particularly involving HPA axis modulators like FKBP51 and CRH signaling, in shaping vulnerability. Furthermore, I discuss how Levine's implicit recognition of individual differences has evolved into a central focus on biological sex differences, the match/mismatch hypothesis of adaptive programming, and the use of deep phenotyping to unravel the molecular bases of resilience and vulnerability. Ultimately, the journey from "Gig" to "Genes" provides a foundational understanding that is crucial for developing effective, targeted strategies to promote mental health and resilience across the lifespan
Late Holocene vegetation dynamics, fire regimes, and human impact in Southern Brazil: a multi-proxy palaeoecological record from the Matematico Lake
No full textThe long-term interactions between forest and grassland in Southern Brazil remain poorly understood, despite the region's ecological importance and the ongoing debate about natural versus anthropogenic drivers of landscape dynamics. In this study we present a multi-proxy palaeoecological study of the Matematico sediment core from the Southern Brazilian highlands, with the aim of disentangling the roles of climate and human activity in shaping late Holocene Araucaria Forest and Campos (grassland) dynamics. We combined pollen, non-pollen palynomorphs (NPPs), charcoal, and compound-specific hydrogen isotopes (δ2H) from leaf-wax n-alkanes, making this the first study in Southern Brazil to integrate these proxies within a single core. Between ∼3.500 and 2.100 cal yr BP (calibrated years before present), the landscape was dominated by Campos under relatively dry conditions, with low fire activity and limited forest cover. Subsequent Araucaria Forest expansion happened in two phases, which were identified at ∼1700 and ∼ 500 cal yr BP. Both phases correspond with shifts to more negative δ2H values, indicating a forest expansion due to wetter climatic conditions. However, the earlier wet phase, corresponding to the wettest interval of the last 8000 years in Southern Brazil, did not trigger lasting forest establishment, suggesting that climate alone was insufficient to drive large-scale forest expansion. Meanwhile, the later expansion at ∼500 cal yr BP a coincides with increased charcoal influx and archaeological evidence of intensived occurrence of Southern Jê groups of the Taquara/Itararé Tradition, suggesting potential human influence in this latter expansion. This integrated multi-proxy approach provides new insights into the ecological and cultural legacies of the today's threatened Araucaria Forest–Campos mosaic.1. Introduction 2. Study area 2.1. Geographical setting 2.2. Climate 2.3. Vegetation 2.4. Human settlements 3. Material and methods 3.1. Sampling 3.2. Radiocarbon dating 3.3. Pollen, NPP and charcoal analyses 3.4. Leaf-wax n-alkanes 3.5. Statistical analysis 4. Results 4.1. Chronology and stratigraphy 4.2. Pollen/ NPP/ charcoal data 4.2.1. MA-Ia (80–56 cm, 3680–2340 cal yr BP, 7 subsamples) 4.2.2. MA-Ib (54–46 cm, 2170–1390 cal yr BP, 5 subsamples) 4.2.3. MA-Ic (44–32 cm, 1230–420 cal yr BP, 7 subsamples) 4.2.4. MA-IIa (30–12 cm, 300–90 cal yr BP, 10 subsamples) 4.2.5. MA-IIb (10–4 cm, 60 – (−10) cal yr BP, 4 subsamples) 4.3. Compound-specific hydrogen isotopes (δ2H) from leaf-wax n-alkanes 4.4. Interpretation and discussion 5. Conclusion
Bower visitation patterns of resident and subordinate male Spotted Bowerbirds (Chlamydera maculata) via GPS tracking
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Arboviruses manipulate rice’s volatile emissions, protecting insect vectors from natural enemies in the field
No full textPublisher Correction: The Newtonian limit of orthonormal frames in metric theories of gravity
No full textWe extend well-known results on the Newtonian limit of Lorentzian metrics to orthonormal frames. Concretely, we prove that, given a one-parameter family of Lorentzian metrics that in the Newtonian limit converges to a Galilei structure, any family of orthonormal frames for these metrics converges pointwise to a Galilei frame, assuming that the two obvious necessary conditions are satisfied: the spatial frame must not rotate indefinitely as the limit is approached, and the frame's boost velocity with respect to some fixed reference observer needs to converge