Age-associated Mir-30E-3p Upregulation Drives Ovarian Follicular Granulosa Cell Senescence by Targeting DPY30 in Laying Hens

Ovarian aging in laying hens contributes significantly to the decline in egg production performance during the late laying period, and is accompanied by extensive remodeling of miRNA-mRNA interaction networks, which are critical post-transcriptional regulators during this process. In this study, we investigated the role of miR-30e-3p, which was previously identified as significantly upregulated during ovarian aging in laying hens, in granulosa cell (GC) senescence. To identify its downstream effectors, we performed mRNA transcriptome sequencing and screened for downregulated genes. Among potential targets, the histone methyltransferase complex regulatory subunit dpy-30 (DPY30) was validated as a direct target of miR-30e-3p by luciferase reporter and expression analyses. Functional assays demonstrated that miR-30e-3p significantly suppressed GC proliferation and induced cell cycle arrest, whereas DPY30 exhibited opposite effects. Furthermore, inhibition of miR-30e-3p or overexpression of DPY30 attenuated D-galactose (D-gal) -induced GC senescence. Mechanistically, miR-30e-3p promoted cellular senescence at least in part through downregulation of DPY30. Collectively, our findings indicated that miR-30e-3p promotes GC senescence by targeting DPY30 in chicken ovarian follicles, and suggest that both miR-30e-3p and DPY30 may serve as potential biomarkers for improving reproductive longevity and mitigating ovarian aging-related disorders in poultry.