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1.
Nucleic Acids Res ; 2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39166489

RESUMEN

Chromatin changes in response to estrogen and progesterone are well established in cultured cells, but how they control gene expression under physiological conditions is largely unknown. To address this question, we examined in vivo estrous cycle dynamics of mouse uterus hormone receptor occupancy, chromatin accessibility and chromatin structure by combining RNA-seq, ATAC-seq, HiC-seq and ChIP-seq. Two estrous cycle stages were chosen for these analyses, diestrus (highest estrogen) and estrus (highest progesterone). Unexpectedly, rather than alternating with each other, estrogen receptor alpha (ERα) and progesterone receptor (PGR) were co-bound during diestrus and lost during estrus. Motif analysis of open chromatin followed by hypoxia inducible factor 2A (HIF2A) ChIP-seq and conditional uterine deletion of this transcription factor revealed a novel role for HIF2A in regulating diestrus gene expression patterns that were independent of either ERα or PGR binding. Proteins in complex with ERα included PGR and cohesin, only during diestrus. Combined with HiC-seq analyses, we demonstrate that complex chromatin architecture changes including enhancer switching are coordinated with ERα and PGR co-binding during diestrus and non-hormone receptor transcription factors such as HIF2A during estrus to regulate most differential gene expression across the estrous cycle.

2.
Diabet Med ; 41(6): e15279, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38185936

RESUMEN

AIMS: Evidence is accumulating of the therapeutic benefits of mesenchymal stromal cells (MSCs) in diabetes-related conditions. We have identified a novel population of stromal cells within islets of Langerhans - islet stellate cells (ISCs) - which have a similar morphology to MSCs. In this study we characterize mouse ISCs and compare their morphology and function to MSCs to determine whether ISCs may also have therapeutic potential in diabetes. METHODS: ISCs isolated from mouse islets were compared to mouse bone marrow MSCs by analysis of cell morphology; expression of cell-surface markers and extracellular matrix (ECM) components; proliferation; apoptosis; paracrine activity; and differentiation into adipocytes, chondrocytes and osteocytes. We also assessed the effects of co-culture with ISCs or MSCs on the insulin secretory capacity of islet beta cells. RESULTS: Although morphological similar, ISCs were functionally distinct from MSCs. Thus, ISCs were less proliferative and more apoptotic; they had different expression levels of important paracrine factors; and they were less efficient at differentiation down multiple lineages. Co-culture of mouse islets with ISCs enhanced glucose induced insulin secretion more effectively than co-culture with MSCs. CONCLUSIONS: ISCs are a specific sub-type of islet-derived stromal cells that possess biological behaviors distinct from MSCs. The enhanced beneficial effects of ISCs on islet beta cell function suggests that they may offer a therapeutic target for enhancing beta cell functional survival in diabetes.


Asunto(s)
Diferenciación Celular , Técnicas de Cocultivo , Células Secretoras de Insulina , Islotes Pancreáticos , Células Madre Mesenquimatosas , Animales , Ratones , Células Madre Mesenquimatosas/metabolismo , Células Madre Mesenquimatosas/fisiología , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/fisiología , Células Secretoras de Insulina/citología , Diferenciación Celular/fisiología , Islotes Pancreáticos/citología , Islotes Pancreáticos/metabolismo , Células Estrelladas Pancreáticas/metabolismo , Células Estrelladas Pancreáticas/fisiología , Proliferación Celular/fisiología , Insulina/metabolismo , Células Cultivadas , Secreción de Insulina/fisiología , Ratones Endogámicos C57BL , Masculino , Apoptosis/fisiología
3.
Biomacromolecules ; 25(6): 3475-3485, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38741285

RESUMEN

Material reinforcement commonly exists in a contradiction between strength and toughness enhancement. Herein, a reinforced strategy through self-assembly is proposed for alginate fibers. Sodium alginate (SA) microstructures with regulated secondary structures are assembled in acidic and ethanol as reinforcing units for alginate fibers. Acidity increases the flexibility of the helix and contributes to enhanced extendibility. Ethanol is responsible for formation of a stiff ß-sheet, which enhances the modulus and strength. The structurally engineered SA assembly exhibits robust mechanical compatibility, and thus reinforced alginate fibers possess an improved tensile strength of 2.1 times, a prolonged elongation of 1.5 times, and an enhanced toughness of 3.0 times compared with SA fibers without reinforcement. The reinforcement through self-assembly provides an understanding of strengthening and toughening mechanism based on secondary structures. Due to a similar modulus with bones, reinforced alginate fibers exhibit good efficacy in accelerating bone regeneration in vivo.


Asunto(s)
Alginatos , Regeneración Ósea , Resistencia a la Tracción , Alginatos/química , Regeneración Ósea/efectos de los fármacos , Animales , Materiales Biocompatibles/química , Ácido Glucurónico/química , Ensayo de Materiales , Ácidos Hexurónicos/química , Andamios del Tejido/química
4.
Mol Cell ; 61(2): 199-209, 2016 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-26725009

RESUMEN

Mitochondrial metabolism is necessary for the maintenance of oxidative TCA cycle function and mitochondrial membrane potential. Previous attempts to decipher whether mitochondria are necessary for biological outcomes have been hampered by genetic and pharmacologic methods that simultaneously disrupt multiple functions linked to mitochondrial metabolism. Here, we report that inducible depletion of mitochondrial DNA (ρ(ο) cells) diminished respiration, oxidative TCA cycle function, and the mitochondrial membrane potential, resulting in diminished cell proliferation, hypoxic activation of HIF-1, and specific histone acetylation marks. Genetic reconstitution only of the oxidative TCA cycle function specifically in these inducible ρ(ο) cells restored metabolites, resulting in re-establishment of histone acetylation. In contrast, genetic reconstitution of the mitochondrial membrane potential restored ROS, which were necessary for hypoxic activation of HIF-1 and cell proliferation. These results indicate that distinct mitochondrial functions associated with respiration are necessary for cell proliferation, epigenetics, and HIF-1 activation.


Asunto(s)
Ciclo del Ácido Cítrico , Potencial de la Membrana Mitocondrial , Acetilación , Proliferación Celular , Respiración de la Célula , ADN Polimerasa gamma , ADN Mitocondrial/metabolismo , ADN Polimerasa Dirigida por ADN/metabolismo , Células HEK293 , Histonas/metabolismo , Humanos , Factor 1 Inducible por Hipoxia/metabolismo , Metaboloma , Proteínas Mitocondriales/metabolismo , Oxidación-Reducción , Oxidorreductasas/metabolismo , Consumo de Oxígeno , Proteínas de Plantas/metabolismo , Estabilidad Proteica , Especies Reactivas de Oxígeno/metabolismo
5.
Proc Natl Acad Sci U S A ; 118(11)2021 03 16.
Artículo en Inglés | MEDLINE | ID: mdl-33707208

RESUMEN

Uterine contractile dysfunction leads to pregnancy complications such as preterm birth and labor dystocia. In humans, it is hypothesized that progesterone receptor isoform PGR-B promotes a relaxed state of the myometrium, and PGR-A facilitates uterine contraction. This hypothesis was tested in vivo using transgenic mouse models that overexpress PGR-A or PGR-B in smooth muscle cells. Elevated PGR-B abundance results in a marked increase in gestational length compared to control mice (21.1 versus 19.1 d respectively, P < 0.05). In both ex vivo and in vivo experiments, PGR-B overexpression leads to prolonged labor, a significant decrease in uterine contractility, and a high incidence of labor dystocia. Conversely, PGR-A overexpression leads to an increase in uterine contractility without a change in gestational length. Uterine RNA sequencing at midpregnancy identified 1,174 isoform-specific downstream targets and 424 genes that are commonly regulated by both PGR isoforms. Gene signature analyses further reveal PGR-B for muscle relaxation and PGR-A being proinflammatory. Elevated PGR-B abundance reduces Oxtr and Trpc3 and increases Plcl2 expression, which manifests a genetic profile of compromised oxytocin signaling. Functionally, both endogenous PLCL2 and its paralog PLCL1 can attenuate uterine muscle cell contraction in a CRISPRa-based assay system. These findings provide in vivo support that PGR isoform levels determine distinct transcriptomic landscapes and pathways in myometrial function and labor, which may help further the understanding of abnormal uterine function in the clinical setting.


Asunto(s)
Regulación de la Expresión Génica/fisiología , Péptidos y Proteínas de Señalización Intracelular/genética , Receptores de Oxitocina/genética , Receptores de Progesterona/fisiología , Canales Catiónicos TRPC/genética , Contracción Uterina/genética , Animales , Femenino , Ratones , Ratones Mutantes , Parto/fisiología , Embarazo , Receptores de Progesterona/genética , Receptores de Progesterona/metabolismo , Transcriptoma
6.
Opt Express ; 31(8): 13428-13435, 2023 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-37157481

RESUMEN

Photoalignment of liquid crystal polarization grating based on optical imprinting is a promising technique for polarization grating mass production. However, when the period of the optical imprinting grating is in the sub-micrometer level, the zero-order energy from the master grating will become high, and it will strongly affect the photoalignment quality. This paper proposes a double-twisted polarization grating structure to eliminate the zero-order disturbance of master grating and gives the design method. Based on the designed results, a master grating was prepared, and the optically imprinted photoalignment of polarization grating with a period of 0.5µm was fabricated. This method has the advantages of high efficiency and significantly greater environmental tolerance than the traditional polarization holographic photoalignment methods. It has the potential to be used for large-area polarization holographic gratings production.

7.
Clin Lab ; 69(6)2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-37307133

RESUMEN

BACKGROUND: This study assessed the potential effect of combining micafungin and tobramycin in vitro against biofilms of clinical Pseudomonas aeruginosa isolates. METHODS: Nine biofilm-positive clinical isolates of P. aeruginosa were used in this study. The minimum inhibitory concentrations (MICs) of micafungin and tobramycin for planktonic bacteria were determined using the agar dilution method. The planktonic bacterial growth curve was plotted for micafungin treatment. Biofilms of these nine strains were treated with different concentrations of micafungin and combined with tobramycin in microtiter plates. Biofilm biomass was detected by crystal violet staining and spectrophotometry. Phenotypic reduction in biofilm formation and the eradication of mature biofilm were significant based on average optical density (p < 0.05). The kinetics of micafungin combined with tobramycin to eradicate mature biofilms was investigated in vitro using the time-kill method. RESULTS: Micafungin exhibited no antibacterial effect on P. aeruginosa, and tobramycin minimum inhibitory concentrations (MICs) did not change in the presence of micafungin. Micafungin alone inhibited biofilm formation and eradicated established biofilms of all isolates in a dose-dependent manner, but the required minimum concentration varied. An increase in micafungin concentration resulted in an observed inhibition rate of 64.9% - 72.3% and achieved an eradication rate of 59.2% - 64.5%. Its combination with tobramycin exhibited synergistic effects, including inhibiting the biofilm formation of PA02, PA05, PA23, PA24, and PA52 isolates above 1/4 × MIC or 1/2 × MIC and eradicating mature biofilms of PA02, PA04, PA23, PA24, and PA52 above 32 × MIC, 2 × MIC, 16 × MIC, 32 × MIC, and 1 × MIC, respectively. Micafungin addition could eradicate biofilm-embedded bacterial cells more rapidly; at 32 mg/L, the biofilm eradication time lowered from 24 hours to 12 hours for the inoculum groups with 106 CFU/mL, and from 12 hours to 8 hours for 105 CFU/mL. Whereas at 128 mg/L, the time was lowered from 12 hours to 8 hours for the inoculum groups with 106 CFU/mL, and from 8 hours to 4 hours for 105 CFU/mL. CONCLUSIONS: Micafungin showed good anti-biofilm activity at low concentrations. The combination of micafungin with tobramycin displayed a synergistic effect in controlling P. aeruginosa biofilm.


Asunto(s)
Pseudomonas aeruginosa , Tobramicina , Humanos , Micafungina , Antibacterianos , Biopelículas
8.
Am J Respir Crit Care Med ; 206(3): 321-336, 2022 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-35536696

RESUMEN

Rationale: Methylation integrates factors present at birth and modifiable across the lifespan that can influence pulmonary function. Studies are limited in scope and replication. Objectives: To conduct large-scale epigenome-wide meta-analyses of blood DNA methylation and pulmonary function. Methods: Twelve cohorts analyzed associations of methylation at cytosine-phosphate-guanine probes (CpGs), using Illumina 450K or EPIC/850K arrays, with FEV1, FVC, and FEV1/FVC. We performed multiancestry epigenome-wide meta-analyses (total of 17,503 individuals; 14,761 European, 2,549 African, and 193 Hispanic/Latino ancestries) and interpreted results using integrative epigenomics. Measurements and Main Results: We identified 1,267 CpGs (1,042 genes) differentially methylated (false discovery rate, <0.025) in relation to FEV1, FVC, or FEV1/FVC, including 1,240 novel and 73 also related to chronic obstructive pulmonary disease (1,787 cases). We found 294 CpGs unique to European or African ancestry and 395 CpGs unique to never or ever smokers. The majority of significant CpGs correlated with nearby gene expression in blood. Findings were enriched in key regulatory elements for gene function, including accessible chromatin elements, in both blood and lung. Sixty-nine implicated genes are targets of investigational or approved drugs. One example novel gene highlighted by integrative epigenomic and druggable target analysis is TNFRSF4. Mendelian randomization and colocalization analyses suggest that epigenome-wide association study signals capture causal regulatory genomic loci. Conclusions: We identified numerous novel loci differentially methylated in relation to pulmonary function; few were detected in large genome-wide association studies. Integrative analyses highlight functional relevance and potential therapeutic targets. This comprehensive discovery of potentially modifiable, novel lung function loci expands knowledge gained from genetic studies, providing insights into lung pathogenesis.


Asunto(s)
Metilación de ADN , Epigenoma , Islas de CpG , Metilación de ADN/genética , Epigénesis Genética/genética , Epigenómica , Estudio de Asociación del Genoma Completo , Humanos , Recién Nacido , Pulmón
9.
Int Wound J ; 21(3): e14477, 2023 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-37944931

RESUMEN

The purpose of this study is to determine the impact of maggot debridement therapy (MDT) on macrophages during the healing process of diabetic foot ulcers (DFU). The activation phenotype of macrophages during wound healing following MDT was evaluated using double staining immunohistochemistry (IHC). In addition, markers associated with macrophage activation were discovered using immunoblotting and real-time polymerase chain reaction (PCR). During the process of diabetic wound healing following MDT, the presence and over-expression of M2 macrophages were observed, while the under-expression of M1 macrophages was noted. In addition, the activation markers of macrophages exhibited a correlation with the indicated Th1/Th2 cytokines. MDT interventions have the potential to modulate macrophage activity, thereby aiding in the healing of diabetic foot wounds.

10.
Biol Reprod ; 107(2): 529-545, 2022 08 09.
Artículo en Inglés | MEDLINE | ID: mdl-35357464

RESUMEN

Uterine dysfunctions lead to fertility disorders and pregnancy complications. Normal uterine functions at pregnancy depend on crosstalk among multiple cell types in uterine microenvironments. Here, we performed the spatial transcriptomics and single-cell RNA-seq assays to determine local gene expression profiles at the embryo implantation site of the mouse uterus on pregnancy day 7.5 (D7.5). The spatial transcriptomic annotation identified 11 domains of distinct gene signatures, including a mesometrial myometrium, an anti-mesometrial myometrium, a mesometrial decidua enriched with natural killer cells, a vascular sinus zone for maternal vessel remodeling, a fetal-maternal interface, a primary decidual zone, a transition decidual zone, a secondary decidual zone, undifferentiated stroma, uterine glands, and the embryo. The scRNA-Seq identified 12 types of cells in the D7.5 uterus including three types of stromal fibroblasts with differentiated and undifferentiated markers, one cluster of epithelium including luminal and glandular epithelium, mesothelium, endothelia, pericytes, myelomonocytic cell, natural killer cells, and lymphocyte B. These single-cell RNA signatures were then utilized to deconvolute the cell-type compositions of each individual uterine microenvironment. Functional annotation assays on spatial transcriptomic data revealed uterine microenvironments with distinguished metabolic preferences, immune responses, and various cellular behaviors that are regulated by region-specific endocrine and paracrine signals. Global interactome among regions is also projected based on the spatial transcriptomic data. This study provides high-resolution transcriptome profiles with locality information at the embryo implantation site to facilitate further investigations on molecular mechanisms for normal pregnancy progression.


Asunto(s)
Transcriptoma , Útero , Animales , Decidua/fisiología , Implantación del Embrión/genética , Epitelio , Femenino , Células Asesinas Naturales , Ratones , Miometrio , Embarazo , Útero/metabolismo
11.
Inorg Chem ; 61(17): 6488-6492, 2022 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-35426655

RESUMEN

Lead-free halide double perovskites (DPs) have been proposed as stable and promising alternatives to lead halide perovskites. Understanding the structural-optical properties of halide DPs is important for their applications. In this study, Cs2AgInCl6 DP nanocrystals, with a direct band gap, were synthesized and studied. Because of a strong electron-phonon coupling leading to exciton self-trapping, a broad emission with a large Stokes shift of Cs2AgInCl6 DP nanocrystals is observed. We observed an abnormal blue-shifted emission accompanied by a red-shifted direct absorption edge because of the reduced electron-phonon coupling under compression in the cubic phase Cs2AgInCl6 DP nanocrystals. Our study clarified the basic structural-optical correlation of halide DPs and may promote their application in related fields.

12.
Entropy (Basel) ; 24(4)2022 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-35455129

RESUMEN

Vehicles carrying hazardous material (hazmat) are severe threats to the safety of highway transportation, and a model that can automatically recognize hazmat markers installed or attached on vehicles is essential for intelligent management systems. However, there is still no public dataset for benchmarking the task of hazmat marker detection. To this end, this paper releases a large-scale vehicle hazmat marker dataset named VisInt-VHM, which includes 10,000 images with a total of 20,023 hazmat markers captured under different environmental conditions from a real-world highway. Meanwhile, we provide an compact hazmat marker detection network named HMD-Net, which utilizes a revised lightweight backbone and is further compressed by channel pruning. As a consequence, the trained-model can be efficiently deployed on a resource-restricted edge device. Experimental results demonstrate that compared with some established methods such as YOLOv3, YOLOv4, their lightweight versions and popular lightweight models, HMD-Net can achieve a better trade-off between the detection accuracy and the inference speed.

13.
Zhongguo Zhong Yao Za Zhi ; 47(11): 3088-3094, 2022 Jun.
Artículo en Zh | MEDLINE | ID: mdl-35718533

RESUMEN

The present study evaluated the efficacy and safety of Shuxuetong Injection in the treatment of diabetic peripheral neuropathy(DPN). PubMed, Cochrane Library, EMbase, CNKI, VIP, SinoMed, and Wanfang were searched for randomized controlled trials(RCTs) of Shuxuetong Injection in the treatment of DPN from database inception to July 18, 2021. Literature screening was carried out according to the inclusion and exclusion criteria, and the required information was extracted. Cochrane risk-of-bias tool was used to evaluate the quality of the included trials, and RevMan 5.3 was used for Meta-analysis. Finally, six articles were included, involving 507 patients. The overall quality of included RCTs was not high. As revealed by Meta-analysis results, in terms of DPN score, one trial showed a significant difference in the experimental group before and after treatment, and the symptom of the experimental group was significantly improved compared with that in the control group after treatment. After treatment, a significant difference in DPN scores of the experimental group and the control group was observed(P<0.05), and the symptom improvement of the experimental group was significantly better than that of the control group. In terms of sensory nerve conduction velocity(SCV), the experimental group was superior to the control group in improving conduction velocities(MD_(median SCV)=4.45, 95%CI[2.79, 6.10], P<0.000 01; MD_(peroneal SCV)=6.70, 95%CI[5.64, 7.75], P<0.000 01; MD_(posterior tibial SCV)=4.03, 95%CI[0.56, 7.49], P=0.02). In terms of motor nerve conduction velocity(MCV), compared with the conditions before treatment, the conduction velocities of median nerve, peroneal nerve, and posterior tibial nerve in both groups increased after treatment(P<0.01). The experimental group was superior to the control group in improving MCV after treatment(P<0.05). In terms of average blood glucose change, there is no statistical significance of the improvement of average blood glucose between experimental group and the control group(MD=-0.15, 95%CI[-0.82, 0.51], P=0.65). In terms of overall response rate, the curative effect of the experimental group in the treatment of DPN was superior to that of the control group(RR=1.23, 95%CI[1.11, 1.37], P=0.000 1). In terms of adverse events, no obvious adverse events were reported in the included RCTs. In light of existing data and indexes, the clinical efficacy of Shuxuetong Injection combined with western medicine in the treatment of DPN may be superior to that of conventional western medicine. It can improve the clinical symptoms, SCV, MCV, and average blood glucose of DPN, with good safety. However, existing clinical trials are few and the quality is low. It is recommended to further verify the above conclusions with internationally recognized outcome indicators.


Asunto(s)
Diabetes Mellitus , Neuropatías Diabéticas , Medicamentos Herbarios Chinos , Humanos , Glucemia , Diabetes Mellitus/tratamiento farmacológico , Neuropatías Diabéticas/tratamiento farmacológico , Medicamentos Herbarios Chinos/efectos adversos
14.
Zhongguo Zhong Yao Za Zhi ; 47(6): 1700-1704, 2022 Mar.
Artículo en Zh | MEDLINE | ID: mdl-35347970

RESUMEN

The "triple combination" review system provides an opportunity for the transformation of human use experience into new Chinese drugs. However, there are some methodological and technical limitations in the assessment of human experience. Hence, the efficacy and safety evaluation methods should be established in accordance with the characteristics of Chinese herbs. This study summarized some evidence-based methodology to promote the transformation of human use experience to new Chinese drugs, mainly including the individualized pragmatic randomized controlled trial(RCT), cluster RCT, single-case RCT, single arm RCT with objective performance criteria, and partially nested RCT. As the real world data can be used to support the transformation of human experience, attention should be paid to convenient and efficient collection of data, prudent selection of design types, and adoption of appropriate ana-lysis methods to deal with confounding bias, including multi-factor regression model and propensity score. The newly proposed mixed research method can also be utilized to assess the human use experience, which is suitable for mining the theory of traditional Chinese medicine(TCM) and expert experience from different aspects. Meanwhile, considering the study design requirements and TCM cha-racteristics, this study put forward the common problems and solutions in the development of new Chinese drugs based on human use experience, including how to select the feasible outcome indicators, how to collect prescription data in the case of herb and dosage adjustment, and how to evaluate the comprehensive effectiveness of TCM from the perspective of "combination of disease and syndrome".


Asunto(s)
Medicamentos Herbarios Chinos , China , Desarrollo de Medicamentos , Medicamentos Herbarios Chinos/uso terapéutico , Humanos , Medicina Tradicional China , Proyectos de Investigación
15.
Zhongguo Zhong Yao Za Zhi ; 47(1): 259-264, 2022 Jan.
Artículo en Zh | MEDLINE | ID: mdl-35178932

RESUMEN

Since narrative medicine was introduced in China, it has been widely used in medical education and clinical practice. The research on narrative medicine in China is especially characterized by its combination with traditional Chinese medicine(TCM). At present, the research on narrative medicine in China is still in the stage of small-scale practicing and theory advocating. Besides, there is also a lack of guidance on experimental design methodology for clinical application, which leads to few high-quality studies in this field. The present study reviewed the current high-quality research on narrative medicine to discuss the value and prospects of mixed methods research in narrative medicine. In addition, the common design, application procedures, and notes of mixed methods research were explained to provide references for the extensive applications of narrative medicine in the medical field, especially TCM clinical practice, education, and scientific research.


Asunto(s)
Medicamentos Herbarios Chinos , Medicina Narrativa , China , Medicina Tradicional China , Proyectos de Investigación
16.
Chembiochem ; 22(15): 2535-2539, 2021 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-32789938

RESUMEN

Tyrosine plays important roles in many enzymes. To facilitate enzyme design, mechanistic studies and minimize structural perturbation in the active site, here we report the genetic incorporation of a novel unnatural amino acid selenotyrosine (SeHF), which has single-atom replacement in comparison to tyrosine. The arPTE-(Agrobacterium radiobacter Phosphotriesterase) Tyr309SeHF mutant exhibits a significant 12-fold increase in kcat and 3.2-fold enhancement in kcat /KM at pH 7.0. Molecular dynamics simulations show that the SeHF309 mutation results in a conformational switch which opens up the product release pocket and increases the product release rate, thereby elevating the overall enzyme activity. Significant improvement of the catalytic efficiency at neutral pH by single unnatural amino acid (UAA) mutation broadens the application of this enzyme, and provides valuable insights to the mechanism. Our method represents a new approach for designing enzymes with enhanced activity.


Asunto(s)
Hidrolasas de Triéster Fosfórico , Agrobacterium tumefaciens
17.
FASEB J ; 34(2): 2252-2268, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31908010

RESUMEN

The myometrium undergoes structural and functional remodeling during pregnancy. We hypothesize that myometrial genomic elements alter correspondingly in preparation for parturition. Human myometrial tissues from nonpregnant (NP) and term pregnant (TP) human subjects were examined by RNAseq, ATACseq, and PGR ChIPseq assays to profile transcriptome, assessible genome, and PGR occupancy. NP and TP specimens exhibit 2890 differentially expressed genes, reflecting an increase of metabolic, inflammatory, and PDGF signaling, among others, in adaptation to pregnancy. At the epigenome level, patterns of accessible genome change between NP and TP myometrium, leading to the altered enrichment of binding motifs for hormone and muscle regulators such as the progesterone receptor (PGR), Krüppel-like factors, and MEF2A transcription factors. PGR genome occupancy exhibits a significant difference between the two stages of the myometrium, concomitant with distinct transcriptomic profiles including genes such as ENO1, LHDA, and PLCL1 in the glycolytic and calcium signaling pathways. Over-representation of SRF, MYOD, and STAT binding motifs in PGR occupying sites further suggests interactions between PGR and major muscle regulators for myometrial gene expression. In conclusion, changes in accessible genome and PGR occupancy are part of the myometrial remodeling process and may serve as mechanisms to formulate the state-specific transcriptome profiles.


Asunto(s)
Genoma Humano , Proteínas Musculares/biosíntesis , Miometrio/metabolismo , Proteínas Gestacionales/biosíntesis , Embarazo/metabolismo , RNA-Seq , Transcriptoma , Adulto , Femenino , Humanos , Proteínas Musculares/genética , Proteínas Gestacionales/genética
18.
PLoS Biol ; 16(4): e2005707, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29668680

RESUMEN

Mitochondrial function affects many aspects of cellular physiology, and, most recently, its role in epigenetics has been reported. Mechanistically, how mitochondrial function alters DNA methylation patterns in the nucleus remains ill defined. Using a cell culture model of induced mitochondrial DNA (mtDNA) depletion, in this study we show that progressive mitochondrial dysfunction leads to an early transcriptional and metabolic program centered on the metabolism of various amino acids, including those involved in the methionine cycle. We find that this program also increases DNA methylation, which occurs primarily in the genes that are differentially expressed. Maintenance of mitochondrial nicotinamide adenine dinucleotide reduced (NADH) oxidation in the context of mtDNA loss rescues methionine salvage and polyamine synthesis and prevents changes in DNA methylation and gene expression but does not affect serine/folate metabolism or transsulfuration. This work provides a novel mechanistic link between mitochondrial function and epigenetic regulation of gene expression that involves polyamine and methionine metabolism responding to changes in the tricarboxylic acid (TCA) cycle. Given the implications of these findings, future studies across different physiological contexts and in vivo are warranted.


Asunto(s)
Núcleo Celular/metabolismo , Ciclo del Ácido Cítrico/genética , Metilación de ADN , ADN Mitocondrial/genética , Metionina/metabolismo , Mitocondrias/genética , NAD/metabolismo , Línea Celular Tumoral , Núcleo Celular/genética , ADN Mitocondrial/metabolismo , Epigénesis Genética , Ácido Fólico/metabolismo , Células HEK293 , Humanos , Mitocondrias/metabolismo , Osteoblastos/citología , Osteoblastos/metabolismo , Oxidación-Reducción , Serina/metabolismo , Ácidos Tricarboxílicos/metabolismo
19.
PLoS Genet ; 14(11): e1007787, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30452456

RESUMEN

Successful embryo implantation requires a receptive endometrium. Poor uterine receptivity can account for implantation failure in women who experience recurrent pregnancy loss or multiple rounds of unsuccessful in vitro fertilization cycles. Here, we demonstrate that the transcription factor Forkhead Box O1 (FOXO1) is a critical regulator of endometrial receptivity in vivo. Uterine ablation of Foxo1 using the progesterone receptor Cre (PgrCre) mouse model resulted in infertility due to altered epithelial cell polarity and apoptosis, preventing the embryo from penetrating the luminal epithelium. Analysis of the uterine transcriptome after Foxo1 ablation identified alterations in gene expression for transcripts involved in the activation of cell invasion, molecular transport, apoptosis, ß-catenin (CTNNB1) signaling pathway, and an increase in PGR signaling. The increase of PGR signaling was due to PGR expression being retained in the uterine epithelium during the window of receptivity. Constitutive expression of epithelial PGR during this receptive period inhibited expression of FOXO1 in the nucleus of the uterine epithelium. The reciprocal expression of PGR and FOXO1 was conserved in human endometrial samples during the proliferative and secretory phase. This demonstrates that expression of FOXO1 and the loss of PGR during the window of receptivity are interrelated and critical for embryo implantation.


Asunto(s)
Implantación del Embrión/genética , Implantación del Embrión/fisiología , Endometrio/metabolismo , Proteína Forkhead Box O1/genética , Proteína Forkhead Box O1/metabolismo , Receptores de Progesterona/genética , Receptores de Progesterona/metabolismo , Animales , Núcleo Celular/metabolismo , Polaridad Celular/genética , Polaridad Celular/fisiología , Decidua/fisiología , Endometrio/citología , Femenino , Proteína Forkhead Box O1/deficiencia , Perfilación de la Expresión Génica , Humanos , Ratones , Ratones Noqueados , Embarazo , Receptores de Progesterona/deficiencia , Transducción de Señal
20.
Proc Natl Acad Sci U S A ; 115(18): E4189-E4198, 2018 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-29666266

RESUMEN

Early transient developmental exposure to an endocrine active compound, diethylstilbestrol (DES), a synthetic estrogen, causes late-stage effects in the reproductive tract of adult mice. Estrogen receptor alpha (ERα) plays a role in mediating these developmental effects. However, the developmental mechanism is not well known in male tissues. Here, we present genome-wide transcriptome and DNA methylation profiling of the seminal vesicles (SVs) during normal development and after DES exposure. ERα mediates aberrations of the mRNA transcriptome in SVs of adult mice following neonatal DES exposure. This developmental exposure impacts differential diseases between male (SVs) and female (uterus) tissues when mice reach adulthood due to most DES-altered genes that appear to be tissue specific during mouse development. Certain estrogen-responsive gene changes in SVs are cell-type specific. DNA methylation dynamically changes during development in the SVs of wild-type (WT) and ERα-knockout (αERKO) mice, which increases both the loss and gain of differentially methylated regions (DMRs). There are more gains of DMRs in αERKO compared with WT. Interestingly, the methylation changes between the two genotypes are in different genomic loci. Additionally, the expression levels of a subset of DES-altered genes are associated with their DNA methylation status following developmental DES exposure. Taken together, these findings provide an important basis for understanding the molecular and cellular mechanism of endocrine-disrupting chemicals (EDCs), such as DES, during development in the male mouse tissues. This unique evidence contributes to our understanding of developmental actions of EDCs in human health.


Asunto(s)
Metilación de ADN/efectos de los fármacos , Dietilestilbestrol/efectos adversos , Receptor alfa de Estrógeno/metabolismo , Estrógenos no Esteroides/efectos adversos , Regulación de la Expresión Génica/efectos de los fármacos , Vesículas Seminales/metabolismo , Transcriptoma/efectos de los fármacos , Animales , Metilación de ADN/genética , Dietilestilbestrol/farmacología , Receptor alfa de Estrógeno/agonistas , Receptor alfa de Estrógeno/genética , Estrógenos no Esteroides/farmacología , Sitios Genéticos , Masculino , Ratones , Ratones Noqueados
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