Fig. 3From: Follicle-stimulating hormone signaling in Sertoli cells: a licence to the early stages of spermatogenesisFunctions of FSH signaling in early stages of spermatogenesis. Activating cAMP/PKA signaling pathway induces expression of GDNF and FGF2 in SC which will be secreted to SSC to maintain spermatogonia pool. Notably, FSH can inhibit degradation of GDNF via suppressing lysosomal biogenesis. This process is validated by activating PI3K/Akt/mTOR pathway. Additionally, FSH negatively regulates PGE2 through inhibiting AMH. PGE2 is also important for spermatogonia pool maintenance. SLF, SCF, Igf3 and BMP4 that is activated via cAMP/PKA pathway, along with transferrin through unknown pathway, contribute to spermatogonia differentiation. FSH ensures entry into meiosis through regulating DNA synthesis and chromosome dynamics. FSH regulates DNA synthesis via temporally inhibiting IL-6, Activin A and inducing Inhibin B. Chromosome dynamics is positively regulated by nociception via cAMP/PKA signaling pathway. Also, FSH upregulates Nrg1 and Nrg3 to induce Stra8 expression in spermatocytes. Besides, limiting gem cell apoptosis by inhibiting Gal3 and Bok is another task of FSH signaling in SCs. Dotted line represents unknown mechanismBack to article page