Lactylation of CREB is required for FSH-induced proliferation and differentiation of ovarian granulosa cells.

Follicle-stimulating hormone (FSH) promotes follicular development by inducing the proliferation and differentiation of granulosa cells (GCs). This process is primarily attributed to the activation of the canonical G protein-coupled receptor (GPCR)/adenylyl cyclase/cAMP/PKA/CREB signaling pathway. Here, we revealed a novel mechanism wherein FSH promotes GCs proliferation and differentiation by stimulating cAMP response element-binding protein (CREB) lactylation. Specifically, FSH induced CREB lactylation at lysine 136 (K136la), leading to CREB phosphorylation at serine 133, which facilitated CREB/CBP/P300 complex formation for transcription activation. Moreover, K136la alone directly recruited CBP/P300, triggering transcriptional surges of proliferation and differentiation genes by binding with the cAMP response element (CRE), thereby stimulating GCs proliferation and differentiation. By contrast, a CREB mutation at K136 eliminated these effects. Blocking CREB lactylation using oxamate or C646 in vivo suppressed GCs proliferation, differentiation, and follicular development in mouse ovaries. These findings highlight the important role of lactylation between metabolic regulation and folliculogenesis, and its importance in mediating GPCR signaling, providing a theoretical basis for treating female infertility associated with defective follicular development.