Biology

Perfluorooctane sulfonate (PFOS) has been widely utilized in products such as cotton textiles, hydraulic oils, coatings, pharmaceuticals, cosmetics, etc. Now it is widely distributed in various environmental media, wildlife, and human bodies. Polystyrene (PS) as a kind of plastics, their products under the physical, chemical, and biological decomposition in the environment are widely distributed in the air, soil, oceans, surface water, and sediments. However, PS and PFOS often coexist in the environment, making the study of their combined exposure mechanisms more aligned with actual conditions. This research integrates network toxicology and molecular biology techniques to predict the toxicity and common differentially expressed gene enrichment pathways of PFOS and PS. This study investigates the toxic effects of combined exposure to PFOS and PS on the mouse growth and development, immune functions, and other aspects. Additionally, it delves into the expression differences in various genes in mice after stimulation by PFOS and PS, the pathological changes in multiple organs, and the toxic effects on organs such as the liver, kidneys, and intestines. The results reveal that combined exposure to PFOS and PS does not significantly damage the kidney but leads to morphological damage in the liver and intestinal tissues, reduced antioxidant capacity, and the occurrence of inflammation. Based on the network toxicology findings, it is hypothesized that during combined exposure to PFOS and PS, the exacerbation of inflammatory responses further mediates the reduction in antioxidant capacity and the intensification of oxidative stress, ultimately resulting in tissue damage. This study provides innovative theoretical and research directions for the detection and prevention of combined exposure to PFOS and PS, offering a new paradigm for toxicological research, with significant theoretical and practical implications.

The biosynthesis of AAAs in plants primarily relies on the shikimate pathway, with metabolic flux sustained by NADPH and E4P generated via the OPP pathway. However, how OPP enzymes coordinate to support AAA production remains unclear. Here, we investigated the direct interaction between two consecutive NADPH-producing enzymes, G6PD6 and PGD2, and its role in metabolic coupling. Using BiFC, Co-IP, pull-down assays, and domain mapping, we showed that G6PD6 and PGD2 form a cytosolic protein complex via the C-terminal domain of PGD2. Structural modeling identified potential interaction residues: PHE²⁹⁴, GLY²⁹⁷, and LEU²⁹⁸ in PGD2, and GLY³⁵¹, LYS⁴⁹⁹, and ALA⁵⁰⁰ in G6PD6. Overexpression of either enzyme partially rescued the dwarf phenotype of adh2 mutants caused by AAA deficiency. These findings indicate that the PGD2–G6PD6 complex coordinates OPP-derived reductive power and carbon flux to support downstream AAA biosynthesis. This study reveals a functional link between OPP enzyme interactions and AAA production, suggesting that metabolic flux can be regulated through direct enzyme–enzyme association. Future work will explore how this complex responds to metabolic demand and whether additional components contribute to coordinating flux between the OPP and shikimate pathways.

Sophora moorcroftiana is a perennial deciduous dwarf shrub that exhibits remarkable ecological adaptability, including strong drought resistance on the Tibetan Plateau. In this study, the complete mitogenome of S. moorcroftiana was reported and assembled for the first time, representing a circular molecule of 534,205 bp with a GC content of 44.93%. The mitogenome was annotated to include 33 unique protein-coding genes (PCGs), 19 tRNA genes, and three rRNA genes. Phylogenetic and collinearity analyses of the mitogenomes of S. moorcroftiana and related species revealed their evolutionary relationships and a non-conserved structure. The codon usage of the PCGs and 166 simple sequence repeats was also analyzed. Conjoint analysis of the transcriptome and mitogenome identified 587 RNA editing sites across 33 PCGs, with 14 genes significantly induced in the roots under drought treatment. Moreover, the levels of proline, soluble sugar, soluble protein, and peroxidase activity were significantly elevated in S. moorcroftiana roots subjected to different PEG6000 concentrations. These findings provide valuable insights into the molecular mechanisms underlying drought responses and offer genetic resources for improving drought resistance in S. moorcroftiana.

Skeletal muscle is the largest organ system in mammals. To investigate the differences in energy metabolism across various skeletal muscles in Yili horses, this study examined muscle fiber type distributions through immunohistochemical staining of muscles, including the splenius, triceps brachii, longissimus dorsi, and gluteus medius. The splenius and gluteus medius muscles, which exhibited the greatest differences in the proportion of slow-twitch fiber area, were selected for further comparison of differential metabolites and transcriptomic expression profiles between slow-twitch and fast-twitch fibers. A total of 27 energy metabolism-related differential metabolites, including pyruvate and lactate, were identified, along with 432 differentially expressed genes, such as PFKM and ALDOA. Additionally, 164 differentially expressed miRNAs, including miR-499 and miR-24-3p, were detected. We found highlighted differences in LDHA expression between the gluteus medius and splenius muscles, which may influence the conversion of fast and slow muscle fibers by modulating the glycolysis/gluconeogenesis pathway. The miRNA−mRNA targeting relationships established here warrant further validation. These findings provide valuable insights into the molecular mechanisms underlying energy metabolism differences in Yili horses.