TRIM28-dependent SUMOylation protects the adult ovary from activation of the testicular pathway

Abstract

Gonadal sexual fate in mammals is determined during embryonic development and must be actively maintained in adulthood. In the mouse ovary, oestrogen receptors and FOXL2 protect ovarian granulosa cells from transdifferentiation into Sertoli cells, their testicular counterpart. However, the mechanism underlying their protective effect is unknown. Here, we show that TRIM28 is required to prevent female-to-male sex reversal of the mouse ovary after birth. We found that upon loss of Trim28, ovarian granulosa cells transdifferentiate to Sertoli cells through an intermediate cell type, different from gonadal embryonic progenitors. TRIM28 is recruited on chromatin in the proximity of FOXL2 to maintain the ovarian pathway and to repress testicular-specific genes. The role of TRIM28 in ovarian maintenance depends on its E3-SUMO ligase activity that regulates the sex-specific SUMOylation profile of ovarian-specific genes. Our study identifies TRIM28 as a key factor in protecting the adult ovary from the testicular pathway.

FOXL2 interaction with different binding partners regulates the dynamics of ovarian development

“…This study demonstrated the plasticity of the adult ovary and the crucial role played by FOXL2 in this process. More recently, a similar role in ovarian sex maintenance was discovered for TRIM28, which we show to be recruited on chromatin together with FOXL2 and to regulate the sex-specific SUMOylation profile of ovarian-specific genes through its E3-SUMO ligase activity [8].…”

“…We then scanned the 1 Mb gene desert upstream of Sox9, which was previously found to contain cis-regulatory elements essential for Sox9 expression in Sertoli cells [38,39]. As previously shown [8,27], neither TESCO nor enhancer 13, were significantly bound by FOXL2 at any point during ovarian development. Instead, we observed a dynamic binding of FOXL2 in other known Sox9 enhancers.…”

“…Ovarian development was considered as a default pathway activated in the absence of Sry [7]. Recent work has challenged this idea showing that female sex determination is not a default pathway, but an active process involving the constant repression of the genetic program of the opposite sex [8][9][10]. A critical player in ovarian development and function is Foxl2, a gene encoding for the forkhead box L2 (FOXL2) protein, a transcription factor involved in regulating the differentiation and maintenance of granulosa cells in the ovary [11,12].…”

Loss of SUMO-specific protease 2 causes isolated glucocorticoid deficiency by blocking adrenal cortex zonal transdifferentiation in mice

“…SUMOylation has already proven a role in adrenocortical development with the unSUMOylatable SF-1 2KR/2KR model, which results in adrenal cells expressing gonadal markers 21 . In ovaries which share a common foetal origin with adrenals, SUMOylation by the E3 SUMO-ligase activity of TRIM28, is essential for maintenance of granulosa cell fate at the expense of Sertoli-like identity 58 , whereas SENP1 presence in stromal cells is necessary for proper oocyte maturation and ovulation 59 . From a broader perspective, our study belongs to a growing corpus of evidence associating SUMOylation with coordination of differentiation in different tissues and cell types such as white and brown adipose tissue 15 , 17 , 60 , induced pluripotent stem cells 16 , or intestine 18 .…”

Cocktails of NSAIDs and 17α Ethinylestradiol at Environmentally Relevant Doses in Drinking Water Alter Puberty Onset in Mice Intergenerationally

“…For IF analysis, tissue sections were deparaffinized, followed by antigen retrieval with 10 mM citrate buffer (pH 6) in the Histo5 apparatus (Milestone, Brondby, Denmark) for 20 min, as previously described [ 127 , 148 ]. Sections were then blocked with 10% donkey serum (Sigma-Aldrich) or 1/1000 anti-goat IgG (Thermofisher, Waltham, MA, USA), and incubated (4 °C, overnight) with the following primary antibodies: monoclonal mouse anti-PCNA (Sigma-Aldrich P8825, 1/500), anti-phospho-gH2Ax (Ser139 clone JBW301, Sigma Aldrich 05-636, 1/500), anti-COUPTFII (RD systems PP-H7147-00, 1/400), a-tubulin (Sigma Aldrich T9026, 1/1000), monoclonal rat anti-phosphorylated-Histone H3 (Ser10, Sigma Aldrich H9908, 1/400), anti-Tra98 (Abcam ab82527, 1/400), polyclonal guinea pig anti-PADI6 (1/500), polyclonal goat anti-Sox9 (RD systems AF3075, 1/300), polyclonal rabbit anti-FoxL2 (homemade [ 149 ], 1/300), anti-AMH (gift from N DiClemente, 1/300), anti-Lin28a (ProteinTech 11724, 1/400), anti-connexin-43 (Sigma Aldrich C6219, 1/500), and anti-a Smooth muscle actin (SMA) (Abcam ab124964, 1/500). Sections were then incubated with donkey or goat secondary antibodies conjugated with Alexa Fluor 555, 488, or 649 (Thermofisher, 1/1000) at room temperature for 30 min, followed by Hoechst staining.…”