Down-regulation of miR-138-5p in PP2A KO mice promoted apoptosis of spermatocytes.

Background: Protein phosphatase 2 A (PP2A) is known to have a pivotal and diverse functions in various physiological processes. In the previous study, we utilized the cre-loxp system to generate germ cell-specific knockout mice for the PP2A catalytic subunit alpha subunit (Ppp2ca).

Methods And Results: Using high-throughput miRNA sequencing of testis tissues and real‑time PCR, we have identified a notable decrease in the expression of miR-138-5p in the testes of Ppp2ca mice. Our findings indicate that miR-138-5p plays a role in the regulation of apoptosis and proliferation of GC2 cells. Furthermore, bioinformatics analyses suggested that miR-138- 5p may target the transcriptional repressor Trps1. Consistent with these predictions, we observed a significant upregulation of Trps1 in the testes of Ppp2ca mice. Through transfection experiments, we have validated the negative regulation of Trps1 expression by miR-138-5p in GC2 cells.

Conclusion: Our study indicates that the down-regulation of miR-138-5p in PP2A KO mice, which targets Trps1 to promote spermatocyte apoptosis.