FSHR (follicle-stimulating hormone receptor) is a G protein-coupled receptor that binds follicle-stimulating hormone (FSH) and plays crucial roles in reproductive and metabolic processes 123. Upon FSH binding, FSHR primarily activates GΞ±s protein, leading to increased cAMP production and activation of downstream PI3K-AKT and ERK1/ERK2 signaling pathways 2. The receptor undergoes oligomerization and can form heterodimers with other GPCRs, enabling trans-activation and biased signaling 4. In reproductive tissues, FSHR is essential for spermatogenesis in males and folliculogenesis in females, with complete FSHR loss causing follicular development blockade at the primary stage 5. Core fucosylation by FUT8 is critical for FSHR function, as it enhances FSH-FSHR binding and downstream signaling 6. Beyond reproduction, FSHR is expressed in pancreatic Ξ²-cells where FSH regulates glucose-stimulated insulin secretion in a bell-curve manner through cAMP/PKA and calcium pathways 7. Clinically, FSHR polymorphisms are associated with male infertility risk, particularly combined genotypes showing increased susceptibility 89. The FSHR/GPER expression ratio serves as a biomarker distinguishing mature from immature follicles in assisted reproduction 10. Disease associations include ovarian dysgenesis and ovarian hyperstimulation syndrome.