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Effects of nitrogen allocation and photosynthetic proteins response in peanut leaves on photosynthesis under conditions of water scarcity and nitrogen deficiency.

Leaf nitrogen allocation and photosynthetic proteins response can affect net photosynthetic rate (Pn), ultimately influencing crop yield under diverse environmental stresses. However, the internal relationship between Pn with leaf nitrogen allocation and photosynthetic proteins response under nitrogen or water scarcity in peanut (Arachis hypogaea L.) remains elusive. Here, comprehensive physiological property and proteomic analyses of peanut were conducted, revealing that both nitrogen and water scarcity remarkably impeded leaf growth and reduced Pn. Nitrogen deficiency significantly reduced the total nitrogen content per unit leaf area (Narea), chlorophyll content, and Pn, whereas drought stress caused a greater decline in photosynthetic nitrogen use efficiency (PNUE). The allocation of leaf nitrogen to photosynthetic components, including the carboxylation system and electron transport system in leaves, was significantly reduced when subjected to individual or combined deficiency. Proteomic analyses exhibited that several key photosynthetic proteins underwent a decrease under both single and combined water and nitrogen deficiency conditions. Thereby, Pn may decline due to the disruption of nitrogen allocation and down-regulated expression of photosynthetic proteins under these stress conditions. Our findings establish a benchmark for future research exploring the roles of leaf nitrogen allocation and photosynthetic proteins in the plant's response to nitrogen or water deficiency.

Nitrogen

Integrative omics of the genetic basis for wheat WUE and drought resilience reveal the function of TaMYB7-A1.

Improving wheat drought resilience and water use efficiency (WUE) is critical for sustaining productivity under increasing water scarcity. Here, we integrate genome-wide association study (GWAS), expression quantitative trait locus (eQTL) mapping, population-transcriptome analysis, and summary-data-based mendelian randomization (SMR), followed by functional validation using indexed EMS mutants and transgenic lines, to systematically identify key WUE regulators. GWAS across water conditions in 228 accessions identifies 73 quantitative trait loci (QTLs) for WUE-traits. Transcriptome profiling of 110 diverse accessions reveals 28 drought-responsive modules. eQTL mapping uncovers 146,966 regulatory variants, including condition-specific hotspots associated with key drought-related pathways. Integrative analysis underscores 85 high-confidence candidate genes, notably TaMYB7-A1. Overexpression of TaMYB7-A1 enhances photosynthesis, WUE, root development, and grain yield under drought condition by activating TaPIP2;2-B1 (water transport), TaRD20-D1 (stomatal regulation), and TaABCB4-B1 (root growth), reflecting reduced water loss and improved physiological resilience. Our study presents a comprehensive regulatory map and robust targets for wheat drought adaptation and resilient cultivar breeding.

Triticum

Features of cholera and Vibrio parahaemolyticus diarrhoea endemicity in Calabar, Nigeria.

The clinical and epidemiological features of acute vibrio diarrhoeal disease were studied in 881 patients seen at the University of Calabar Teaching Hospital (UCTH), Calabar, Nigeria, between January and December 1989. Stools and rectal swabs of patients and randomly-selected control subjects were microscopically and culturally examined for the presence of enteric pathogens. Households of vibrio diarrhoea cases and matched controls were visited for ecologic studies. Of a total of 108 (12.3%) culturally-confirmed bacterial diarrhoeas, 47 (43.5%) were due to Escherichia coli, 33 (30.6%) to Vibrio cholerae-01 (classical and El Tor biotypes) and V. parahaemolyticus, while shigellae and salmonellae accounted for 29 (26.9%) and 9 (8.3%) cases, respectively. Most cholera case households clustered within the ancient neighbourhood of the inner city, characterized by poorly developed water and sewage disposal systems. A preponderance of vibrio diarrhoea patients were children < or = 10 years. Adult cases involved mostly females. The only case of diarrhoea-related death involved an eight-month old child with kwashiorkor and V. parahaemolyticus infection. Incidence of vibrio diarrhoeas was seasonal, with most cases occurring during the dry season followed by subsidence at the onset of rainy season. Bimodal peaks of vibrio diarrhoeal episodes observed over the period appeared to coincide with periods of acute water scarcity, high temperature, increased fishing activities and trade traffic on the Calabar River estuary. Of the environments sampled, only clam shells from a case household and river sediments yielded vibrio pathogens on culture. Ecological factors that are capable of stabilizing a focus of vibrio diarrhoea endemicity in this area are highlighted.

Adolescent

Chromosome-scale genomes and population resequencing resolve subgenome diversity and halophyte adaptation in Salicornia.

Amid escalating water scarcity and groundwater depletion, halophytes such as Salicornia (Amaranthaceae) represent valuable models for extreme salt tolerance and hold promise for saltwater-based agriculture. Here, we show chromosome-scale genome assemblies for six Salicornia species, revealing four distinct subgenomes, reconciling our assemblies with two existing reference genomes (S. ramosissima UK and S. europaea China), correcting chromosome numbering and orientation. Comparative analyses across ploidy levels demonstrate genome expansion in North American lineages driven by Gypsy retrotransposons, and lineage-specific expansions of two gene families implicated in stress metabolism. Phylogenetic and population-structure analyses of a global resequencing panel of 318 accessions resolve interspecific relationships and establish curated germplasm collections for future crop breeding. Genetic analyses uncover a contrasting population-genetic signal on chromosome 6A between two species, highlighting an OSCA&#xa0;calcium-permeable channel gene as&#xa0;a candidate locus for osmotic adaptation. Together, these resources establish a genomic framework for Salicornia that supports evolutionary studies of halophyte adaptation and crop development.

Chenopodiaceae

Sympatric European white oaks species display contrasting epigenetic response to soil water availability.

In the context of climate change plants have to cope with adverse conditions, among which water scarcity is a major threat for their survival. They have developed diverse regulatory processes to face drought that may differ depending on their ecological niche. The two sympatric oaks species (Quercus robur L. and Quercus petraea (Matt.). Liebl) have different levels of drought tolerance. We have investigated their strategies to face drought stress by analysing the transcriptome, small RNAome and methylome dynamics of young plants grown under control and drought stress conditions. Data indicate that cell wall remodeling is most likely involved in the better tolerance Q. petraea than of Q. robur. Furthermore, major methylation differences were identified between both oak species that were in part associated to their difference in drought stress responses. Integration of the three datasets revealed genomic co-locations of potential importance for forest tree adaptation to drought stress. Our data are consistent with species-specific molecular responses of oak to drought stress related to their ecological niches.

Forest trees- Omics- ecological niche

Comparative analysis of DREB gene family in buckwheat: the role of FtDREB02 in the delphinidin biosynthesis and drought stress response.

Dehydration response element binding (DREB) transcription factors play a pivotal role in plant abiotic stress responses, but its evolutionary and functional characterization in buckwheat remains unexplored. Here, we conducted a comprehensive analysis of the DREB gene family across three buckwheat species, revealing segmental duplication as the primary driver of family expansion and potential purifying selection during evolution. A FtDREB02 gene, classified as group A2, was identified through genome-wide association analysis (GWAS) on drought tolerance and delphinidin content. Functional validation in Arabidopsis thaliana and the hairy root of Tartary buckwheat (Fagopyrum tataricum) demonstrated that overexpression of this gene promotes delphinidin biosynthesis and enhances plant resistance to water scarcity. Through the integration of DAP-seq and PEG transcriptome cluster analysis, a FtANS candidate was screened. Functional studies showed that FtDREB02 regulates delphinidin content by binding directly to DRE elements of the FtANS promoter. This research identifies and comprehensively analyzes the DREB family within buckwheat species, elucidating the regulatory mechanisms of FtDREB02 in controlling flavonoid biosynthesis and drought resistance, providing potential genetic resources for breeding buckwheat varieties with excellent agronomic traits.

Anthocyanins

Spore-forming Clostridia as overlooked determinants of microbial risk in wastewater reuse systems.

Using treated municipal wastewater for crop irrigation is a key strategy to combat drought-induced water scarcity. However, current wastewater reclamation standards systematically underestimate risks from spore-forming pathogens. As highlighted in a recent minireview by A. Mrozinski, C. Le Mar&#xe9;chal, and E. Topp in Applied and Environmental Microbiology (92:e00173-26, 2026, https://doi.org/10.1128/aem.00173-26), Clostridioides difficile and Clostridium perfringens survive conventional disinfection, persist indefinitely in agricultural soils, and harbor critical antibiotic resistance genes. To safeguard the food supply and protect public health, regulatory frameworks must shift from relying solely on standard vegetative bacterial indicators and include monitoring resilient, spore-forming pathogens.

Clostridium

Morphology of the gills of larval and parasitic adult sea lamprey, Petromyzon marinus L.

The general morphology of the gills is similar in larval (ammocoetes) and parasitic adult sea lampreys, Petromyzon marinus, despite different methods of ventilation necessitated by their feeding habits. The gill lamellae are supported by randomly-distributed pillar cells which enclose blood spaces and collagen columns. The distribution of these cells in lampreys is different from that of higher fishes and it may be inefficient for respiratory exchange. The presence of cytoplasmic microfilaments suggests that these cells have the ability to reduce the lamellar blood spaces through contraction. Marginal channels at the tips of the lamellae are lined only by endothelial cells. The thickness of the water-blood pathway in lampreys falls within the range described for higher fishes, with the most efficient gas exchange likely occuring at the lamellar tips where only a single layer of epithelial cells is present. The abrupt increase in height of the epithelium near the lamellar bases in adults, compared to the gradual transition in height along the lamellae in ammocoetes, is perhaps reflective of higher oxygen requirements during the parasitic stage. The consistent appearance of wide, lateral intercellular spaces within the respiratory epithelium of lampreys indicates possible involvement of these spaces in transport. Mucous secretion appears to be an important function of the superficial platelet cells in ammocoetes. "Mitochondria-rich" and "mitochondria-poor" superficial cells are observed in both ammocoetes and adults, with the mitochondria-rich cells more prevalent toward the lamellar bases. The possibility that at least some of these cells may be involved in absorption is discussed. Mitochondria-rich cells in the interlamellar region are morphologically different in ammocoetes and adults but all possess an abundance of smooth endoplasmic reticulum and hence resemble "chloride cells" of higher fishes. The similarity of these cells in the parasitic adult lamprey to chloride cells of marine fishes may reflect the potential of the adult lamprey to osmoregulate in salt water. A scarcity of these cells in ammocoetes and their resemblance to chloride cells in freshwater fishes may reflect the restriction of larval lampreys to a freshwater habitat.

Animals

Desalinated water hygiene and scientific bases for its investigation.

In view of the increasing scarcity of fresh water reserves in many countries of the world, a thorough hygienic evaluation of the different methods of desalinating highly mineralized underground and sea waters for economic and drinking purpose becomes indispensable. In addition to generally accepted hygienic criteria (favourable organoleptic properties, innocuous chemical composition and epidemiological safety), introduction of supplementary criteria for the assessment of the characteristic of the quality of freshened drinking water is necessary, i.e., its full value in the physiological sense and stability of drinking properties. The necessity of hygienic tests concerned with the study and regulation of the mineral and microelement composition of desalinated drinking water as well as of its microbial composition, structural peculiarities, the so-called "deuterium number" and the presence of various organic substances in desalinated water was pointed out. A certain degree of priority should be given to the study of the mentioned indices in hygienic assessment of the different methods of water desalination (distillation, freezing out, ion exchange, electrodialysis, inverse osmosis and others).

Hygiene

Fine structure of the interplatelet area in the gills of the macrophthalmia stage of the river lamprey, Lampetra fluviatilis (L.).

The interplatelet epithelium of the gills of freshwater and seawater adapted macrophthalmia stages of the river lamprey, Lampetra fluviatilis, was studied by electron microscopy. Three main cell types: basal, ion-excretory and superficial cells were identified and described. Ion-excretory cells were exposed to the environment in sea water but covered by a layer of superficial cells in fresh water. Electron-dense secretory granules in the apex of the cell were more abundant in fresh water. In fresh water, a few of the superficial cells contained numerous mitochondria and were identified as ion-uptake cells. In view of the scarcity of ion-uptake cells, the possibility that the ion-excretory cells are also responsible for ion-uptake in fresh water is discussed. Phagocytic removal of degenerating ion-excretory cells may be an important mechanism for the conservation of materials in a starving animal.

Animals

Analyzing salinity tolerance in grass carp (Ctenopharyngodon idella): Insights from genome-wide association study and genomic selection.

Grass carp (Ctenopharyngodon idella) is one of the most widely cultured freshwater fish species globally. However, the expansion of its farming scale faces severe limitation owing to freshwater scarcity; therefore, the development of strains with greater salinity tolerance is key for expanding production using brackish water resources. To investigate the genetic basis of salinity tolerance in grass carp, a genome-wide association study (GWAS) was conducted using 200 individuals representing extreme phenotypes, namely salinity-tolerant and salinity-sensitive groups. In total, 17 single nucleotide polymorphisms (SNPs) related to salinity tolerance were detected, which were distributed across 11 chromosomes. Through gene annotation, 38 candidate genes were obtained from these loci. Enrichment analysis revealed these candidate genes are primarily implicated in key biological processes, including osmotic regulation, energy metabolism, and stress responses. Analyses of different SNP densities revealed that the 5&#xa0;K SNP density panel can balance prediction accuracy and computational efficiency. The BayesA model achieved the highest prediction accuracy under the GWAS_Evenly selection strategy, with substantial reductions in mean absolute error and mean square error. This study reveals the genetic mechanisms of salinity tolerance in grass carp, which might be optimized through genomic selection, and provides insights for selectively breeding new varieties with greater salinity tolerance.

Animals

Increased precipitation decelerates temporal succession of grassland soil microbial communities.

Global precipitation regimes have been shifted in recent decades, imposing significant consequences in water-limited grassland ecosystems. However, the effects of increased precipitation on the succession of soil microbial communities remain unclear, mainly due to the scarcity of long-term experiments with time-series data. Here, we examined temporal succession of grassland soil microbial communities in a long-term increased precipitation experiment. Both soil microbial taxonomic and functional structures were significantly altered by increased precipitation. Increased precipitation significantly decelerated the succession rates of soil microbial functional structure (i.e. time-decay relationships). Consistent with the increased microbial decomposition and heterotrophic respiration, the abundances of soil microbial carbon decomposition genes were markedly enhanced by increased precipitation. Furthermore, increased precipitation stimulated genes involved in nutrient cycling processes, potentially promoting plant growth. Collectively, the contributions of stochastic processes in shaping microbial communities were increased under increased precipitation, suggesting that microbial successional trajectories may shift toward multiple alternative states characterized by greater stochasticity under future altered precipitation regimes.

Soil Microbiology

The use of hetastarch for plasma expansion.

The use of colloids in hypo-oncotic individuals to increase plasma volume has been shown to have distinct and consistent advantages compared with the use of crystalloid fluids. Colloids increase plasma colloid oncotic pressure, whereas crystalloids decrease it, an effect that can be extremely detrimental in individuals with low basal plasma colloid oncotic pressure. Increasing plasma volume in hypo-oncotic individuals without inducing large increases in interstitial water content is difficult when crystalloid fluids are used. However, colloids have much better plasma volume expansion ability without the induction of concurrent increases in interstitial water content, even in hypooncotic individuals. Review of the literature indicates that hetastarch is an extremely safe colloid for acute and long-term use in humans and dogs. Its excellent safety record probably is attributable to its structural analogy to the natural compound glycogen. The lack of availability of a substance analogous to human 5% serum albumin and the scarcity of plasma in veterinary medicine leaves hetastarch as the safest option of available colloids. Its ability to increase plasma volume and colloid oncotic pressure is equal to or better than dextran 70 and 5% albumin and is clearly better than plasma or whole blood. Increases in plasma volume and colloid oncotic pressure usually last approximately 48 hours after a single injection, but the duration of increases significantly after multiple infusions. Contraindications to its use include heart failure and oliguric renal failure, because of its excellent ability to increase plasma volume, and the presence of von Willebrand's disease, because of its ability to significantly lower all components of Factor VIII-related complex in humans.

Animals

Deep subsurface organic-rich shale supports abundant, diverse, and novel fungi.

As Earth's principal reservoir of organic carbon and microbial biomass, the deep subsurface hosts microorganisms capable of mobilizing this once-sequestered carbon. Contrary to standard assumptions of eukaryotic scarcity, this study documents abundant fungal communities, ranging from 4.2&#x2009;&#xd7;&#x2009;103 to 6.8&#x2009;&#xd7;&#x2009;103 fungal cells ml-1, across a methane-producing organic-rich shale 247-556 meters below the surface. Although fungal:bacterial cell ratios ranged from 1:7028 to 1:713, application of biomass conversion factors developed for oceanic systems yielded a median fungal:bacterial biomass ratio of 1:4.7. 16S ribosomal ribonucleic acid (rRNA) gene amplicons revealed bacterial and archaeal communities mirroring those found in well-characterized extremophilic, carbon-degrading environments, while sequencing of 18S rRNA gene and internal transcribed spacer rRNA spacer amplicons collectively identified a eukaryotic hotspot with 689 fungal operational taxonomic units across six phyla. The dominant fungal classes, Agaricomycetes and Dothideomycetes, are well-established degraders of recalcitrant carbon compounds at the surface, suggesting they may similarly contribute to organic matter degradation and ecosystem maintenance in the subsurface. Cultivation and isolation efforts yielded 205 fungal strains, including 13 candidate novel taxa, underscoring the deep subsurface as an underexplored eukaryotic habitat. Stable carbon isotopes indicate methane is predominantly generated via microbial conversion of the fossil carbon, while water isotopes suggest in situ geochemical conditions have been relatively stable since the Late Pleistocene, with subglacial recharge as a plausible mechanism for microbial introduction. Collectively, these findings suggest that fungi are underrecognized contributors to organic matter transformation and functional diversity in the deep biosphere, revealing a critical gap in our understanding of deep subsurface ecosystem processes.

Fungi

Age as a function in the development of sodium-related hypertension.

The populations of the developed nations of the world exhibit an increase in blood pressure with age, while in primitive societies blood pressure remains relatively constant throughout adult life. Hypertension may be a complex of diseases all having the same clinical manifestations but not being caused necessarily by the same factors. A possible common denominator in the development of any chronic elevation of blood pressure is the need for the kidney to increase urine volume to promote sodium excretion and, thereby, prevent a chronically expanded extracellular fluid (ECF). Hypertension may be viewed as a maladaptation of the body in its attempt to maintain homeostasis of the ECF. Man evolved under conditions of relative scarcity of salt and even now can maintain normal body function with an intake of less than 2 g/day. The high risk person appears to have a hereditary predisposition to a rise in blood pressure in the presence of a high sodium (NaCl) intake. Actually, the degree of rise in blood pressure may be an interaction between the amount of genetic predisposition and the level of sodium and its relation to potassium intake. Recent work in two Massachusetts communities supports this interpretation and suggests that differences in blood pressure distribution may increase with age between a higher and lower sodium community.

Adolescent

TNIK Overexpression Is Sufficient for Chemoradiation Resistance in Limited-Stage Small Cell Lung Cancer.

Small cell lung cancer (SCLC) is characterized by early metastasis, intrinsic chemoradiation resistance, and tumor recurrence. Besides the lack of potentially targetable oncogenic drivers, therapeutic advancements are also hindered by the scarcity of surgically resected tissue specimens ideal for profiling studies. We used patient-derived xenografts (PDX) to model SCLC chemoradiation resistance and identified chemoradiation resistance candidate genes using RNA sequencing. Additionally, we used human SCLC cell lines to confirm our in vivo results and delineate the underlying mechanism. Transcriptome profiling showed that the Traf2- and Nck-interacting kinase (TNIK) gene was consistently upregulated in an array of SCLC PDXs exposed to chemoradiation compared with monotherapy, which is consistent with previous observations of TNIK amplification in human samples. Genetic depletion (P < 0.01) or pharmacologic inhibition (P < 0.0001) of TNIK reduced in vitro clonogenic survival of TNIKhigh SCLC cells and promoted sensitivity to chemoradiation. In vivo, pharmacologic inhibition of TNIK enhanced chemoradiation sensitivity (P < 0.0001) of the H446 cell line-derived xenograft (CDX) in NOD-SCID mice. Furthermore, pharmacologic inhibition of TNIK in vivo demonstrated sensitivity (P < 0.0001) to chemoradiotherapy (CRT) in LX33 PDX. These results indicate that TNIK plays a role in conferring resistance to chemoradiation in SCLC cell lines and in vivo in SCLC CDX and PDX models. Delineating the mechanism behind radiosensitization suggested that TNIK inhibition may impair the DNA damage response in irradiated cells. Collectively, these findings suggest that TNIK may be a promising therapeutic target in limited-stage SCLC and support further investigation of TNIK inhibition in combination with standard CRT.

Humans