Decreased LONP1 expression contributes to DNA damage and meiotic defects in oocytes.

Meiotic defects in oocytes are the primary reason for decreased female fertility with advanced maternal age. In this study, we revealed that decreased expression of ATP-dependent Lon peptidase 1 (LONP1) in aged oocytes and oocyte-specific depletion of LONP1 disrupt oocyte meiotic progression accompanying with mitochondrial dysfunction. In addition, LONP1 downregulation increased oocyte DNA damage. Moreover, we demonstrated that splicing factor proline and glutamine rich directly interacts with LONP1 and mediate the effect of LONP1 depletion on meiotic progression in oocytes. In summary, our data suggest that decreased expression of LONP1 is involved in advanced maternal age-related meiosis defects and that LONP1 represents a new therapeutic target to improve aged oocyte quality.