Tea is one of the three most popular nonalcoholic beverages globally and has extremely high economic and cultural value. Currently, the classification, taxonomy, and evolutionary history of the tea family are largely elusive, including phylogeny, divergence, speciation, and diversity. For understanding the evolutionary history and dynamics of species diversity in Theaceae, a robust phylogenetic framework based on 1785 low-copy and 79,103 multi-copy nuclear genes from 91 tea plant genomes and transcriptome datasets had been reconstructed. Our results maximumly supported that the tribes Stewartieae and Gordonieae are successive sister groups to the tribe Theeae from both coalescent and super matrix ML tree analyses. Moreover, in the most evolved tribe, Theeae, the monophyletic genera Pyrenaria, Apterosperma, and Polyspora are the successive sister groups of Camellia. We also yield a well-resolved relationship of Camellia, which contains the vast majority of Theaceae species richness. Molecular dating suggests that Theaceae originated in the late L-Cretaceous, with subsequent early radiation under the Early Eocene Climatic Optimal (EECO) for the three tribes. A diversification rate shift was detected in the common ancestors of Camellia with subsequent acceleration in speciation rate under the climate optimum in the early Miocene. These results provide a phylogenetic framework and new insights into factors that likely have contributed to the survival of Theaceae, especially a successful radiation event of genus Camellia members to subtropic/tropic regions. These novel findings will facilitate the efficient conservation and utilization of germplasm resources for breeding cultivated tea and oil-tea. Collectively, these results provide a foundation for further morphological and functional evolutionary analyses across Theaceae.

Background: Theaceae, comprising 300 + species, holds significance in biodiversity, economics, and culture, notably including the globally consumed tea plant. Stewartia gemmata, a species of the earliest diverging tribe Stewartieae, is critical to offer insights into Theaceae's origin and evolutionary history. Result: We sequenced the complete organelle genomes of Stewartia gemmata using short/long reads sequencing technologies. The chloroplast genome (158,406 bp) exhibited a quadripartite structure including the large single-copy region (LSC), a small single-copy region (SSC), and a pair of inverted repeat regions (IRs); 114 genes encoded 80 proteins, 30 tRNAs, and four rRNAs. The mitochondrial genome (681,203 bp) exhibited alternative conformations alongside a monocyclic structure: 61 genes encoding 38 proteins, 20 tRNAs, three rRNAs, and RNA editing-impacting genes, including ATP6, RPL16, COX2, NAD4L, NAD5, NAD7, and RPS1. Comparative analyses revealed frequent recombination events and apparent rRNA gene gains and losses in the mitochondrial genome of Theaceae. In organelle genomes, the protein-coding genes exhibited a strong A/U bias at codon endings; ENC-GC3 analysis implies selection-driven codon bias. Transposable elements might facilitate interorganelle sequence transfer. Phylogenetic analysis confirmed Stewartieae's early divergence within Theaceae, shedding light on organelle genome characteristics and evolution in Theaceae. Conclusions: We studied the detailed characterization of organelle genomes, including genome structure, composition, and repeated sequences, along with the identification of lateral gene transfer (LGT) events and complexities. The discovery of a large number of repetitive sequences and simple sequence repeats (SSRs) has led to new insights into molecular phylogenetic markers. Decoding the Stewartia gemmata organellar genome provides valuable genomic resources for further studies in tea plant phylogenomics and evolutionary biology.

Plant vacuolar-type Na⁺, K⁺/H⁺ antiporters (NHXs) play important roles in pH and K⁺ homeostasis and osmotic balance under normal physiological conditions. Under salt stress, vacuolar-type NHX enhances salt tolerance by compartmentalizing Na⁺ into vacuoles. However, the ion transport mechanism of vacuolar-type NHX remains poorly understood due to the absence of resolved protein crystal structures. To investigate the ion transport mechanism for vacuolar-type NHX, the three-dimensional structure of rice vacuolar-type NHX1 (OsNHX1) was established through homology modeling and AlphaFold3.0. The OsNHX1 model contains thirteen transmembrane segments according to hydrophobic characteristics and empirical and phylogenetic data. Furthermore, this study validated the OsNHX1 model via functional experiments, revealing a set of key charged amino acids essential for its activity. Mapping these amino acids onto the OsNHX1 model revealed that its pore domain exhibits a transmembrane charge-compensated pattern similar to that of NHE1 while also displaying a distinct charge distribution on either side of the pore domain. Comparative analysis of the key amino acid sites responsible for ion transport in the crystal structure of OsSOS1 and NHE1 revealed that OsNHX1 employs a unique ion transport mechanism. This study will enhance our understanding of the function and catalytic mechanism of OsNHX1 and other plant vacuolar-type NHXs.

Growing evidence links processed red meat consumption to increased diabetes risk, with oxidized proteins and/or amino acids proposed as potential mediators. We investigated whether dityrosine (Dityr), a key oxidation biomarker in high-oxidative pork (HOP) and structural analog of thyroid hormone T3, mediates HOP-induced glucose dysregulation via thyroid hormone (TH) signaling disruption. C57BL/6J mice were fed control, low-oxidative pork (LOP), HOP, LOP + Dityr, or Dityr diets for 12 weeks. HOP and Dityr impaired glucose tolerance and induced hyperglycemia and hypoinsulinemia. Both induced oxidative stress and inflammation that partly contributed to pancreatic β-cell dysfunction and reduction in insulin secretion. Crucially, they downregulated pancreatic thyroid hormone receptor β1 (TRβ1) and monocarboxylate transporter 8 (MCT-8), impairing TH signaling. This reduced TH transport in pancreatic tissue and triggered β-cell apoptosis by modulating TRβ1-mediated expression of TH-responsive genes and proteins involved in pancreatic function, ultimately leading to diminished insulin secretion and elevated blood glucose levels. Dityr alone recapitulated the metabolic and molecular disruptions of HOP. We conclude that Dityr drives HOP-induced glucose metabolism disorders primarily by disrupting TH signaling, along with promoting oxidative stress and inflammation that collectively impair β-cell function. Minimizing dietary Dityr exposure via modified cooking methods or antioxidant-rich diets may mitigate diabetes risk.

Bidens pilosa L., an annual herbaceous plant with a wide distribution, possesses novel medicinal properties. In January 2021, a powdery mildew disease outbreak was documented on B. pilosa plants located in the roadside areas in Shenzhen, Guangdong Province, China, with 60 to 80% disease incidence. Initial symptoms manifested as small, irregular white powdery patches, primarily on the adaxial surfaces of leaves. Subsequently, the colonies expanded, forming coalescent colonies that spread across the leaves, petioles, and stems, eventually leading to the distortion and senescence of leaves. Hyphae are hyaline, flexuous to straight, septate, with thin walls and a width ranging from 2 to 8 μm. Hyphal appressoria are nipple-shaped. Conidophores are erect or slightly flexuous, ranging from 80 to 150 µm in length and 12 to 18 µm in width (n = 30). Typically, these conidophores bear chains of 2 to 5 immature conidia, displaying a sinuate outline. Foot-cells, located at the base of conidophores, are cylindrical and erect, approximately 33 to 100 µm in length and 6 to 10 µm in width (n = 30). Conidia are hyaline, ellipsoid-ovoid to barrel-shaped, and lack fibrosin bodies. Primary conidia are ellipsoid-ovoid in shape, characterized by a rounded apex and a subtruncate base, 25 to 40 µm × 15 to 22 µm in width. Secondary conidia are barrel-shaped with truncate or subtruncate ends, 27 to 35 µm × 15 to 20 µm in width. Germ tubes exhibit a longitubus pattern and are prominently produced at the perihilar or apical region of the conidia. No chasmothecia were observed in the collected samples. In order to conduct a molecular-level identification, mycelium and conidia were collected from B. pilosa leaves. Genomic DNA was subsequently extracted from these samples. The internal transcribed spacer (ITS), intergenic spacer (IGS) and beta-tubulin (tub2) sequences were performed using primer pairs ITS1/ITS4, IGS-12a/NS1R, and tub2, respectively (Carbone and Kohn 1999; Scholin et al. 1994; White et al.,1990). A 568-bp ITS, a 366-bp IGS, and a 354-bp tub2 sequences (GenBank accession nos. OR647592, OR978282 and OR978283) were obtained. The ITS sequence exhibited over 99.6% similarity to Golovinomyces ambrosiae (MT929773) and G. cichoracearum (MH590731). The IGS sequence displayed 100% similarity to G. ambrosiae (MK383490) and G. ambrosiae (OK349420). The tub2 sequence displayed 100% similarity to G. ambrosiae (MW981257) and G. ambrosiae (MW981256). Phylogenetic analysis of IGS, ITS and tub2 also grouped obtained sequences within the G. ambrosiae complex. Based on the analysis of morphological characteristics and sequence identity, the pathogen was identified as G. ambrosiae. In order to satisfy Koch's postulates, an infected leaf was carefully pressed onto leaves of six healthy young B. pilosa plants, each grown in a separate pot. Additionally, a control group consisted of six non-inoculated plants. All plants were placed in a greenhouse: 25°C, 14/10-h light/dark photoperiod, and relative humidity 50%. After 10 days, the inoculated leaves exhibited powdery mildew colonies similar to those observed in the original infected plants. At 16 days, the inoculated leaves exhibited discoloration and premature leaf drop. The pathogenicity test was conducted twice. Microscopic observation and sequencing confirmed that isolated fungus was identical to the original pathogen. G. ambrosiae has previously been documented on B. pilosa in Fuzhou, Fujian Province, China (Mukhtar et al., 2022). However, to the best of our knowledge, this study represents the first report of powdery mildew caused by G. ambrosiae on B. pilosa in Shenzhen, Guangdong Province, China.

Camellia gauchowensis is widely distributed in South China. Field observations indicate that it produces abundant flowers but yields relatively few fruits under natural conditions. Understanding the intrinsic and extrinsic drivers of this low fruit output is essential both for revealing adaptive strategies in oil-tea camellia and informing cultivation improvement. In this study, we comprehensively investigated the flowering phenology, floral traits, pollen traits, pollinator activity, and breeding-system characteristics of C. gauchowensis. The results showed that C. gauchowensis produces perfect flowers but suffers from a narrow effective pollination window during its late-autumn-to-winter flowering period. Stomium-cell contaminants mixed with pollen grains may contribute to its poor pollen germination capacity. Cytochemical staining (TTC and FDA) significantly overestimated viability compared to in vitro germination results, and thus could not serve as a reliable substitute for functional pollen assessment. Both the outcrossing index and the pollen–ovule ratio indicated that C. gauchowensis exhibits a reproductive tendency toward outcrossing, with its sexual reproduction largely dependent on pollinators. Among the recorded floral visitors, Apis cerana represents the most promising pollinator candidate owing to its numerical dominance, frequent stigma contact, and superior cold-tolerance capacity. Our results reveal that reproductive success in C. gauchowensis is collectively constrained by multiple factors: a narrow effective pollination window, low pollen viability, winter-driven pollinator scarcity, and its reproductive tendency toward outcrossing. This study elucidates the coupled intrinsic–extrinsic mechanisms underlying low fruit output in this winter-flowering oil-tea camellia and provides theoretical underpinnings for pollination management and high-yield cultivation of this economically important woody crop.