The formins inhibitor SMIFH2 inhibits the cytoskeleton dynamics and mitochondrial function during goat oocyte maturation.

The cytoskeleton plays a crucial role in facilitating the successful completion of the meiotic maturation of oocytes. Its influence extends to the process of oocyte nuclear maturation and the proper functioning of various organelles during cytoplasmic maturation. The formin family of proteins plays a crucial role in the molecular regulation of cytoskeletal assembly and organization; however, its role in goat oocytes are not fully understood. Our study examined the inhibition of formins activity, which revealed its crucial role in the maturation of goat oocytes. We observed that the inhibition of formins resulted in meiotic defects in goat oocytes, as evidenced by the hindered extrusion of polar bodies and the expansion of cumulus cells. Additionally, the oocytes exhibited altered actin dynamics and compromised spindle/chromosome structure upon formins inhibition. The results of the transcriptomic analysis highlighted a noteworthy alteration in the mRNA levels of genes implicated in mitochondrial functions and oxidative phosphorylation in formins inhibited oocytes. Validation experiments provided evidence that the meiotic defects observed in these oocytes were due to the excessive early apoptosis induced by reactive oxygen species (ROS). Our findings demonstrate that the involvement of formins in sustaining the cytoskeletal dynamics and mitochondrial function is crucial for the successful meiotic maturation of goat oocytes.