Forkhead box O member FOXO1 regulates the majority of follicle-stimulating hormone responsive genes in ovarian granulosa cells

Abstract

FSH promotes maturation of ovarian follicles. One pathway activated by FSH in granulosa cells (GCs) is phosphatidylinositol-3 kinase/AKT. The AKT target FOXO1 is reported to function primarily as a repressor of FSH genes, including Ccnd2 and Inha. Based on its broad functions in other tissues, we hypothesized that FOXO1 may regulate many more GC genes. We transduced GCs with empty adenovirus or constitutively active FOXO1 followed by treatment with FSH for 24 hours, and conducted RNA deep sequencing. Results show that FSH regulates 3,772 genes ≥ 2.0-fold; 60% of these genes are activated or repressed by FOXO1. Pathway Studio Analysis revealed enrichment of genes repressed by FOXO1 in metabolism, signaling, transport, development, and activated by FOXO1 in signaling, cytoskeletal functions, and apoptosis. Gene regulation was verified by q-PCR (eight genes) and ChIP analysis (two genes). We conclude that FOXO1 regulates the majority of FSH target genes in GCs.

FSH for the Treatment of Male Infertility

“…By these means, FOXO1 can no longer stimulate the expression of autophagy-related genes [35]. FOXO1 is key to the differentiating action of FSH, at least in granulosa cells and, quite unexpectedly, a recent genome-wide analysis revealed that most FSH-responsive genes had FOXO1-binding sites in their promoter (60% of identified genes), and not CREB-binding elements (CRE), as anticipated [36]. While FOXO1 is constitutively nuclear and bound to DNA, where, for example, it inhibits the expression of proliferation genes such as Cyclin D2 [37], these data suggest that the role of FSH would be to counteract the general action of this transcription factor.…”

Follicle-Stimulating Hormone (FSH)-dependent Regulation of Extracellular Regulated Kinase (ERK) Phosphorylation by the Mitogen-activated Protein (MAP) Kinase Phosphatase MKP3

“…Indeed, in a recent report, DUSP27 blocked ERK but not MEK phosphorylation in a rat luteal cell line in response to prolactin treatment (40). However, DUSP27 is not expressed in rat GCs based on both microarray (41) and RNA sequencing (22) results. Although 61 DUSPs have been identified (as reviewed in Ref.…”

“…The tyrosine phosphatase SRC homology 2 domain-containing tyrosine phosphatase (SHP2) is also required for RTK signaling into MEK/ ERK and is generally believed to contribute to the activation of RAS (26 -28). We determined whether SHP2 activity was required for the phosphorylation of MEK(Ser 217 /Ser 221 ) by pretreating GCs without or with NSC 87877, a compound that selectively inhibits SHP1 (which is not expressed in rat GCs based on RNA sequencing results (22)) and SHP2 (29 . A, GCs were treated for 15 min without (DMSO) or with 250 nM AG1478, an EGFR kinase inhibitor, followed by treatment without (veh) or with 50 ng/ml FSH for 15 min.…”

“…Although 61 DUSPs have been identified (as reviewed in Ref. 42), preantral GCs only express DUSPs 1, 3,6,7,10,11,12,16,18,19, and 22 as well as cell division cycle (CDC) dual specificity phosphatase CDC25A, 25B, and 25C mRNAs based on RNA sequencing results (22). Only a subgroup of the DUSPs are classified as MKPs based on the presence of a CDC25-like domain that confers specificity toward A, GCs were pretreated without (EtOH) or with 0.2 M okadaic acid, a PP2 inhibitor, for 1 h, followed by treatment without (veh) and with FSH for 15 min.…”

The Ovarian Transcriptome of Reproductively Aged Multiparous Mice: Candidate Genes for Ovarian Cancer Protection

“…The forkhead box (FOXO) family of transcription factors is implicated in longevity and aging-related processes, including cell cycle arrest, oxidative stress, DNA repair, apoptosis, and autophagy [47]. Foxo1 is a master regulator of FSH-target genes in granulosa cells [48]. It is highly expressed in growing follicles, repressed during luteinization, and induced in atretic and developing cystic follicles of middle-age acyclic rats at persistent estrous [49].…”