Biology subjects

Zhang, A.-N.

Publications and source records attributed to Zhang, A.-N..

4 recordsLinked to original sources

bioRxiv2025

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↗

bioRxiv2025

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↗

bioRxiv2023

Temporal dynamics of gut microbiomes in non-industrialized urban Amazonia

BackgroundIncreasing levels of industrialization have been associated with changes in gut microbiome structure and loss of features thought to be crucial for maintaining gut ecological balance. The stability of gut microbial communities over time within individuals seems to be largely affected by this transition but has been overlooked among transitioning populations from low to middle-income countries. Here, we used shotgun sequencing to characterize the temporal dynamics of gut microbiomes of 24 individuals living in an urban non-industrialized lifestyle in the Brazilian Amazon and contextualized our data with 165 matching longitudinal samples from an urban industrialized and a rural non-industrialized population. ResultsWe show that gut microbiome composition and diversity have greater variability over time among non-industrialized individuals when compared to industrialized counterparts and that taxa may present diverse temporal dynamics across human populations. Enterotype classifications show community types are generally stable over time despite shifts in microbiome structure. Further, by tracking genomes over time, we show that levels of bacterial population replacements are more frequent among Amazonian individuals and non-synonymous variants accumulate in genes associated with degradation of host dietary polysaccharides. ConclusionsOur results suggest that the stability of gut microbiomes is influenced by levels of industrialization and that tracking microbial population dynamics is important to understand how the microbiome will adapt to these transitions.

microbiology↗

bioRxiv2019

Choosing Your Battles: Which Resistance Genes Warrant Global Action?

The increasing accumulation of antibiotic resistance genes (ARGs) in pathogens poses a severe threat to the treatment of bacterial infections. However, not all ARGs do not pose the same threats to human health. Here, we present a framework to rank the risk of ARGs based on three factors: \"anthropogenic enrichment\", \"mobility\", and \"host pathogenicity\". The framework is informed by all available bacterial genomes (55,000), plasmids (16,000), integrons (3,000), and 850 metagenomes covering diverse global eco-habitats. The framework prioritizes 3% of all known ARGs in Rank I (the most at risk of dissemination amongst pathogens) and 0.3% of ARGs in Rank II (high potential emergence of new resistance in pathogens). We further validated the framework using a list of 38 ARG families previously identified as high risk by the World Health Organization and published literature, and found that 36 of them were properly identified as top risk (Rank I) in our approach. Furthermore, we identified 43 unreported Rank I ARG families that should be prioritized for public health interventions. Within the same gene family, homologous genes pose different risks, host range, and ecological distributions, indicating the need for high resolution surveillance into their sequence variants. Finally, to help strategize the policy interventions, we studied the impact of industrialization on high risk ARGs in 1,120 human gut microbiome metagenomes of 36 diverse global populations. Our findings suggest that current policies on controlling the clinical antimicrobial consumptions could effectively control Rank I, while greater antibiotic stewardship in veterinary settings could help control Rank II. Overall, our framework offered a straightforward evaluation of the risk posed by ARGs, and prioritized a shortlist of current and emerging threats for global action to fight ARGs.

microbiology↗