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1.
Plant Biotechnol J ; 22(11): 3121-3134, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39021281

RESUMEN

Cis-regulatory elements (CREs) are integral to the spatiotemporal and quantitative expression dynamics of target genes, thus directly influencing phenotypic variation and evolution. However, many of these CREs become highly susceptible to transcriptional silencing when in a transgenic state, particularly when organised as tandem repeats. We investigated the mechanism of this phenomenon and found that three of the six selected flower-specific CREs were prone to transcriptional silencing when in a transgenic context. We determined that this silencing was caused by the ectopic expression of non-coding RNAs (ncRNAs), which were processed into 24-nt small interfering RNAs (siRNAs) that drove RNA-directed DNA methylation (RdDM). Detailed analyses revealed that aberrant ncRNA transcription within the AGAMOUS enhancer (AGe) in a transgenic context was significantly enhanced by an adjacent CaMV35S enhancer (35Se). This particular enhancer is known to mis-activate the regulatory activities of various CREs, including the AGe. Furthermore, an insertion of 35Se approximately 3.5 kb upstream of the AGe in its genomic locus also resulted in the ectopic induction of ncRNA/siRNA production and de novo methylation specifically in the AGe, but not other regions, as well as the production of mutant flowers. This confirmed that interactions between the 35Se and AGe can induce RdDM activity in both genomic and transgenic states. These findings highlight a novel epigenetic role for CRE-CRE interactions in plants, shedding light on the underlying forces driving hypermethylation in transgenes, duplicate genes/enhancers, and repetitive transposons, in which interactions between CREs are inevitable.


Asunto(s)
Metilación de ADN , Elementos de Facilitación Genéticos , Regulación de la Expresión Génica de las Plantas , Plantas Modificadas Genéticamente , ARN no Traducido , Metilación de ADN/genética , Elementos de Facilitación Genéticos/genética , Plantas Modificadas Genéticamente/genética , ARN no Traducido/genética , ARN no Traducido/metabolismo , Silenciador del Gen , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , ARN de Planta/genética , ARN de Planta/metabolismo , Flores/genética , Arabidopsis/genética
2.
J Biochem Mol Toxicol ; 36(7): e23049, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35307913

RESUMEN

Chinese herbal medicine has well-established therapeutic effects in various diseases. Corilagin (Cor), a gallic acid tannin in Phyllanthus niruri L., has anti-inflammatory and antioxidant effects in many diseases. However, its role in osteoclast-related bone diseases has not been determined. In vitro, bone marrow macrophages (BMMs) were extracted and isolated to differentiate into osteoclasts. The effects of Cor on osteoclast formation, bone resorption, and reactive oxygen species (ROS) production were performed. In addition, quantitative real-time polymerase chain reaction and western blot analysis were used to evaluate the effect of Cor on oxidative stress-related pathways, which are nuclear factors-κB ligand-receptor activator (RANKL) stimulates important downstream pathways. Furthermore, microcomputed tomography and bone histomorphometry were performed to analyze the therapeutic effect of Cor in mouse models of lipopolysaccharide (LPS)-mediated bone defects in vivo. Cor influenced the nuclear factor of activated T cells 1 (NFATc1) signaling pathway and reduced ROS in RANKL-treated osteoclasts, thereby inhibiting osteoclast formation and bone resorption. Moreover, Cor protected against LPS-mediated skull defects in vivo. In sum, our results confirm that Cor can inhibit osteoclastogenesis and intracellular oxidative stress. In addition, the inflammatory bone defect induced by LPS was also attenuated by Cor. Accordingly, Cor is a new candidate therapeutic agent for osteoclast-mediated osteolytic diseases.


Asunto(s)
Osteoclastos , Osteólisis , Animales , Diferenciación Celular , Glucósidos , Taninos Hidrolizables , Lipopolisacáridos/farmacología , Ratones , Ratones Endogámicos C57BL , Osteoclastos/metabolismo , Osteogénesis , Osteólisis/inducido químicamente , Osteólisis/tratamiento farmacológico , Osteólisis/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Microtomografía por Rayos X
3.
J Nanobiotechnology ; 20(1): 38, 2022 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-35057811

RESUMEN

Osteoarthritis (OA) is a degenerative illness that greatly impacts the life quality of patients. Currently, the therapeutic approaches for OA are very limited in clinical. The extracellular vesicles (EVs) derived from different mesenchymal stem cells displayed a prominent therapeutic effect on OA. But most EVs have limited resources and the risks of host rejection, immunological response, and etc. Human umbilical cord mesenchymal stem cells (hUCMSCs) hold the advantages of easy availability, minimal immune rejection, and excellent immunomodulatory effects, although hUCMSCs-EVs have seldom been applied in OA. Herein, we investigated the potential immunomodulatory and anti-inflammatory effects of hUCMSCs-EVs on the treatment of OA. In our results, the treatment of hUCMSCs-EVs promoted the polarization of M2-type macrophages and the expression of anti-inflammation-related cytokines (IL-10). Notably, the supernate of M2 macrophages induced by hUCMSCs-EVs inhibited the level of inflammation-associated factors in OA chondrocytes caused by IL-1ß. Further, injection of hUCMSCs-EVs in the articular lumen ameliorated progression of OA and exerted chondroprotective potential based on the OA joint model created by the surgical transection of the anterior cruciate ligament (ACLT). In addition, we found five highly enriched miRNAs in hUCMSCs-EVs, including has-miR-122-5p, has-miR-148a-3p, has-miR-486-5p, has-miR-let-7a-5p, and has-miR-100-5p by High-throughput sequencing of miRNAs, with targeted genes mainly enriched in the PI3K-Akt signaling pathway. Furthermore, we also detected the protein abundance of hUCMSCs-EVs using liquidation chromatography with tandem quadrupole mass spectrometry (LC-MS/MS) analysis. Thus, our study indicates that hUCMSCs-EVs can alleviate cartilage degradation during the OA progression, mechanically may through delivering key proteins and modulating the PI3K-Akt signaling pathway mediated by miRNAs to promote polarization of M2 macrophage, exhibiting potent immunomodulatory potential. The current findings suggest that hUCMSCs-EVs might serve as a new reagent for the therapy of OA.


Asunto(s)
Antiinflamatorios , Vesículas Extracelulares/química , Células Madre Mesenquimatosas/citología , Osteoartritis/metabolismo , Cordón Umbilical/citología , Animales , Antiinflamatorios/química , Antiinflamatorios/farmacología , Extractos Celulares/química , Extractos Celulares/farmacología , Humanos , Agentes Inmunomoduladores/química , Agentes Inmunomoduladores/farmacología , Macrófagos/efectos de los fármacos , Masculino , Ratas , Ratas Sprague-Dawley
4.
Entropy (Basel) ; 24(10)2022 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-37420492

RESUMEN

Numerous methods have been developed for longitudinal binomial data in the literature. These traditional methods are reasonable for longitudinal binomial data with a negative association between the number of successes and the number of failures over time; however, a positive association may occur between the number of successes and the number of failures over time in some behaviour, economic, disease aggregation and toxicological studies as the numbers of trials are often random. In this paper, we propose a joint Poisson mixed modelling approach to longitudinal binomial data with a positive association between longitudinal counts of successes and longitudinal counts of failures. This approach can accommodate both a random and zero number of trials. It can also accommodate overdispersion and zero inflation in the number of successes and the number of failures. An optimal estimation method for our model has been developed using the orthodox best linear unbiased predictors. Our approach not only provides robust inference against misspecified random effects distributions, but also consolidates the subject-specific and population-averaged inferences. The usefulness of our approach is illustrated with an analysis of quarterly bivariate count data of stock daily limit-ups and limit-downs.

5.
Plant Physiol ; 184(4): 1702-1716, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33037127

RESUMEN

Recent studies have shown that loss of pollen-S function in S4' pollen from sweet cherry (Prunus avium) is associated with a mutation in an S haplotype-specific F-box4 (SFB4) gene. However, how this mutation leads to self-compatibility is unclear. Here, we examined this mechanism by analyzing several self-compatible sweet cherry varieties. We determined that mutated SFB4 (SFB4') in S4' pollen (pollen harboring the SFB4' gene) is approximately 6 kD shorter than wild-type SFB4 due to a premature termination caused by a four-nucleotide deletion. SFB4' did not interact with S-RNase. However, a protein in S4' pollen ubiquitinated S-RNase, resulting in its degradation via the 26S proteasome pathway, indicating that factors in S4' pollen other than SFB4 participate in S-RNase recognition and degradation. To identify these factors, we used S4-RNase as a bait to screen S4' pollen proteins. Our screen identified the protein encoded by S 4 -SLFL2, a low-polymorphic gene that is closely linked to the S-locus. Further investigations indicate that SLFL2 ubiquitinates S-RNase, leading to its degradation. Subcellular localization analysis showed that SFB4 is primarily localized to the pollen tube tip, whereas SLFL2 is not. When S 4 -SLFL2 expression was suppressed by antisense oligonucleotide treatment in wild-type pollen tubes, pollen still had the capacity to ubiquitinate S-RNase; however, this ubiquitin-labeled S-RNase was not degraded via the 26S proteasome pathway, suggesting that SFB4 does not participate in the degradation of S-RNase. When SFB4 loses its function, S4-SLFL2 might mediate the ubiquitination and degradation of S-RNase, which is consistent with the self-compatibility of S4' pollen.


Asunto(s)
Polinización/genética , Polinización/fisiología , Prunus avium/genética , Prunus avium/fisiología , Ribonucleasas/genética , Ribonucleasas/fisiología , Ubiquitinación/genética , Ubiquitinación/fisiología , China , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Variación Genética , Genotipo , Mutación
6.
J Nanobiotechnology ; 18(1): 163, 2020 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-33167997

RESUMEN

BACKGROUND: Umbilical cord mesenchymal stem cell (HUCMSC)-based therapies were previously utilised for cartilage regeneration because of the chondrogenic potential of MSCs. However, chondrogenic differentiation of HUCMSCs is limited by the administration of growth factors like TGF-ß that may cause cartilage hypertrophy. It has been reported that extracellular vesicles (EVs) could modulate the phenotypic expression of stem cells. However, the role of human chondrogenic-derived EVs (C-EVs) in chondrogenic differentiation of HUCMSCs has not been reported. RESULTS: We successfully isolated C-EVs from human multi-finger cartilage and found that C-EVs efficiently promoted the proliferation and chondrogenic differentiation of HUCMSCs, evidenced by highly expressed aggrecan (ACAN), COL2A, and SOX-9. Moreover, the expression of the fibrotic marker COL1A and hypertrophic marker COL10 was significantly lower than that induced by TGF-ß. In vivo, C-EVs induced HUCMSCs accelerated the repair of the rabbit model of knee cartilage defect. Furthermore, C-EVs led to an increase in autophagosomes during the process of chondrogenic differentiation, indicating that C-EVs promote cartilage regeneration through the activation of autophagy. CONCLUSIONS: C-EVs play an essential role in fostering chondrogenic differentiation and proliferation of HUCMSCs, which may be beneficial for articular cartilage repair.


Asunto(s)
Autofagia/fisiología , Cartílago/metabolismo , Condrocitos/metabolismo , Vesículas Extracelulares/metabolismo , Células Madre Mesenquimatosas/metabolismo , Cordón Umbilical/metabolismo , Animales , Diferenciación Celular , Proliferación Celular , Células Cultivadas , Condrocitos/citología , Condrogénesis , Femenino , Humanos , Masculino , Células Madre Mesenquimatosas/citología , Conejos , Cordón Umbilical/citología
7.
Stat Med ; 37(24): 3519-3532, 2018 10 30.
Artículo en Inglés | MEDLINE | ID: mdl-29888505

RESUMEN

Generalized linear mixed models have played an important role in the analysis of longitudinal data; however, traditional approaches have limited flexibility in accommodating skewness and complex correlation structures. In addition, the existing estimation approaches generally rely heavily on the specifications of random effects distributions; therefore, the corresponding inferences are sometimes sensitive to the choice of random effect distributions under certain circumstance. In this paper, we incorporate serially dependent distribution-free random effects into Tweedie generalized linear models to accommodate a wide range of skewness and covariance structures for discrete and continuous longitudinal data. An optimal estimation of our model has been developed using the orthodox best linear unbiased predictors of random effects. Our approach unifies population-averaged and subject-specific inferences. Our method is illustrated through the analyses of patient-controlled analgesia data and Framingham cholesterol data.


Asunto(s)
Modelos Lineales , Estudios Longitudinales , Analgesia Controlada por el Paciente/estadística & datos numéricos , Bioestadística , Enfermedades Cardiovasculares/sangre , Enfermedades Cardiovasculares/epidemiología , Colesterol/sangre , Simulación por Computador , Interpretación Estadística de Datos , Humanos , Funciones de Verosimilitud , Factores de Riesgo
8.
Plant Biotechnol J ; 14(11): 2120-2133, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27107393

RESUMEN

Sweet cherry is a diploid tree species and its fruit skin has rich colours from yellow to blush to dark red. The colour is closely related to anthocyanin biosynthesis and is mainly regulated at the transcriptional level by transcription factors that regulate the expression of multiple structural genes. However, the genetic and molecular bases of how these genes ultimately determine the fruit skin colour traits remain poorly understood. Here, our genetic and molecular evidences identified the R2R3 MYB transcription factor PavMYB10.1 that is involved in anthocyanin biosynthesis pathway and determines fruit skin colour in sweet cherry. Interestingly, we identified three functional alleles of the gene causally leading to the different colours at mature stage. Meanwhile, our experimental results of yeast two-hybrid assays and chromatin immunoprecipitation assays revealed that PavMYB10.1 might interact with proteins PavbHLH and PavWD40, and bind to the promoter regions of the anthocyanin biosynthesis genes PavANS and PavUFGT; these findings provided to a certain extent mechanistic insight into the gene's functions. Additionally, genetic and molecular evidences confirmed that PavMYB10.1 is a reliable DNA molecular marker to select fruit skin colour in sweet cherry.


Asunto(s)
Antocianinas/genética , Frutas/genética , Pigmentación/genética , Prunus avium/genética , Factores de Transcripción/metabolismo , Antocianinas/metabolismo , Frutas/metabolismo , Regulación de la Expresión Génica de las Plantas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/metabolismo , Prunus avium/metabolismo , Factores de Transcripción/genética
9.
J Med Virol ; 88(6): 1018-26, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26531675

RESUMEN

Evolution patterns of HBV QS between genotype B and C during vertical transmission are not well understood. In this study, we enrolled 10 HBV infected mother-infant pairs (four pairs with genotype B, four pairs with genotype C, and two with co-infection) without anti-viral therapy. Serum HBV DNA of mothers and infants were sequenced, HBV QS complexity and diversity were analyzed, polymorphisms and mutation sites were recorded, and phylogenetic trees were performed. Our result showed that the QS complexities in P (amino acid), C/PreC (amino acid), and PreS1 (nucleotide) gene were significantly higher in mothers than in infants in pairs with genotype C (P < 0.05), however, full-length and other genes showed non-significant differences (P > 0.05). Unlike genotype C, QS complexity of P gene (nucleotide) was significantly higher in infants than in mothers (P < 0.05) in pairs with genotype B, similarly, QS complexities of full-length and other genes (except Pre S2) were also higher in infants than in mothers but without significant differences (P > 0.05). QS diversities of full-length and most genes in genotype B were comparable between mothers and their infants (P > 0.05), in pairs with genotype C, dS of P, X, RT genes, genetic distance of Pre S1 gene (amino acid) and dN of Pre S1 gene were significant higher in mothers than in infants (P < 0.05). Several HBV mutations correlated with immune escape, e antigen loss and drug resistance were observed in infants. The results indicated that differences of HBV QS evolution patterns between genotype B and C during vertical transmission might contribute to distinct prognosis.


Asunto(s)
Evolución Molecular , Virus de la Hepatitis B/genética , Hepatitis B Crónica/transmisión , Hepatitis B/transmisión , Transmisión Vertical de Enfermedad Infecciosa , Mutación , Adulto , Coinfección , ADN Viral/sangre , Farmacorresistencia Viral/genética , Femenino , Genotipo , Hepatitis B/virología , Antígenos de Superficie de la Hepatitis B/genética , Antígenos e de la Hepatitis B/genética , Hepatitis B Crónica/virología , Humanos , Evasión Inmune/genética , Lactante , Madres , Filogenia , Reacción en Cadena de la Polimerasa , Polimorfismo Genético , Precursores de Proteínas/genética , Análisis de Secuencia de ADN , Adulto Joven
10.
Ecology ; 96(11): 3023-32, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27070021

RESUMEN

Disturbance plays a key role in driving ecological responses by creating opportunities for new ecological communities to assemble and by directly influencing the outcomes of assembly. Legacy effects (such as seed banks) and environmental filters can both influence community assembly, but their effects are impossible to separate with observational data. Here, we used seeding experiments in sites covering a broad range of postdisturbance conditions to tease apart the effects of seed availability, environmental factors, and disturbance characteristics on early community assembly after fire. We added seed of four common boreal trees to experimental plots in 55 replicate sites in recently burned areas of black spruce forest in northwestern North America. Seed addition treatments increased the probability of occurrence for all species, indicating a widespread potential for seed limitation to affect patterns of recruitment after fire. Small-seeded. species (aspen and birch) were most sensitive to environmental factors such as soil moisture and organic layer depth, suggesting a role for niche-based environmental filtering in community assembly. Fire characteristics related to severity and frequency were also important drivers of seedling regeneration, indicating the potential for disturbance to mediate environmental filters and legacy effects on seed availability. Because effects of seed availability are typically impossible to disentangle from environmental constraints on recruitment in observational studies, legacy effects contingent on vegetation history may be misinterpreted as being driven by strong environmental filters. Results from the seeding experiments suggest that vegetation legacies affecting seed availability play a pivotal role in shaping patterns of community assembly after fire in these low-diversity boreal forests.


Asunto(s)
Incendios , Taiga , Árboles/fisiología , Alaska , Monitoreo del Ambiente , Dinámica Poblacional , Plantones , Semillas , Suelo , Factores de Tiempo , Árboles/clasificación , El Yukón
11.
Liver Int ; 35(8): 1941-9, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25469587

RESUMEN

BACKGROUND & AIMS: The toll-like receptor-interferon (TLR-IFN) signalling pathway plays a crucial role in HBV infection. Human leucocyte antigen (HLA) polymorphisms are associated with chronic HBV infection by genome wide association study (GWAS). We aimed to explore interaction between TLR-IFN and HLA gene polymorphisms in susceptibility of chronic HBV infection. METHODS: In the Chinese Southwest Han population, 1191 chronic HBV infection patients and 273 HBV clearance were selected. A total of 39 single nucleotide polymorphism loci in 23 genes of the TLR-IFN pathway and four HLA polymorphism loci associated with chronic HBV infection identified by GWAS were selected for genotyping. SNPStats, QVALUE, and multifactor dimensionality reduction were used for statistical analysis. RESULTS: A significant association was seen in several of the TLR-IFN pathway genes, TLR9 rs352140 (OR = 0.70, P = 0.0088), IL1B rs16944 (OR = 0.67, P = 0.016), IL12B rs3212227 (OR = 1.38, P = 0.021), IFNGR1 rs3799488 (OR = 1.48, P = 0.0048), IFNGR2 rs1059293 (OR = 0.27, P = 0.011), MX1 rs467960 (OR = 0.68, P = 0.022), as well as four loci in HLA, rs3077 (OR = 0.55, P < 0.0001), rs2856718 (OR = 0.60, P = 4e-04), rs9277535 (OR = 0.54, P < 0.0001) and rs7453920 (OR = 0.43, P < 0.0001). A synergistic relationship was seen between rs9277535 and rs16944 (0.13%), rs1143623 and rs6613 (0.10%). The combination of rs9277535 in HLA and rs16944 in IL1B was the best model to predict chronic HBV infection (testing accuracy = 0.6040, P = 0.0010, cross-validation consistency = 10/10). CONCLUSIONS: TLR-IFN pathway gene polymorphisms are associated with chronic HBV infection. Interactions with polymorphisms in these genes may be one mechanism by which HLA polymorphisms influence susceptibility to chronic HBV infection, as specific single nucleotide polymorphism combinations are highly predictive of chronic HBV infection.


Asunto(s)
Predisposición Genética a la Enfermedad/epidemiología , Hepatitis B Crónica/etnología , Hepatitis B Crónica/genética , Receptores de Interferón/genética , Receptores Toll-Like/genética , Adulto , Pueblo Asiatico/genética , Estudios de Casos y Controles , China/epidemiología , Femenino , Estudio de Asociación del Genoma Completo , Antígenos HLA/genética , Haplotipos/genética , Virus de la Hepatitis B/genética , Hepatitis B Crónica/fisiopatología , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Polimorfismo de Nucleótido Simple
12.
Planta ; 239(2): 469-78, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24221021

RESUMEN

The genetic engineering of agronomic traits requires an array of highly specific and tightly regulated promoters that drive expression in floral tissues. In this study, we isolated and characterized two tobacco APETALA1-like (AP1-like) promoters (termed NtAP1La and NtAP1Lb1) in transgenic plants using the GUS reporter system, along with tissue-specific ablation analyses. Our results demonstrated that the two promoters are active in floral inflorescences but not in vegetative apical meristems or other vegetative tissues, as reflected by strong GUS staining and DT-A-mediated ablation of apical shoot tips during reproductive but not vegetative growth. We also showed that the NtAP1Lb1 promoter was more active than NtAP1La in inflorescences, as the former yielded higher frequencies and greater phenotypic evidence of tissue ablation compared to the latter. We further revealed that both promoters were uniformly expressed in the meristems of stage 1 and 2 floral buds, but were differentially expressed in floral organs later during development. While NtAP1La was found to be active in stage 4-5 carpels, later becoming confined to ovary tissue from stage 9 onwards, NtAP1Lb1 activity was apparent in all floral organs from stages 3 to 7, becoming completely absent in all floral organs from stage 11 onward. Therefore, it seems that the two tobacco promoters have acquired similar but distinct inflorescence-, floral meristem- and floral organ-specific and development-dependent regulatory features without any leaky activity in vegetative tissues. These features are novel and have rarely been observed in other flower-specific promoters characterized to date. The potential application of these promoters for engineering sterility, increasing biomass production and modifying flower architecture, as well as their putative use in flower-specific transgene excision, will be discussed.


Asunto(s)
Flores/genética , Regulación del Desarrollo de la Expresión Génica , Nicotiana/genética , Proteínas de Plantas/genética , Regiones Promotoras Genéticas/genética , Secuencia de Bases , Sitios de Unión , Biología Computacional , Cartilla de ADN/genética , Flores/citología , Flores/crecimiento & desarrollo , Regulación de la Expresión Génica de las Plantas , Genes Reporteros , Inflorescencia/citología , Inflorescencia/genética , Inflorescencia/crecimiento & desarrollo , Meristema/citología , Meristema/genética , Meristema/crecimiento & desarrollo , Datos de Secuencia Molecular , Especificidad de Órganos , Plantas Modificadas Genéticamente , Análisis de Secuencia de ADN , Nicotiana/citología , Nicotiana/crecimiento & desarrollo
13.
Plant Biotechnol J ; 12(7): 951-62, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24893677

RESUMEN

Molecular stacking enables multiple traits to be effectively engineered in crops using a single vector. However, the co-existence of distinct plant promoters in the same transgenic unit might, like their mammalian counterparts, interfere with one another. In this study, we devised a novel approach to investigate enhancer-promoter and promoter-promoter interactions in transgenic plants and demonstrated that three of four flower-specific enhancer/promoters were capable of distantly activating a pollen- and stigma-specific Pps promoter (fused to the cytotoxic DT-A gene) in other tissues, as revealed by novel tissue ablation phenotypes in transgenic plants. The NtAGI1 enhancer exclusively activated stamen- and carpel-specific DT-A expression, thus resulting in tissue ablation in an orientation-independent manner; this activation was completely abolished by the insertion of an enhancer-blocking insulator (EXOB) between the NtAGI1 enhancer and Pps promoter. Similarly, AGL8 and AP1Lb1, but not AP1La, promoters also activated distinct tissue-specific DT-A expression and ablation, with the former causing global growth retardation and the latter ablating apical inflorescences. While the tissue specificity of the enhancer/promoters generally defined their activation specificities, the strength of their activity in particular tissues or developmental stages appeared to determine whether activation actually occurred. Our findings provide the first evidence that plant-derived enhancer/promoters can distantly interact/interfere with one another, which could pose potential problems for the tissue-specific engineering of multiple traits using a single-vector stacking approach. Therefore, our work highlights the importance of adopting enhancer-blocking insulators in transformation vectors to minimize promoter-promoter interactions. The practical and fundamental significance of these findings will be discussed.


Asunto(s)
Elementos de Facilitación Genéticos/fisiología , Nicotiana/genética , Plantas Modificadas Genéticamente/metabolismo , Regiones Promotoras Genéticas/fisiología , Flores/genética , Flores/crecimiento & desarrollo , Flores/metabolismo , Regulación de la Expresión Génica de las Plantas , Ingeniería Genética/métodos , Vectores Genéticos , Plantas Modificadas Genéticamente/genética , Nicotiana/crecimiento & desarrollo , Nicotiana/metabolismo , Transformación Genética , Transgenes
14.
Rev Biol Trop ; 62(4): 1637-48, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25720193

RESUMEN

Eichhornia crassipes is an aquatic plant native to the Amazon River Basin. It has become a serious weed in freshwater habitats in rivers, lakes and reservoirs both in tropical and warm temperate areas worldwide. Some research has stated that it can be used for water phytoremediation, due to its strong assimilation of nitrogen and phosphorus, and the accumulation of heavy metals, and its growth and spread may play an important role in environmental ecology. In order to explore the molecular mechanism of E. crassipes to responses to nitrogen deficiency, we constructed forward and reversed subtracted cDNA libraries for E. crassipes roots under nitrogen deficient condition using a suppressive subtractive hybridization (SSH) method. The forward subtraction included 2,100 clones, and the reversed included 2,650 clones. One thousand clones were randomly selected from each library for sequencing. About 737 (527 unigenes) clones from the forward library and 757 (483 unigenes) clones from the reversed library were informative. Sequence BlastX analysis showed that there were more transporters and adenosylhomocysteinase-like proteins in E. crassipes cultured in nitrogen deficient medium; while, those cultured in nitrogen replete medium had more proteins such as UBR4-like e3 ubiquitin-protein ligase and fasciclin-like arabinogalactan protein 8-like, as well as more cytoskeletal proteins, including actin and tubulin. Cluster of Orthologous Group (COG) analysis also demonstrated that in the forward library, the most ESTs were involved in coenzyme transportation and metabolism. In the reversed library, cytoskeletal ESTs were the most abundant. Gene Ontology (GO) analysis categories demonstrated that unigenes involved in binding, cellular process and electron carrier were the most differentially expressed unigenes between the forward and reversed libraries. All these results suggest that E. crassipes can respond to different nitrogen status by efficiently regulating and controlling some transporter gene expressions, certain metabolism processes, specific signal transduction pathways and cytoskeletal construction.


Asunto(s)
Eichhornia/genética , Restauración y Remediación Ambiental , Etiquetas de Secuencia Expresada , Genes de Plantas , Nitrógeno/metabolismo , Fósforo/metabolismo , Eichhornia/clasificación , Eichhornia/metabolismo , Biblioteca de Genes , Nitrógeno/deficiencia , Reacción en Cadena de la Polimerasa
15.
Oncol Lett ; 28(2): 374, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38910902

RESUMEN

Circular RNAs (circRNAs) are a subclass of non-coding RNAs that are important for the regulation of gene expression in eukaryotic organisms. CircRNAs exert various regulatory roles in cancer progression. However, the role of hsa_circ_0064636 in osteosarcoma (OS) remains poorly understood. In the present study, the expression of hsa_circ_0064636 in OS cell lines was measured by reverse transcription-quantitative PCR (RT-qPCR). Differentially expressed mRNAs and microRNAs (miRNA or miRs) were screened using mRNA(GSE16088) and miRNA(GSE65071) expression datasets for OS. miRNAs that can potentially interact with hsa_circ_0064636 were predicted using RNAhybrid, TargetScan and miRanda. Subsequently, RNAhybrid, TargetScan, miRanda, miRWalk, miRMap and miRNAMap were used for target gene prediction based on the overlapping miRNAs to construct a circ/miRNA/mRNA interaction network. Target genes were subjected to survival analysis using PROGgeneV2, resulting in a circRNA/miRNA/mRNA interaction sub-network with prognostic significance. miRNA and circRNA in the subnetwork may also have survival significance, but relevant data are lacking and needs to be further proved. RT-qPCR demonstrated that hsa_circ_0064636 expression was significantly increased in OS cell lines. miR-326 and miR-503-5p were identified to be target miRNAs of hsa_circ_0064636. Among the target genes obtained from the miR-326 and miR-503-5p screens, ubiquitination factor E4A (UBE4A) and voltage dependent anion channel 1 (VDAC1) were respectively identified to significantly affect prognosis; only miR-326 targets UBE4A and only miR-503 targets VDAC1. To conclude, these aforementioned findings suggest that hsa_circ_0064636 may be involved in the development of OS by sponging miR-503-5p and miR-326to inhibit their effects, thereby regulating the expression of VDAC1 and UBE4A.

16.
Food Chem ; 463(Pt 4): 141512, 2024 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-39396431

RESUMEN

In practical sweet cherry production, grafting onto rootstocks is a common practice to enhance environmental adaptability. Rootstocks play a crucial role in influencing scion growth and fruit quality by regulating the absorption and utilization of mineral elements. In this study, the influence of five rootstocks with or without root fertilization during the fruit color conversion period on the fruit quality of sweet cherry 'Summit' was observed. The physicochemical characteristics, external color characteristics, and total anthocyanin content of 'Summit' were significantly affected by both rootstock and fertilization, with an interaction between the two factors. The content of certain sugar components, organic acid components and phenolic acid components in 'Summit' were significantly affected by rootstocks and fertilization. 'Summit' grafted on Gisela 5 and H22 exhibited higher sugar content, while 'Summit' grafted on H11 and H17 exhibited higher organic and phenolic acid content.

17.
J Clin Immunol ; 33(7): 1240-9, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23954997

RESUMEN

PURPOSE: About 60-80 % of chronic hepatitis B virus (HBV) carriers are characterized with persistently normal alanine transaminase (ALT). Differences of cytokine expression are associated with the prognosis of HBV infection. We investigated the expression pattern of 30 cytokines associated with anti-HBV immunity in patients with normal ALT. METHODS: Four patient groups (immune tolerance, inactive hepatitis B surface antigen carriers, resolved hepatitis B, and control; 10 subjects per group) were assigned. Thirty cytokines, including IFN-γ, IL-1ß, IL-2, IL-4, IL-6, IL-7, IL-9, IL-10, IL-12p40, IL-12p70, IL-15, IL-17A, IL-17C, IL-21, IL-22, IL-23p19, IL-28A, IL-29, CCL5, CCL16, CCL20, CCL22, CXCL9, CXCL10, CXCL11, TNFRSF8, TNFRSF18, IL-6R, gp130, and TGF-ß1, were measured using a human cytokine antibody array. Signal intensities were obtained by laser scanner. Protein-protein interactions were analyzed by STRING (Search Tool for the Retrieval of Interacting Genes/Proteins). RESULTS: Significant differences of signal intensities were observed for IL-2, IL-4, IL-6, IL-7, IL-9, IL-10, IL-12p40, IL-12p70, IL-15, IL-21, IL-23p19, IL-28A, and IL-29. The lowest intensity was in controls. Among three HBV infection groups, significant differences were observed in IL-2, IL-4, IL-12p70, IL-15, IL-21, IL-23p19, and IL-29. The highest intensity was in the inactive group. All cytokines with significant differences were involved JAK-STAT signaling that up-regulate FOXP3, SOCS3 and MX1. CONCLUSION: Differential expression of cytokines in JAK-STAT signaling is an important factor associated with prognosis of HBV infection. The elevation of γC cytokines, IL-12p70, IL-23p19, and IL-29 may promote spontaneous HBeAg seroconversion and HBV clearance.


Asunto(s)
Alanina Transaminasa/metabolismo , Citocinas/biosíntesis , Virus de la Hepatitis B/inmunología , Hepatitis B Crónica/diagnóstico , Adolescente , Adulto , Enfermedades Asintomáticas , Citocinas/sangre , Citocinas/genética , Femenino , Hepatitis B Crónica/inmunología , Humanos , Tolerancia Inmunológica , Janus Quinasa 1/metabolismo , Masculino , Análisis por Micromatrices , Pronóstico , Factores de Transcripción STAT/metabolismo , Transducción de Señal , Transcriptoma , Adulto Joven
18.
BMC Infect Dis ; 13: 458, 2013 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-24090287

RESUMEN

BACKGROUND: Hepatitis B e Antigen (HBeAg)-negative chronic hepatitis B (CHB) patients have an active liver disease with a high risk of progression to decompensated cirrhosis and hepatocellular carcinoma. The management strategy for HBeAg-negative CHB patients treated with nucleos(t)ide analogues (NUCs) is a topic of concern. To observe the outcomes for this population after NUCs withdrawal, HBeAg-negative CHB patients with loss of hepatitis B surface antigen (HBsAg) or sustained undetectable HBV DNA levels who had discontinued NUCs therapy were included in the study. METHODS: A total of 66 patients (2 patients with HBsAg loss and 64 patients with sustained undetectable HBV DNA levels) were examined. HBV DNA levels and alanine aminotransferase (ALT) levels were monitored regularly after discontinuation of NUCs therapy. Relapse was defined as HBV DNA levels >2,000 IU/mL while off therapy in at least two determinations more than 4 weeks apart. RESULTS: The time to achieve undetectable HBV DNA levels was 14 weeks (interquartile range (IQR): 12-24 weeks). The time until consolidation therapy was 144 weeks (IQR: 96-168 weeks). No relapses occurred in either of the HBsAg loss patients. Among the 64 patients with undetectable HBV DNA levels, 19 (29.7%) patients demonstrated evidence of relapse. All the relapses occurred within 96 weeks after discontinuation. The median duration of relapse was 36 weeks (IQR: 12-48 weeks). Elevation of HBV DNA and ALT levels over baseline was only observed in 10% of the relapse patients. There were no significant differences among the baseline characteristics (sex, HBV genotype, age, or ALT level) or the time until consolidation therapy between relapse and sustained-response patients. CONCLUSIONS: NUC discontinuation is feasible after achieving undetectable HBV DNA levels in HBeAg-negative CHB patients. Prolonging the time until consolidation therapy may be a good strategy to decrease the rate of relapse. More than 96 weeks of sustained response is a predictive marker of long-term sustained response.


Asunto(s)
Hepatitis B Crónica/tratamiento farmacológico , Nucleósidos/uso terapéutico , Nucleótidos/uso terapéutico , Privación de Tratamiento , Adulto , Antivirales , Femenino , Antígenos e de la Hepatitis B/sangre , Virus de la Hepatitis B , Hepatitis B Crónica/sangre , Hepatitis B Crónica/mortalidad , Hepatitis B Crónica/virología , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Adulto Joven
19.
Front Plant Sci ; 14: 1192425, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37089659

RESUMEN

[This corrects the article DOI: 10.3389/fpls.2022.881856.].

20.
Biomater Sci ; 11(7): 2603-2604, 2023 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-36877216

RESUMEN

Correction for 'Carbazate-modified cross-linked dextran microparticles suppress the progression of osteoarthritis by ROS scavenging' by Yanfeng Ding, et al., Biomater. Sci., 2021, 9, 6236-6250. https://doi.org/10.1039/D1BM00743B.

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