Biology-Basel最新文献

Orbea is a morphologically diverse lineage within the subtribe Stapeliinae, yet plastome evolution in Arabian taxa remains insufficiently characterized. This study reports the first complete chloroplast genomes of Orbea sprengeri subsp. commutata and O. wissmannii var. eremastrum and investigates plastome structure, sequence variability, and phylogenetic relationships across tribe Ceropegieae. Chloroplast genomes were assembled, annotated, and compared with 13 published plastomes representing major Ceropegieae lineages. Both Arabian plastomes displayed the typical quadripartite structure and identical gene content of 114 unique genes, including 80 protein-coding genes, 30 transfer RNA genes, and four ribosomal RNA genes. However, O. wissmannii var. eremastrum exhibited pronounced structural divergence, possessing the largest plastome recorded for the tribe (170,054 bp), an 8.9 kb expansion of the inverted repeat regions, and an 8.4 kb inversion spanning the ndhG-ndhF region. Comparative analyses revealed conserved gene order across Ceropegieae but identified six highly variable loci (accD, clpP, ndhF, ycf1, psbM-trnD, and rpl32-trnL) as potential DNA barcodes. Selection pressure analyses indicated strong purifying selection across most genes, with localized adaptive signals in accD, ndhE, ycf1, and ycf2. Phylogenomic reconstruction consistently resolved the two Arabian Orbea taxa as a distinct clade separate from the African O. variegata. This study fills a gap in Ceropegieae plastid genomics and underscores the importance of sequencing additional Orbea species to capture the full extent of genomic variation within this diverse genus.

Ketamine (KET) administration protocols vary widely in their design, with acute, sub-chronic, and chronic dosing regimens used to induce psychotic-like behavior in rodent models. This review compares representative classic and contemporary studies employing differing KET administration protocols to model psychosis in laboratory rodents. Specifically, we have focused on the behavioral tasks and analytical methods used to validate KET-induced symptoms of psychosis-like and schizophrenia-like behaviors. While variability in behavioral tasks complicates direct comparisons across studies, these findings provide a framework for selecting dosing strategies aligned with specific research objectives. Acute KET protocols are particularly suited for addiction research or as a preliminary approach preceding longer-term studies. In contrast, protocols utilizing repeated or sub-chronic, or chronic administration of KET tend to yield more comprehensive models of psychosis-like behavior and are better suited for examining the associated enduring cognitive and neurobiological impairments. Administering KET intravenously or intraperitoneally at frequent intervals or with a bolus dose, may sustain higher levels of bioavailable KET, thereby producing a more robust and reliable psychosis-like phenotype, especially relevant for investigations of long-term cognitive and neurological dysfunction.

Current research on glial cells has primarily focused on central nervous system glial cells (CNS glia), with relatively fewer studies on EGCs. Given the critical role of EGCs in maintaining intestinal homeostasis and neural function, this study aimed to investigate their immunomodulatory effects under inflammatory conditions. Primary EGCs were isolated and an inflammatory model was established by treatment with lipopolysaccharide (LPS). Following LPS induction, cellular samples were collected for transcriptomic analysis to identify differentially expressed genes. The analysis revealed that 88 genes were significantly altered, with 60 upregulated and 28 downregulated. Through Gene Ontology (GO) classification, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway mapping, and protein-protein interaction (PPI) network analysis, several key regulatory genes were identified: chemokine-related genes (IL8L2, IL8L1, CCL4, CCL5, and CX3CL1); negative feedback regulation-related genes (TNFAIP3 and ZC3H12A); homeostasis-maintaining genes (C1QB and LY86); and arachidonic acid metabolism-related genes (PTGS2 and GGT2). Under LPS stimulation without impairing EGC viability, EGCs may recruit immune cells by regulating the aforementioned genes. Additionally, arachidonic acid and its metabolites likely play important regulatory roles in EGC-mediated immunomodulation. These findings provide new theoretical insights and potential targets for further elucidating the pathogenesis of intestinal inflammation and developing targeted therapies.

Tea is produced from the fresh leaves of the tea plant (Camellia sinensis), and the quality of tea is directly dictated by its raw material. Although factors such as tea cultivar, fertilization, and cultivation practices are known to affect fresh leaf quality, the specific influence of altitude remains poorly understood. In this present study, ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was employed to investigate the non-volatile metabolites in fresh tea leaves grown at two different altitudes (350 m and 600 m). A total of 2323 metabolites were identified, with flavonoids and phenolic acids representing the dominant classes. Orthogonal partial least squares-discriminant analysis (OPLS-DA) further revealed 116 differential metabolites between groups. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis indicated that several key pathways were differentially activated, including those related to the biosynthesis of kaempferol, luteolin, and flavones, as well as nucleotides and jasmonic acid metabolism. In addition, marked differences were observed in the accumulation patterns of lipids, phenolic acids, and flavonoids between leaves grown at the two altitudes. These findings provide valuable insights into the role of altitude in shaping the metabolic composition and flavor formation of tea.

Age-related osteoporosis is driven in part by senescence-associated rewiring of bone marrow mesenchymal stem cells (MSCs) from osteogenic toward adipogenic fates. Accumulating evidence indicates that epigenetic drift and reduced autophagy are not isolated lesions but are mechanistically coupled through a bidirectional DNA methylation and autophagy axis. Here, we summarize how promoter hypermethylation of genes involved in autophagy and osteogenesis suppresses autophagic flux and osteoblast lineage transcriptional programs. Conversely, autophagy insufficiency reshapes the methylome by limiting methyl donor availability, most notably S-adenosylmethionine (SAM), and by reducing the turnover of key epigenetic regulators, including DNA methyltransferases (DNMTs), ten-eleven translocation (TET) dioxygenases, and histone deacetylases (HDACs). This self-reinforcing circuitry exacerbates mitochondrial dysfunction, oxidative stress, and inflammation driven by the senescence-associated secretory phenotype (SASP), thereby stabilizing adipogenic bias and progressively impairing marrow niche homeostasis and bone remodeling. We further discuss therapeutic strategies to restore balance within this axis, including selective modulation of epigenetic enzymes; activation of AMP-activated protein kinase (AMPK) and mechanistic target of rapamycin (mTOR) signaling with downstream engagement of Unc-51-like autophagy-activating kinase 1 (ULK1) and transcription factor EB (TFEB); targeting sirtuin pathways; mitochondria- and autophagy-supportive natural compounds; and bone-targeted delivery approaches or rational combination regimens.

Paralytic shellfish toxins (PSTs) are produced by several toxic species of the dinoflagellate genera Alexandrium and Gymnodinium, and they pose significant threats to marine ecosystems and public health. Rapid and accurate detection of harmful algal blooms (HABs) is essential for effective management. In this study, we developed a multiplex quantitative real-time PCR (qPCR) assay targeting the 28S ribosomal DNA region to simultaneously detect three PST-producing dinoflagellates, Alexandrium catenella, A. pacificum, and Gymnodinium catenatum, in the East China Sea off southern Korea. Species-specific primers and hydrolysis probes labeled with distinct fluorophores were validated for simultaneous detection. The standard curves showed strong linearity (R² > 0.99) and high amplification efficiencies (95.268-99.325%). No cross-reactivity was observed among the 20 non-target microalgal species. Field application of the assay using environmental DNA (eDNA) samples collected during spring successfully detected A. catenella and A. pacificum, whereas G. catenatum was not detected during the survey period. This multiplex qPCR assay provides a rapid and reliable molecular tool for early detection and spatial monitoring of potentially PST-producing dinoflagellates, supporting sustainable HAB management in East Asian coastal ecosystems.

The flavivirus NS1 protein is a component of the viral replication complex and plays diverse, yet poorly understood, roles in the viral life cycle. To enable real-time visualization of the developing replication organelle and biochemical analysis of tagged NS1 and its interacting partners, we engineered a replication-competent yellow fever virus (YFV) replicon encoding a C-terminal fusion of NS1 with green fluorescent protein (NS1-GFP). The initial variant was non-viable in the absence of trans-complementation with wild-type NS1; however, viability was partially restored through the introduction of co-adaptive mutations in GFP (Q204R/A206V) and NS4A (M108L). Subsequent cell culture adaptation generated a 17-nucleotide frameshift within the NS1-GFP linker, resulting in a more flexible and less hydrophobic linker sequence. The optimized genome, in the form of a replicon, replicates in packaging cells that produce YFV structural proteins, as well as in naive BHK-21 cells. In the packaging cells, the adapted NS1-GFP replicon produces titers of infectious particles of approximately 10⁶ FFU/mL and is genetically stable over five passages. The expressed NS1-GFP fusion protein localizes to the endoplasmic reticulum and co-fractionates with detergent-resistant heavy membranes, a hallmark of flavivirus replication organelles. This NS1-GFP replicon provides a novel platform for studying NS1 functions and can be further adapted for proximity-labeling strategies aimed at identifying the still-unknown protease responsible for NS1-NS2A cleavage.

In this study, the osteoinductive activity of a small-molecule NOTCH1 activator, Yhhu3792, and Poloxamer 407, an FDA-approved hydrogel, was evaluated independently regarding osteoblast functions in vitro using primary cultures of osteoblasts derived from C57BL/6J mice. We found that treatment with Yhhu3792 increased the number of NOTCH1-positive osteoblasts (36%) compared to the vehicle control (19%) after antibody staining, suggesting increased NOTCH1 signaling after Yhhu3792 treatment. Osteoblasts treated with varying doses (5, 10, and 20 μM) of Yhhu3792 and P407 (1-25%) stimulated both osteoblast proliferation and differentiation by 25-45% (p < 0.05) compared to the vehicle control. Accordingly, 10 µM Yhhu3792 treatment for 9 days increased the alizarin red-stained mineralized nodule area (8.69 ± 0.97 vs. 4.05 ± 1.51 arbitrary units; p < 0.05) compared to the vehicle treatment. Similarly, osteoblasts treated with 10% P407 also significantly increased mineralized nodule formation. The Cell Tox Green dye assay revealed that the dosage of Yhhu3792 used was not cytotoxic. Gene expression studies measured by real-time PCR revealed that a 24 h treatment with 10 µM Yhhu3792 significantly increased expression levels of bone formation markers (Vegf, Osteocalcin) and NOTCH1 targets (c-myc, Cox2, and Hes1) in osteoblasts. A low dose of P407 in combination with 10 µM Yhhu3792 stimulated a significant increase (>40%) in the proliferation of bone marrow stromal cells. In conclusion, our in vitro findings showing osteogenic effects of the small molecule Yhhu3792 and P407 hydrogel should be confirmed in vivo in animal fracture healing models.

Vibriosis, caused by diverse Vibrio species, is among the most devastating bacterial diseases in shrimp aquaculture. Consequently, breeding shrimp for pan-vibrios resistance (PVR) presents a crucial strategy for sustainable shrimp farming. In this work, we performed a GWAS in Litopenaeus vannamei to identify genetic loci underlying resistance to pan-vibrios and validate the identified SNPs. A total of 300 shrimp from nine different regions were subjected to a comprehensive challenge. Selective genotyping of 300 resistant and susceptible individuals was conducted using a specific length amplified fragment sequencing (SLAF-seq) approach. A total of 18,184,608 high-quality SNPs were detected across the whole genome of L. vannamei. Screening identified 283 SNPs located within genes, 26 of which were associated with the PVR trait. These SNPs were subsequently validated in verification group of 80 shrimps, leading to the identification of two genotypes (GG at SNP20 and AA at SNP21) and one genotype combination (GG/AA at SNP20 and SNP21) that were significantly associated with the PVR trait. Notably, these linked SNPs were identified in the intron of LvHEATR1 gene. The highest LvHEATR1 expression was observed in immune-related tissues including hemocytes, the gills, and the hepatopancreas. Furthermore, qPCR results showed that LvHEATR1 expression was significantly higher in the vibrios-resistant (RES) group than in the vibrios-susceptible (SUS) group. This study proposed the PVR concept and provided valuable molecular markers for the genetic improvement of vibrios-resistance in L. vannamei.

Cadmium (Cd) contamination in agricultural systems poses significant ecotoxicological risks through bioaccumulation in food chains. While lime-based amendments are widely applied for Cd immobilization, mechanistic understanding of bioavailability control pathways remains limited. This study employed a meta-analysis methodology based on 260 datasets from 55 publications to systematically investigate the mechanisms and differences in the effectiveness of calcium hydroxide, calcium carbonate, and calcium oxide in regulating Cd migration in acidic soil-plant systems. The study revealed that lime-based materials synergistically regulated Cd migration through two processes: chemical fixation and ionic competition. Results showed lime application reduced soil available Cd by 33.0%, decreased grain Cd by 44.8%, increased soil pH by 15.6%, and enhanced exchangeable Ca by 35.2%. Chemical fixation was evidenced by Cd transformation from labile to stable forms (residual Cd: +29.5%, acid-soluble Cd: -17.5%). Ionic competition was quantitatively confirmed through strong negative correlation between exchangeable Ca and grain Cd (R² = 0.704). Among the materials, Ca(OH)₂ exhibits the highest efficiency in rapid pedogenic passivation (58.7% reduction in available Cd), whereas CaCO₃ demonstrates superior long-term grain Cd attenuation (65.7% inhibition) via sustained Ca²⁺ release and rhizosphere-regulated dissolution. This study advances mechanistic understanding of Cd bioavailability control and establishes quantitative frameworks for predicting ecotoxicological outcomes, providing scientific basis for optimizing remediation strategies to minimize Cd transfer through agricultural food chains.