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Qi Su

Publications and source records attributed to Qi Su.

3 recordsLinked to original sources

Faecalibacterium prausnitzii-derived L-arginine ameliorates insomnia by inhibiting POMC-ACTH-cortisol axis.

Insomnia is associated with gut microbial dysbiosis, but the specific microbial metabolites mediating gut-brain communication remain elusive. Here, we integrate metagenomic sequencing from 171 individuals (primary insomnia, post-COVID insomnia, and controls) with functional pathway analysis and preclinical validation. We identify Faecalibacterium prausnitzii depletion and reduced L-arginine biosynthesis as consistent features in both insomnia subtypes, accompanied by elevated cortisol levels. Genomic and in vitro analyses confirm that F. prausnitzii is a key microbial contributor to L-arginine production. In a chronic mild stress mouse model, administration of either F. prausnitzii or L-arginine restores sleep duration, normalizes corticosterone levels, and reverses stress-induced gut dysbiosis. Mechanistically, L-arginine suppresses POMC gene expression and dampens adrenocorticotropic hormone (ACTH)-stimulated corticosterone release, implicating the POMC-ACTH-cortisol axis as a key target. These findings uncover a gut-brain axis driven by F. prausnitzii-derived L-arginine that modulates sleep through endocrine signaling, positioning this metabolite as a potential therapeutic avenue for insomnia.

Arginine

Coordinated regulation of glutathione S-transferases confers metabolic flexibility in multi-insecticide-resistant Frankliniella occidentalis (Pergande).

INTRODUCTION: The evolution of multi-insecticide resistance in insect pests threatens global food security. Although glutathione S-transferases (GSTs) are implicated in detoxification, the coordinated mechanism by which specific gene subfamilies interact to confer broad-spectrum resistance remains inadequately characterized. OBJECTIVE: To dissect the functional allocation and cooperation of GST subfamilies in multi-insecticide-resistant strains of Frankliniella occidentalis. METHODS: We integrated comparative genomics (20 GST genes cloned), transcriptomics (qRT-PCR), RNAi-mediated silencing, molecular docking (AutoDock Vina), and in vitro metabolism assays (UPLC-MS/MS) across susceptible and resistant thrips strains. RESULTS: The two resistant strains (NIL-R and FS-R) exhibited moderate to high resistance to five insecticides (chlorfenapyr, emamectin benzoate, spinetoram, spinosad, and thiamethoxam), accompanied by significantly elevated GSTs activity. Phylogenetic analysis indicates that GSTs include 10 conserved delta and 7 diverse sigma members. The sigma subfamily has undergone a marked expansion due to gene duplication. Delta (FoGSTd1, d4, and d9) and sigma (FoGSTs1, s2, and s6) genes were significantly up-regulated in the resistant strains. RNAi showed specialized functional allocation among GSTs: delta GSTs mediated resistance to spinosad and chlorfenapyr, sigma GSTs were responsible for thiamethoxam resistance, and notably, cooperation between these subfamilies contributed to resistance against emamectin benzoate and spinetoram. Molecular docking and in vitro metabolism assays of FoGSTd9 and FoGSTs1 proteins further supported the functional allocation and cooperative roles of GST subfamilies. CONCLUSION: Our results indicate that F. occidentalis may coordinate GST subfamilies to achieve metabolic flexibility in response to multi-insecticide pressure. This survival strategy, mediated by mechanistic functional allocation and cooperative interactions among subfamilies, may contribute to energy conservation and reduced adaptive costs. Disruption of this coordinated mechanism represents a potential approach for overcoming resistance in agricultural pest populations.

Animals

Misregulation of bromotyrosine compromises fertility in male Drosophila.

Biological regulation often depends on reversible reactions such as phosphorylation, acylation, methylation, and glycosylation, but rarely halogenation. A notable exception is the iodination and deiodination of thyroid hormones. Here, we report detection of bromotyrosine and its subsequent debromination during Drosophila spermatogenesis. Bromotyrosine is not evident when Drosophila express a native flavin-dependent dehalogenase that is homologous to the enzyme responsible for iodide salvage from iodotyrosine in mammals. Deletion or suppression of the dehalogenase-encoding condet (cdt) gene in Drosophila allows bromotyrosine to accumulate with no detectable chloro- or iodotyrosine. The presence of bromotyrosine in the cdt mutant males disrupts sperm individualization and results in decreased fertility. Transgenic expression of the cdt gene in late-staged germ cells rescues this defect and enhances tolerance of male flies to bromotyrosine. These results are consistent with reversible halogenation affecting Drosophila spermatogenesis in a process that had previously eluded metabolomic, proteomic, and genomic analyses.

Animals