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Jiang, R.-F.

Publications and source records attributed to Jiang, R.-F..

4 recordsLinked to original sources

Superficial stromal cell population in the mouse uterus require METTL14 for development and functional competence to support embryo implantation

Uterine stromal cells are critical for pregnancy, coordinating embryo implantation, placental development, and maintenance of gestation. Single-cell RNA-seq analyses have identified two distinct stromal cell populations in the mouse uterus: superficial and deep stromal cells. However, their functional specialization remains unresolved. Here, we show that mice lacking methyltransferase-like 14 (METTL14), a core enzyme of the m6A methyltransferase complex, exhibit a selective depletion of superficial stromal cells while preserving deep stromal cells. This genetic model allowed us to investigate the physiological role of superficial stromal cells in uterine function. Paralleled by the aberrant development and loss of superficial stromal cells, Mettl14 deletion impaired embryo implantation and decidualization. Transcriptomic profiling revealed that Mettl14 deficiency disrupts hormonal signaling by upregulating estrogen (E2)-responsive genes and downregulating progesterone (P4)-responsive genes, resulting in aberrant development and loss of superficial stromal cells. Mechanistically, Mettl14 ablation reduces m6A methylation in the 3'-UTR of Esr1 mRNA, thereby impairing m6A-dependent mRNA degradation and elevating ESR1 expression, which amplifies E2 signaling. This study underscores the essential role of METTL14 in maintaining the superficial stromal cell population required for embryo implantation by regulating Esr1 mRNA stability through m6A modification.

physiology↗

Programmed downregulation of METTL3 is essential for decidualization in both humans and mice

N6-methyladenosine (m6A), the most abundant mRNA modification in eukaryotes, plays an essential role in regulating gene expression. Our prior research, alongside that of others, demonstrated that conditional uterine knockout of methyltransferase-like 3 (METTL3), the enzyme responsible for m6A modification, led to complete failure of embryo implantation and decidualization. Intriguingly, METTL3 expression is downregulated rather than upregulated in human endometrial stromal cells (HESCs) during in vitro decidualization and in mouse decidual tissues during pregnancy. We hypothesized that this decline in METTL3 expression is indispensable for successful decidualization. To test this hypothesis, we overexpressed METTL3 in HESCs and observed impaired decidualization in vitro. Additionally, we generated genetically engineered mice with uterine-specific METTL3 overexpression using Pgr-Cre, which exhibited subfertility mainly due to impaired decidualization. Further investigation revealed a marked decrease in HAND2, a well-established regulator of decidualization, following METTL3 overexpression. Mechanistically, we uncovered that METTL3 destabilizes HAND2 mRNA via m6A modification at the 5'-UTR. In summary, our study underscores the critical role of programmed METTL3 downregulation in decidualization by sustaining HAND2 expression.

physiology↗

CTCF is crucial for decidualization of uterine stromal cells through facilitating HOXA11 expression

CCCTC-binding factor (CTCF), a highly versatile transcriptional regulator and chromatin architectural protein, plays a pivotal role in mammalian development. In this study, we investigated the function of CTCF in uterine biology during pregnancy. We observed that CTCF expression in the human endometrium decreases from the proliferative to the secretory phase of the menstrual cycle. Similarly, in cultured human endometrial stromal cells (hESCs), CTCF expression declines during in vitro decidualization. Using siRNA-mediated knockdown, we demonstrated that CTCF is essential for the early phase of decidualization but dispensable in later stages. Notably, CTCF depletion reduces the expression of HOXA11, a well-established regulator of decidualization, and overexpression of HOXA11 rescues the decidualization defects caused by CTCF loss, identifying HOXA11 as a key downstream effector of CTCF. Mechanistically, CTCF binds to the HOXA11 promoter to facilitate its transcriptional activation. Furthermore, uterine-specific knockout of CTCF in Pgr-Cre mice leads to female infertility, characterized by diminished HOXA11 expression, impaired uterine receptivity, and defective decidualization. Collectively, our findings highlight the critical role of the CTCF-HOXA11 axis in decidualization in both humans and mice, providing novel insights into the molecular regulation of this process and potential therapeutic targets for reproductive disorders.

physiology↗

NAT10 governs uterine function and fertility by stabilizing progesterone receptor mRNA via ac4C modification

The N4-acetylcytidine (ac4C) modification is one of the most abundant chemical modifications in mammalian transcriptome, which plays a crucial role in regulating gene expression across various biological processes. In this study, we investigate the role of N4-acetyltransferase 10 (NAT10), the sole enzyme responsible for catalyzing the ac4C modification, in uterine function. Our findings revealed that knockdown of NAT10 in cultured human endometrial stromal cells leads to decreased progesterone receptor (PGR) expression and compromised decidualization. Mechanistically, NAT10 is found to enhance the stability of PGR mRNA through its ac4C modification in the coding sequence (CDS). Furthermore, conditional deletion of Nat10 in the mouse uterus using Pgr-Cre resulted in defective pubertal uterine development, characterized by a thinner stroma and reduced endometrial gland number. These mice were infertile in adulthood, experiencing failures in both implantation and decidualization. However, heterozygous Nat10 conditional knockout mice showed reduced NAT10 expression in the uterus without affecting uterine development or fertility. To bridge the gap between heterozygous and homozygous knockout conditions, we employed Remodelin, an inhibitor of NAT10, in adult female mice, to mimic an intermediate gene dosage. Our results demonstrated that inhibiting NAT10 with Remodelin preserved uterine structures but disrupted the PGR signaling pathway, leading to impaired uterine function during pregnancy. In conclusion, our study provides compelling evidence that NAT10 safeguards uterine function and fertility by regulating the ac4C modification of PGR mRNA. SignificanceHere we identified NAT10-catalyzed ac4C modification of progesterone receptor (PGR) mRNA as a crucial mechanism regulating PGR expression by enhancing its mRNA stability. In vitro studies using human endometrial stromal cells show that the NAT10-PGR axis is required for decidualization. Additionally, genetic and pharmacologic manipulations in mice further demonstrate the necessity of NAT10-dependent P4/PGR signaling for uterine function during implantation and decidualization. Our findings highlight the importance of NAT10-mediated ac4C modification in maintaining PGR expression and uterine function.

physiology↗