Chuanjin Yu

Polyendocrine metabolic ovarian syndrome (PMOS) features intertwined reproductive, endocrine and metabolic defects, yet its initiating mechanisms remain incompletely understood. Here we show that an epigenetic mechanism driven by nicotinamide N-methyltransferase (NNMT) in granulosa cells contributes to disease progression in PMOS. We observe that Nnmt overexpression in mouse granulosa cells reduces histone H3 lysine 27 trimethylation (H3K27me3), leading to increased retinoic acid receptor beta (RARB) expression. RARB, in turn, amplifies ovarian androgen synthesis. The resulting androgen excess further suppresses H3K27me3, locking cells into a feedforward loop that sustains hyperandrogenism and disrupts follicle development. Pharmacological inhibition of NNMT restores H3K27me3, disrupts the RARB–androgen feedback circuit, and ameliorates both metabolic and hormonal phenotypes in PMOS models. Our findings suggest NNMT as a regulator of PMOS through metabolic and epigenetic reprogramming. The NNMT–H3K27me3–RARB–androgen axis emerges as a mechanistic nexus linking methionine and epigenetic dysregulation to PMOS pathogenesis and represents a tractable therapeutic target.

: Polycystic ovary syndrome (PCOS) is a frequent endocrine and metabolic imbalance that typically occurs in women of reproductive age. Its molecular pathophysiology is yet unknown, especially the ovarian cellular metabolic inefficiency that causes the transcriptional dysregulation of key genes linked to PCOS. Here, we discovered that one transcriptional-like regulator that causes PCOS is nuclear pyruvate kinase M2 (nPKM2). Using multiomics techniques, we show that enhanced lactylation of histone 3 on lysine residues 9 and 18 is linked to nPKM2 binding to the genome, changing the three-dimensional architecture of the genome. Genomic compartment switching, topologically associated domain fusion, and novel enhancer–promoter interactions subsequently enhance the expression of PCOS-related genes, including CYP17A1 and CYP11A1 . In mice, ectopic expression of Pkm2 in female GCs consistently presented PCOS-like traits, such as interrupted estrous cycles, hyperandrogenism, and so on. Importantly, whole-organ tracing imaging directly unfolded the number of small follicles, which increased highly in Pkm2 -tdtomato transgene mice compared with control. Furthermore, pharmacological inhibition of the nuclear accumulation of PKM2 mitigated PCOS-like symptoms in mice and restored a wild-type-like transcriptome. This study demonstrates the important function of PKM2-mediated histone lactylation in regulating the three-dimensional chromatin architecture and highlights PKM2 as a potential therapeutic target for PCOS treatment.

Polycystic ovary syndrome is the primary cause of female infertility. Growing evidence suggests that dysregulation of amino acid metabolism plays a significant role in the onset and progression. However, the underlying mechanism remains unclear. In this study, we conduct targeted metabolite profiling of human follicular fluid and granulosa cells. A significant increase in glutamine uptake is observed in patients with hyperandrogenic polycystic ovary syndrome, mediated by the upregulation of SLC1A5, a specific glutamine transporter. We find that androgen excess primarily activates SLC1A5 expression. Furthermore, SLC1A5 overexpression in female mice induces polycystic ovary syndrome-like phenotypes, including hyperandrogenism and abnormal follicle development. Additionally, the pharmacological blockade of SLC1A5 provides reproductive benefits to mice exhibiting polycystic ovary syndrome-like symptoms. Mechanistically, we show that elevated flux of Gln-derived α-ketoglutarate enhances HDAC5 expression and suppresses acetylation on histone 3 lysine residue 14 and lysine residue 56. The reduction in acetylation level is associated with the downregulation of several genes related to folliculogenesis, including CYP19A1, thereby exacerbating androgenic homeostasis imbalance. These findings indicate that androgen-induced aberrant glutamine uptake via SLC1A5 is crucial for the development and progression of polycystic ovary syndrome, suggesting pharmacological blockade of SLC1A5 as a potential therapeutic strategy.

As the rapid-changing in Trichoderma taxonomy, an efficient identification of Trichoderma species is an urgent issue for Trichoderma -based research. In this study, based on the current taxonomy of Trichoderma , we constructed curated databases including 338 ITS sequences, 435 TEF1 sequences, 415 RPB2 sequences and 28 phenotypic characters. In addition, a polyphasic identification system (PIST) was developed. Within PIST, the resolution ability of molecular and phenotype characters could be combined for species identification in a step-by-step way. Compared with other identification systems, the involved Trichoderma species were extended from 88 to 252 species and 175 from 188 tested Trichoderma species could be identified within PIST. In most tested cases, three nucleotide markers and phenotypic characters showed improved identification performance. The TEF1 sequences have superior resolution than other characters. Importance: The genus Trichoderma is important to human society with a wide application in industry, agriculture and environment bio-remediation. Thus, a quick and accurate identification of Trichoderma spp. is paramount since it is usually the first step to conduct a Trichoderma -based scientific research and is an obstruction especially for those researchers as nematologist, chemists, nutritionist and the like, lacking of taxonomic knowledge of fungi.

Trichoderma atroviride SG3403 showed high biocontrol activity against southern corn leaf blight (SCLB; pathogen: Cochliobolus heterostrophus). T. atroviride SG3403 could cause death of C. heterostrophus race O hypha on plates. Spraying T. atroviride SG3403 conidia suspension over maize seedling leaves protected the corn from SCLB infection. Biocontrol effect lasted for 30 days in the field. Trichoderma strain was able to induce resistance response in corn leaves against pathogen infection. In corn leaves treated with T. atroviride SG3403, the enzyme activities of phenylalanine ammonia lyase (PAL) and superoxide dismutase (SOD) reached the highest at 24 h, enzyme activity of catalase (CAT) reached the highest at 36 h after inoculation of pathogen C. heterostrophus race O. RNA expression levels of Pal, Sod and Cat (which synthesis enzyme PAL, SOD and CAT) were also upregulated and corresponded to the enzyme activity at the same time point. Enzyme activities and corresponding genes expression induced by Trichoderma SG3403 was more obvious than that induced by pathogen only, which implies that T. atroviride SG3403 induced corn defense gene expression against pathogen infection. Thus, induced resistance mechanism was possibly involved in the biocontrol of SCLB by T. atroviride SG3403.

The tolerance to organophosphate pesticide, dichlorvos, is essential for the application of Trichoderma in bioremediation and integrated pest management, although the molecular events associated with the tolerance process have not yet been elucidated. RNA-seq analysis of wild-type Trichoderma atroviride T23 and the hex1-deleted mutant under dichlorvos stress was designed to search for genes involved in the tolerance process. A total of 5382 differentially expressed genes were identified, highlighting the complex transcriptional changes of T. atroviride in response to dichlorvos stress. 137 genes were regulated by dichlorvos and hex1, encoding major facilitator superfamilies, cytochrome P450, glutathione-S-transferase, flavoprotein, Hsp70, Hsp90, etc. Pathway and expression analysis indicated that ABC transporters were affected by the disruption of hex1 gene and might play a vital role in the tolerance process. Expression patterns of seven selected ABC transporter genes were confirmed by qRT-PCR after exposure to dichlorvos for 2, 6 and 24 h. The present study provides insights into the genetic basis of dichlorvos tolerance in Trichoderma that may be exploited for further development of bioremediation or biocontrol agents.