# METTL3 regulates Leydig cell proliferation via miR-145-PCK1 mediated gluconeogenesis in goats

## TL;DR

This study reveals how METTL3 regulates Leydig cell proliferation in goats through a pathway involving miR-145 and PCK1, impacting testicular development and male fertility.

## Contribution

The study identifies a novel METTL3/miR-145-3p/PCK1 regulatory axis linking epigenetic modification to metabolic activity in Leydig cells.

## Key findings

- METTL3 downregulation reduces miR-145-3p levels by decreasing m6A modification on pri-miR-145.
- Reduced miR-145-3p increases PCK1 expression, activating gluconeogenesis and promoting Leydig cell proliferation.
- This metabolic shift upregulates cyclin B1 and cyclin E2, supporting testicular growth in goats.

## Abstract

Normal testicular development is essential for maintaining male fertility and reproductive performance in livestock. Leydig cells (LCs) play a central role in testicular physiology; however, the epigenetic mechanisms regulating their development remain largely unclear. Methyltransferase-like 3 (METTL3), a key m6A methylation enzyme, and microRNAs are increasingly recognised as critical regulators of this process.

METTL3 expression in goat LCs markedly decreased during testicular development. This downregulation reduced m6A modification on pri-miR-145, impairing DiGeorge syndrome critical region 8-mediated processing and resulting in decreased levels of mature miR-145-3p. This reduction in miR-145-3p increased the expression of phosphoenolpyruvate carboxykinase 1 (PCK1), which activated gluconeogenesis, increased intracellular glucose levels, and increased mitochondrial membrane potential. Consequently, this metabolic shift upregulated cell cycle-related genes (cyclin B1 and cyclin E2), promoting LC proliferation and testicular growth.

Our findings demonstrate that the METTL3/miR-145-3p/PCK1 axis is a key regulatory pathway linking epigenetic modification to the metabolic activity and proliferation of LCs. This mechanism provides novel insights into the molecular control of testicular development in male goats and may offer new targets for improving male reproductive capacity in livestock.

The online version contains supplementary material available at 10.1186/s40104-025-01307-5.