👤 En-Guang Dou

Excessive fluoride exposure induces skeletal fluorosis, but the specific mechanism responsible is still unclear. Therefore, this study aimed to identify the pathogenesis of fluoride-induced bone injuries. We systematically searched fluoride-induced bone injury-related genes from five databases. Then, these genes were subjected to enrichment analyses. A TF (transcription factor)-mRNA-miRNA network and protein-protein interaction (PPI) network were constructed using Cytoscape, and the Human Protein Atlas (HPA) database was used to screen the expression of key proteins. The candidate pharmacological targets were predicted using the Drug Signature Database. A total of 85 studies were included in this study, and 112 osteoblast-, 35 osteoclast-, and 41 chondrocyte-related differential expression genes (DEGs) were identified. Functional enrichment analyses showed that the Atf4, Bcl2, Col1a1, Fgf21, Fgfr1 and Il6 genes were significantly enriched in the PI3K-Akt signaling pathway of osteoblasts, Mmp9 and Mmp13 genes were enriched in the IL-17 signaling pathway of osteoclasts, and Bmp2 and Bmp7 genes were enriched in the TGF-beta signaling pathway of chondrocytes. With the use of the TF-mRNA-miRNA network, the Col1a1, Bcl2, Fgfr1, Mmp9, Mmp13, Bmp2, and Bmp7 genes were identified as the key regulatory factors. Selenium methyl cysteine, CGS-27023A, and calcium phosphate were predicted to be the potential drugs for skeletal fluorosis. These results suggested that the PI3K-Akt signaling pathway being involved in the apoptosis of osteoblasts, with the IL-17 and the TGF-beta signaling pathways being involved in the inflammation of osteoclasts and chondrocytes in fluoride-induced bone injuries. Show less

Poultry is a source of meat that is in great demand in the world. The quality of meat is an imperative point for shoppers. To explore the genes controlling meat quality characteristics, the growth and meat quality traits and muscle transcriptome of two indigenous Yunnan chicken breeds, Wuding chickens (WDs) and Daweishan mini chickens (MCs), were compared with Cobb broilers (CBs). The growth and meat quality characteristics of these two indigenous breeds were found to differ from CB. In particular, the crude fat (CF), inosine monophosphate content, amino acid (AA), and total fatty acid (TFA) content of WDs were significantly higher than those of CBs and MCs. In addition, it was found that MC pectoralis had 420 differentially expressed genes (DEGs) relative to CBs, and WDs had 217 DEGs relative to CBs. Among them, 105 DEGs were shared. The results of 10 selected genes were also confirmed by qPCR. The differentially expressed genes were six enriched Kyoto Encyclopedia of Genes and Genomes (KEGG) biological pathways including lysosomes, phagosomes, PPAR signaling pathways, cell adhesion molecules, cytokine-cytokine receptor interaction, and phagosome sphingolipid metabolism. Interestingly, four genes ( Show less

Histone H4 lysine 16 acetylation (H4K16ac), governed by the histone acetyltransferase MOF, orchestrates gene expression regulation and chromatin interaction. However, the roles of MOF and H4K16ac in controlling cellular function and regulating mammalian tissue development remain unclear. Here we show that conditional deletion of Mof in the skin, but not Kansl1, causes severe defects in the self-renewal of basal epithelial progenitors, epidermal differentiation, and hair follicle growth, resulting in barrier defects and perinatal lethality. MOF-regulated genes are highly enriched for essential functions in the mitochondria and cilia. Genetic deletion of Uqcrq, an essential subunit for the electron transport chain (ETC) Complex III, in the skin, recapitulates the defects in epidermal differentiation and hair follicle growth observed in MOF knockout mouse. Together, this study reveals the requirement of MOF-mediated epigenetic mechanism for regulating mitochondrial and ciliary gene expression and underscores the important function of the MOF/ETC axis for mammalian skin development. Show less

The RNA-binding ARS2 protein is centrally involved in both early RNA polymerase II (RNAPII) transcription termination and transcript decay. Despite its essential nature, the mechanisms by which ARS2 enacts these functions have remained unclear. Here, we show that a conserved basic domain of ARS2 binds a corresponding acidic-rich, short linear motif (SLiM) in the transcription restriction factor ZC3H4. This interaction recruits ZC3H4 to chromatin to elicit RNAPII termination, independent of other early termination pathways defined by the cleavage and polyadenylation (CPA) and Integrator (INT) complexes. We find that ZC3H4, in turn, forms a direct connection to the nuclear exosome targeting (NEXT) complex, hereby facilitating rapid degradation of the nascent RNA. Hence, ARS2 instructs the coupled transcription termination and degradation of the transcript onto which it is bound. This contrasts with ARS2 function at CPA-instructed termination sites where the protein exclusively partakes in RNA suppression via post-transcriptional decay. Show less

Understanding heat stress physiology and identifying reliable biomarkers are paramount for developing effective management and mitigation strategies. However, little is known about the molecular mechanisms underlying thermal tolerance in animals. In an experimental model of Sprague-Dawley rats subjected to temperatures of 22 ± 1°C (control group; CT) and 42°C for 30 min (H30), 60 min (H60), and 120 min (H120), RNA-sequencing (RNA-Seq) assays were performed for blood (CT and H120), liver (CT, H30, H60, and H120), and adrenal glands (CT, H30, H60, and H120). A total of 53, 1,310, and 1,501 differentially expressed genes (DEGs) were significantly identified in the blood ( Show less

In view of the negative regulatory effect of leucine-rich repeat and immunoglobulin-like domain-containing nogo receptor-interacting protein 1 (LINGO-1) on neurons, an antibody against LINGO-1 (anti-LINGO-1 antibody) was herein administered to 10-month-old APP/PS1 transgenic Alzheimer's disease (AD) mice for 2 months as an experimental intervention. Behavioral, stereology, immunohistochemistry and immunofluorescence analyses revealed that the anti-LINGO-1 antibody significantly improved the cognitive abilities, promoted adult hippocampal neurogenesis (AHN), decreased the amyloid beta (Aβ) deposition, enlarged the hippocampal volume, and increased the numbers of total neurons and GABAergic interneurons, including GABAergic and CCK-GABAergic interneurons rich in cannabinoid type 1 receptor (CB1R), in the hippocampus of AD mice. In contrast, this intervention significantly reduced the number of GABAergic interneurons expressing LINGO-1 and CB1R in the hippocampus of AD mice. More importantly, we also found a negative correlation between LINGO-1 and CB1R on GABAergic interneurons in the hippocampus of AD mice, while the anti-LINGO-1 antibody reversed this relationship. These results indicated that LINGO-1 plays an important role in the process of hippocampal neuron loss in AD mice and that antagonizing LINGO-1 can effectively prevent hippocampal neuron loss and promote AHN. The improvement in cognitive abilities may be attributed to the improvement in AHN, and in the numbers of GABAergic interneurons and CCK-GABAergic interneurons rich in CB1Rs in the hippocampus of AD mice induced by the anti-LINGO-1 antibody. Collectively, the double target effect (LINGO-1 and CB1R) initiated by the anti-LINGO-1 antibody may provide an important basis for the study of drugs for the prevention and treatment of AD in the future. Show less

The ascites that develops in advanced OC, both at diagnosis and upon recurrence, is a rich source of multicellular spheroids/aggregates (MCSs/MCAs), which are the major seeds of tumor cell dissemination within the abdominal cavity. However, the molecular mechanism by which specific ascites-derived tumor cells survive and metastasize remains largely unknown. In this study, we elucidated cancer stem cell (CSC) properties of ascites-derived MCSs, concomitant with enhanced malignancy, induced EMT, and low KLF9 (Krüppel-like factor 9) expression, compared with PTCs. KLF9 was also downregulated in OC cell line-derived spheroids and the CD117 Show less

Sepsis induces the release of lipid mediators, which control both lipid metabolism and inflammation. However, the role of serum apolipoprotein A-V (ApoA5) in sepsis is poorly understood in pediatric patients. ApoA5 was screened from serum proteomics profile in lipopolysaccharide- (LPS-) treated mice for 2 h, 24 h, and controls. Then, we conducted a prospective pilot study, and patients with sepsis admitted to a pediatric intensive care unit (PICU) were enrolled from January 2018 to December 2018. Serum ApoA5 levels on PICU admission were determined using enzyme-linked immunosorbent assays (ELISA). Blood samples from 30 healthy children were used as control. The correlation of ApoA5 with the clinical and laboratory parameters was analyzed. Logistic regression analyses and receiver operating characteristic curve (ROC) analysis were used to investigate the potential role of serum ApoA5 as a prognostic predictor for PICU mortality in pediatric patients with sepsis. A total of 101 patients with sepsis were enrolled in this study. The PICU mortality rate was 10.9% (11/101). Serum ApoA5 levels on PICU admission were significantly lower in nonsurvivors with sepsis compared with survivors ( Serum ApoA5 level is associated with sepsis-associated shock, AKI, ALI, GI dysfunction, or MODS in children. Moreover, the findings of the present study suggest a prognostic value of ApoA5 in children with sepsis, and lower serum ApoA5 than 822 ng/mL predicts worse outcome in pediatric sepsis. Show less

The microtubule actin cross-linking factor 1 (MACF1) is involved in cellular migration, adhesion, and invasion processes. Its abnormal expression initiates tumor cell proliferation and metastasis in numerous cancer types. In this study, we utilized short hair-pin RNA interference of MACF1 to assess the inhibitory effects on the metastatic potential of B16F10 melanoma cells both in vitro and in vivo a mouse model. The MACF1 expression was increased in B16F10 cells-induced tumor tissues; while the down-regulation of MACF1 impacted the B16F10 melanoma cell metastatic behavior by decreasing the ability of colony formation and invasion in vitro as well as inhibiting B16F10 cells-induced tumor growth and lung metastasis in vivo. The results of Western blot and immunohistochemistry indicated that the expression of E-cadherin and Smad-7 was significantly increased whereas the expression of N-cadherin and TGF-β1 was significantly decreased in tumor tissue of mice challenged with the B16F10/MACF1-RNAi cells when compared with the B16F10 cells challenged mice. The data presented in this study demonstrated that down-regulated MACF1 expression decreased B16F10 melanoma metastasis in mice by inhibiting the epithelial to mesenchymal transition program. Thus, MACF1 may be a novel target for melanoma therapy. Show less

Numb is a conserved protein plays important roles in the development of cancer. Two Numb isoforms have been found produced by alternative splicing and play contrast roles in regulating cellular functions. It is reported that the expression of Numb long isoform (Numb-L) was increased in various kinds of cancers, but in endometrial cancer, the condition is still unknown. The level of two Numb transcripts and protein isoforms were detected by semiquantitative polymerase chain reaction and immunoblotting in 47 paired endometrial tumor and adjacent non-tumor control tissues. The level of three alternative splicing related proteins: RBM5, RBM6, and RBM10 was determined by immunoblotting. MiRNAs targeting RBM10 were predicted by bioinformatics tools and their interaction with RBM10 was confirmed by luciferase assay and immunoblotting. The function of miR-335 in endometrial cancer was examined in xenograft mouse model. Numb-L level was increased in tumors and negatively correlated with RBM10 protein level. RBM10 mRNA level was not significantly altered in endometrial tumors suggesting its expression may regulated by post transcriptional regulators such as miRNAs. We identified miR-133a, miR-133b, and miR-335 directly target RBM10, but only miR-335 level increased in tumors and negatively correlated with RBM10 protein level. miR-335 overexpression promoted tumor growth by downregulating RBM10 and upregulating Numb-L level in xenograft mouse model. miR-335 overexpression promoted Numb-L expression via targeting RBM10 in endometrial cancer, which may provide new biomarkers for EC diagnosis. Show less

Vascular endothelial growth factor A (VEGFA) gene has three alternative exons which results in multiple isoforms. VEGFA has been found overexpressed in patients with endometrial cancer, but the VEGFA expression pattern and how it is regulated are still unknown. The level of VEGFA transcripts and protein isoforms were detected by semi-quantitative Polymerase chain reaction (PCR) and immunoblotting in 29 paired endometrial tumor and adjacent nontumor control tissues. The level of three alternative splicing related proteins: RBM5, RBM6, and RBM10 was determined by immunoblotting. The H3K27Ac level in RBM10 promoter region was detected by ChIP-PCR. The RBM10 promoter region methylation level were quantified by methylation-sensitive high resolution melting. VEGFA165a was overexpressed and VEGFA165b level was reduced in tumors. RBM10 level was reduced in tumors. RBM10 level was negatively correlated with VEGFA165a level and positively correlated with VEGFA165b level in tumors. Using HEC-1-A and RL95-2 cells, we confirmed that VEGFA165a/b expressed pattern was controlled by RBM10. MALAT1 level was increased in tumors but not involved in VEGFA alternative splicing. Reduced H3K27Ac level and increased DNA methylation in the promoter region controlled RBM10 expression in tumors. VEGFA alternative splicing in endometrial cancer was regulated by RBM10, the expression of which was controlled by histone acetylation and DNA methylation. Show less

Breast cancer stem cells (BCSCs) are typically seed cells of breast tumor that initiate and maintain tumor growth. MiR-7, as a cancer inhibitor, decreases the BCSC subset and inhibits tumor progression through mechanisms that remain unknown. We examined miR-7 expression in breast cancer and developed a BCSC-driven xenograft mouse model, to evaluate the effects of miR-7 overexpression on the decrease of the BCSC subset in vitro and in vivo. In addition, we determined how miR-7 decreased the BCSC subset by using the ALDEFLUOR, lentivirus infection, dual-luciferase reporter, and chromatin immunoprecipitation-PCR assays. MiR-7 was expressed at low levels in breast cancer tissues compared with normal tissues, and overexpression of miR-7 directly inhibited lncRNA XIST, which mediates the transcriptional silencing of genes on the X chromosome, and reduced epithelium-specific antigen (ESA) expression by increasing miR-92b and inhibiting slug. Moreover, miR-7 suppressed CD44 and ESA by directly inhibiting the NF-κB subunit RELA and slug in breast cancer cell lines and in BCSC-driven xenografts, which confirmed the antitumor activity in mice injected with miR-7 agomir or stably infected with lenti-miR-7. The findings from this study uncover the molecular mechanisms by which miR-7 inhibits XIST, modulates the miR-92b/Slug/ESA axis, and decreases the RELA and CD44 expression, resulting in a reduced BCSC subset and breast cancer growth inhibition. These findings suggest a potentially targeted treatment approach to breast cancer. Show less

Helicase DHX36 plays essential roles in cell development and differentiation at least partially by resolving G-quadruplex (G4) structures. Here we report crystal structures of the Drosophila homolog of DHX36 (DmDHX36) in complex with RNA and a series of DNAs. By combining structural, small-angle X-ray scattering, molecular dynamics simulation, and single-molecule fluorescence studies, we revealed that positively charged amino acids in RecA2 and OB-like domains constitute an elaborate structural pocket at the nucleic acid entrance, in which negatively charged G4 DNA is tightly bound and partially destabilized. The G4 DNA is then completely unfolded through the 3'-5' translocation activity of the helicase. Furthermore, crystal structures and DNA binding assays show that G-rich DNA is preferentially recognized and in the presence of ATP, specifically bound by DmDHX36, which may cooperatively enhance the G-rich DNA translocation and G4 unfolding. On the basis of these results, a conceptual G4 DNA-resolving mechanism is proposed. Show less

To investigate the clinical characteristics of patients with hypertriglyceridemic acute pancreatitis (HTGAP), and the molecular foundation contributing to hypertriglyceridemia in such patients. Clinical data from 329 patients with acute pancreatitis (AP) were analyzed. The patients were divided into the HTGAP group, with fasting serum triglyceride (TG) levels ≥500 mg/dL (5.65 mmol/L), and the non-HTGAP (NHTGAP) group. Targeted next-generation sequencing was applied to 11 HTGAP patients to identify the genetic mutations associated with hypertriglyceridemia, including apolipoprotein A-V (APOA5), APOC2, APOC3 and APOE, BLK, LPL, GPIHBP1 and LMF1. Patients in the HTGAP group, compared with those in the NHTGAP group, had a higher mortality rate (7.5% vs 0.7%, P = 0.001), more commonly seen severe AP (17.5% vs 5.2%, P = 0.004) as well as a higher recurrence rate (32.4% vs 19.9%, P = 0.070). DNA sequencing showed that two patients carried the same compound of p.G185C and p.V153M heterozygous mutations located in the APOA5 gene. Two patients carried a homozygous variation of p.C14F, in the GPIHBP1 gene. One patient had a homozygous variation of p.R176C in the APOE gene. And a rare heterozygous LMF1 gene mutation of p.P562R was detected in two patients. HTGAP was significantly severe than NHTGAP, with a high recurrence rate. Genetic information may be useful in the clinical setting for the investigation of the pathogenesis of HTGAP and its interventions. Show less

The class III phosphoinositide 3-kinase (PI3K) Vps34 (also known as PIK3C3 in mammals) produces phosphatidylinositol 3-phosphate [PI(3)P] on both early and late endosome membranes to control membrane dynamics. We used Vps34-deficient cells to delineate whether Vps34 has additional roles in endocytic trafficking. In Vps34 Show less

PIK3C3/Vps34 is the class III PtdIns3K that is evolutionarily conserved from yeast to mammals. Its central role in mammalian autophagy has been suggested through the use of pharmacological inhibitors and the study of its binding partners. However, the precise role of PIK3C3 in mammals is not clear. Using mouse strains that allow tissue-specific deletion of PIK3C3, we have described an essential role of PIK3C3 in regulating autophagy, and liver and heart function. Show less

A critical regulator of autophagy is the Class III PI3K Vps34 (also called PIK3C3). Although Vps34 is known to play an essential role in autophagy in yeast, its role in mammals remains elusive. To elucidate the physiological function of Vps34 and to determine its precise role in autophagy, we have generated Vps34(f/f) mice, in which expression of Cre recombinase results in a deletion of exon 4 of Vps34 and a frame shift causing a deletion of 755 of the 887 amino acids of Vps34. Acute ablation of Vps34 in MEFs upon adenoviral Cre infection results in a diminishment of localized generation of phosphatidylinositol 3-phosphate and blockade of both endocytic and autophagic degradation. Starvation-induced autophagosome formation is blocked in both Vps34-null MEFs and liver. Liver-specific Albumin-Cre;Vps34(f/f) mice developed hepatomegaly and hepatic steatosis, and impaired protein turnover. Ablation of Vps34 in the heart of muscle creatine kinase-Cre;Vps34(f/f) mice led to cardiomegaly and decreased contractility. In addition, while amino acid-stimulated mTOR activation was suppressed in the absence of Vps34, the steady-state level of mTOR signaling was not affected in Vps34-null MEFs, liver, or cardiomyocytes. Taken together, our results indicate that Vps34 plays an essential role in regulating functional autophagy and is indispensable for normal liver and heart function. Show less