RESUMO
BACKGROUND: Nanoplastics (NPs) are emerging pollutants that pose risks to living organisms. Recent findings have unveiled the reproductive harm caused by polystyrene nanoparticles (PS-NPs) in female animals, yet the intricate mechanism remains incompletely understood. Under this research, we investigated whether sustained exposure to PS-NPs at certain concentrations in vivo can enter oocytes through the zona pellucida or through other routes that affect female reproduction. RESULTS: We show that PS-NPs disrupted ovarian functions and decreased oocyte quality, which may be a contributing factor to lower female fertility in mice. RNA sequencing of mouse ovaries illustrated that the PI3K-AKT signaling pathway emerged as the predominant environmental information processing pathway responding to PS-NPs. Western blotting results of ovaries in vivo and cells in vitro showed that PS-NPs deactivated PI3K-AKT signaling pathway by down-regulating the expression of PI3K and reducing AKT phosphorylation at the protein level, PI3K-AKT signaling pathway which was accompanied by the activation of autophagy and apoptosis and the disruption of steroidogenesis in granulosa cells. Since PS-NPs penetrate granulosa cells but not oocytes, we examined whether PS-NPs indirectly affect oocyte quality through granulosa cells using a granulosa cell-oocyte coculture system. Preincubation of granulosa cells with PS-NPs causes granulosa cell dysfunction, resulting in a decrease in the quality of the cocultured oocytes that can be reversed by the addition of 17ß-estradiol. CONCLUSIONS: This study provides findings on how PS-NPs impact ovarian function and include transcriptome sequencing analysis of ovarian tissue. The study demonstrates that PS-NPs impair oocyte quality by altering the functioning of ovarian granulosa cells. Therefore, it is necessary to focus on the research on the effects of PS-NPs on female reproduction and the related methods that may mitigate their toxicity.
Assuntos
Células da Granulosa , Nanopartículas , Oócitos , Poliestirenos , Transdução de Sinais , Animais , Feminino , Camundongos , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Fertilidade/efeitos dos fármacos , Células da Granulosa/efeitos dos fármacos , Células da Granulosa/metabolismo , Nanopartículas/toxicidade , Oócitos/efeitos dos fármacos , Oócitos/metabolismo , Ovário/efeitos dos fármacos , Ovário/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Poliestirenos/toxicidade , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacosRESUMO
Sophora alopecuroides has important uses in medicine, wind breaking, and sand fixation. The CHY-zinc-finger and RING-finger (CHYR) proteins are crucial for plant growth, development, and environmental adaptation; however, genetic data regarding the CHYR family remain scarce. We aimed to investigate the CHYR gene family in S. alopecuroides and its response to abiotic stress, and identified 18 new SaCHYR genes from S. alopecuroides whole-genome data, categorized into 3 subclasses through a phylogenetic analysis. Gene structure, protein domains, and conserved motifs analyses revealed an exon-intron structure and conserved domain similarities. A chromosome localization analysis showed distribution across 12 chromosomes. A promoter analysis revealed abiotic stress-, light-, and hormone-responsive elements. An RNA-sequencing expression pattern analysis revealed positive responses of SaCHYR genes to salt, alkali, and drought stress. SaCHYR4 overexpression considerably enhanced alkali and drought tolerance in Arabidopsis thaliana. These findings shed light on SaCHYR's function and the resistance mechanisms of S. alopecuroides, presenting new genetic resources for crop resistance breeding.
Assuntos
Regulação da Expressão Gênica de Plantas , Família Multigênica , Filogenia , Proteínas de Plantas , Sophora , Estresse Fisiológico , Estresse Fisiológico/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Sophora/genética , Arabidopsis/genética , Genoma de Planta , Secas , Cromossomos de Plantas/genéticaRESUMO
Long-term accumulation of toxic heavy metals in the environment was a potential hidden danger. High energy consumption, complicated operation and low adsorption capacity were the disadvantages of most current adsorbents. This study used one-step modification of fly ash (FA) by low-temperature melting method with KOH as the activator to generate modified fly ash (KFA) with high adsorption capacity to remove heavy metals from aqueous solutions. Various characterization results revealed a destruction that occurred on the surface structure of adsorbent, 12 times increase in specific surface area, and metal ions were successfully adsorbed onto KFA surface. Furthermore, adsorption proceeded most favorably at pH of 5, the presence of ionic strength and co-existing cations significantly influenced the adsorption effects. The description of adsorption data was more suitable by pseudo-second-order kinetics and Langmuir isotherm models. And in single system at 25 °C, for Pb(II), Cu(II), and Cd (II), the qm were 337.41, 310.09 and 125.00 mg·g-1. However, in ternary system, the qm decreased for all three ions in the order Pb(II) > Cu(II) > Cd(II), which was different from the law in single system, and the Pb(II) adsorption was found to have a significant inhibited effect on adsorption of Cd(II) and Cu(II). The adsorption mechanisms including ion exchange, electrostatic attraction and complexation were revealed. And by exploring the bioaccessibility of absorbed heavy metals in four simulated digestive fluids, it was found that KFA could load heavy metal ions and enable their release in organisms and other aquatic environments, which provided the possibility for subsequent related studies. Therefore, KFA with low energy consumption and high adsorption capacity is equipped a prospective development space on removing heavy metals from wastewater.
Assuntos
Metais Pesados , Poluentes Químicos da Água , Cinza de Carvão , Cádmio/análise , Chumbo , Estudos Prospectivos , Poluentes Químicos da Água/análise , Metais Pesados/química , Íons , Adsorção , Cinética , Concentração de Íons de HidrogênioRESUMO
Soybean (Glycine max (L.) Merr.) is an important source of plant protein, the nutritional quality of which is considerably affected by the content of the sulfur-containing amino acid, methionine (Met). To improve the quality of soybean protein and increase the Met content in seeds, soybean cystathionine γ-synthase 2 (GmCGS2), the first unique enzyme in Met biosynthesis, was overexpressed in the soybean cultivar "Jack", producing three transgenic lines (OE3, OE4, and OE10). We detected a considerable increase in the content of free Met and other free amino acids in the developing seeds of the three transgenic lines at the 15th and 75th days after flowering (15D and 75D). In addition, transcriptome analysis showed that the expression of genes related to Met biosynthesis from the aspartate-family pathway and S-methyl Met cycle was promoted in developing green seeds of OE10. Ultimately, the accumulation of total amino acids and soluble proteins in transgenic mature seeds was promoted. Altogether, these results indicated that GmCGS2 plays an important role in Met biosynthesis, by providing a basis for improving the nutritional quality of soybean seeds.
Assuntos
Aminoácidos , Glycine max , Glycine max/metabolismo , Aminoácidos/metabolismo , Proteínas de Soja/genética , Proteínas de Soja/metabolismo , Proteínas de Plantas/metabolismo , Sementes/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Regulação da Expressão Gênica de PlantasRESUMO
Cullin (CUL) 4A and 4B ubiquitin ligases are often highly accumulated in human malignant neoplasms and are believed to possess oncogenic properties. However, the underlying mechanisms by which CUL4A and CUL4B promote pulmonary tumorigenesis remain largely elusive. This study reports that CUL4A and CUL4B are highly expressed in patients with non-small cell lung cancer (NSCLC), and their high expression is associated with disease progression, chemotherapy resistance, and poor survival in adenocarcinomas. Depletion of CUL4A (CUL4Ak/d) or CUL4B (CUL4Bk/d) leads to cell cycle arrest at G1 and loss of proliferation and viability of NSCLC cells in culture and in a lung cancer xenograft model, suggesting that CUL4A and 4B are oncoproteins required for tumor maintenance of certain NSCLCs. Mechanistically, increased accumulation of the cell cycle-dependent kinase inhibitor p21/Cip1/WAF1 was observed in lung cancer cells on CUL4 silencing. Knockdown of p21 rescued the G1 arrest of CUL4Ak/d or CUL4Bk/d NSCLC cells, and allowed proliferation to resume. These findings reveal that p21 is the primary downstream effector of lung adenocarcinoma dependence on CUL4, highlight the notion that not all substrates respond equally to abrogation of the CUL4 ubiquitin ligase in NSCLCs, and imply that CUL4Ahigh/CUL4Bhigh may serve as a prognostic marker and therapeutic target for patients with NSCLC.
Assuntos
Adenocarcinoma de Pulmão/metabolismo , Proteínas Culina/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Neoplasias Pulmonares/metabolismo , Adenocarcinoma de Pulmão/patologia , Animais , Biomarcadores/metabolismo , Proliferação de Células , Sobrevivência Celular , Progressão da Doença , Resistencia a Medicamentos Antineoplásicos/fisiologia , Feminino , Xenoenxertos , Humanos , Neoplasias Pulmonares/patologia , Camundongos , Camundongos Nus , Prognóstico , Transdução de Sinais/fisiologia , Ubiquitina/metabolismoRESUMO
Vegetable oil is one of the most important components of human nutrition. Soybean (Glycine max) is an important oil crop worldwide and contains rich unsaturated fatty acids. Diacylglycerol acyltransferase (DGAT) is a key rate-limiting enzyme in the Kennedy pathway from diacylglycerol (DAG) to triacylglycerol (TAG). In this study, we conducted further research using T3 AhDGAT3 transgenic soybean. A high-performance gas chromatography flame ionization detector showed that oleic acid (18:1) content and total fatty acid content of transgenic soybean were significantly higher than those of the wild type (WT). However, linoleic acid (18:2) was much lower than that in the WT. For further mechanistic studies, 20 differentially expressed proteins (DEPs) and 119 differentially expressed metabolites (DEMs) were identified between WT (JACK) and AhDGAT3 transgenic soybean mature seeds using proteomic and lipidomics analyses. Combined proteomic and lipidomics analyses showed that the upregulation of the key DEP (lipase GDSL domain-containing protein) in lipid transport and metabolic process induced an increase in the total fatty acid and 18:1 composition, but a decrease in the 18:2 composition of fatty acids. Our study provides new insights into the deep study of molecular mechanism underlying the enhancement of fatty acids in transgenic soybeans, especially oleic acid and total fatty acid, which are enhanced by over-expression of AhDGAT3.
Assuntos
Ácidos Graxos , Glycine max , Ácidos Graxos/metabolismo , Humanos , Lipase/análise , Lipase/metabolismo , Lipidômica , Plantas Geneticamente Modificadas/genética , Proteômica , Sementes/genética , Glycine max/genética , Glycine max/metabolismoRESUMO
BACKGROUND AND OBJECTIVE: The pulmonary embolism severity index (PESI) and simplified PESI (sPESI) are recommended to recognize patients with acute pulmonary thromboembolism (PTE) with low prognosis risk, which is of great significance for treatment. This study aims to verify the influence of hypocalcaemia on the prognosis of patients with PTE and to establish a new prognosis assessment model. METHODS: This is an observational, multicentre study enrolling patients with PTE from February 2010 to June 2020 across 12 Chinese hospitals. Variables in PESI, serum calcium levels and patient survival status as of 5 July 2020 were collected. The area under the curve of the receiver operating characteristic curve, sensitivity, specificity and Youden index were used to evaluate model performance. RESULTS: In the cohort of 4196 patients with PTE, independent associations existed between hypocalcaemia and mid- and long-term mortalities (p <0.05). By including hypocalcaemia, the new 30-day death risk prediction rule, Peking Union Medical College Hospital rule (PUMCH rule), showed significantly higher specificity (0.622 [0.582, 0.661]; p <0.001) than the PESI (0.514 [0.473, 0.554]) and sPESI (0.484 [0.444, 0.525]) and similar sensitivity (0.963 [0.810, 0.999]; p = 0.161) with PESI (0.889 [0.708, 0.976]) and sPESI (0.963 [0.810, 0.999]) in the internal validation cohort. Well-performing predictive validity was also verified on a constructed external validation cohort. CONCLUSION: Hypocalcaemia is independently associated with mid- and long-term PTE mortalities. The PUMCH rule showed significantly higher specificity than the PESI and sPESI and similar sensitivity, which may be used as a prognostic assessment tool for patients with acute PTE.
Assuntos
Hipocalcemia , Embolia Pulmonar , Doença Aguda , Cálcio , Humanos , Hipocalcemia/complicações , Hipocalcemia/diagnóstico , Valor Preditivo dos Testes , Prognóstico , Embolia Pulmonar/complicações , Medição de Risco , Índice de Gravidade de DoençaRESUMO
MAIN CONCLUSION: Overexpression of SaAQP can improve the salt tolerance of transgenic soybean hairy roots and A. thaliana. Salt stress severely affects crop yield and food security. There is a need to improve the salt tolerance of crops, but the discovery and utilization of salt-tolerance genes remains limited. Owing to its strong stress tolerance, Sophora alopecuroides is ideal for the identification of salt-tolerance genes. Therefore, we aimed to screen and identify the salt-tolerance genes in S. alopecuroides. With a yeast expression library of seedlings, salt-tolerant genes were screened using a salt-containing medium to simulate salt stress. By combining salt-treatment screening and transcriptome sequencing, 11 candidate genes related to salt tolerance were identified, including genes for peroxidase, inositol methyltransferase, aquaporin, cysteine synthase, pectinesterase, and WRKY. The expression dynamics of candidate genes were analyzed after salt treatment of S. alopecuroides, and salt tolerance was verified in yeast BY4743. The candidate genes participated in the salt-stress response in S. alopecuroides, and their overexpression significantly improved the salt tolerance of yeast. Salt tolerance mediated by SaAQP was further verified in soybean hairy roots and Arabidopsis thaliana, and it was found that SaAQP might enhance the salt tolerance of A. thaliana by participating in a reactive oxygen species scavenging mechanism. This result provides new genetic resources in plant breeding for salt resistance.
Assuntos
Tolerância ao Sal , Sophora , Regulação da Expressão Gênica de Plantas , Melhoramento Vegetal , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Tolerância ao Sal/genética , Sophora/genética , Sophora/metabolismo , Estresse FisiológicoRESUMO
KEY MESSAGE: Proteomic and lipidomics analyses of WT and GmDGAT1-2 transgenic soybeans showed that GmDGAT1-2 over-expression induced lipoxygenase down-regulatation and oleoin up-regulatation, which significantly changed the compositions and total fatty acid. The main goal of soybean breeding is to increase the oil content. Diacylglycerol acyltransferase (DGAT) is a key rate-limiting enzyme in fatty acid metabolism and may regulate oil content. Herein, 10 GmDGAT genes were isolated from soybean and transferred into wild-type (WT) Arabidopsis. The total fatty acid was 1.2 times higher in T3 GmDGAT1-2 transgenic Arabidopsis seeds than in WT. Therefore, GmDGAT1-2 was transferred into WT soybean (JACK), and four T3 transgenic soybean lines were obtained. The results of high-performance gas chromatography and Soxhlet extractor showed that, compared with those of JACK, oleic acid (18:1), and total fatty acid levels in transgenic soybean plants were much higher, but linoleic acid (18:2) was lower than WT. Palmitic acid (16:0), stearic acid (18:0), and linolenic acid (18:3) were not significantly different. For mechanistic studies, 436 differentially expressed proteins (DEPs) and 180 differentially expressed metabolites (DEMs) were identified between WT (JACK) and transgenic soybean pods using proteomic and lipidomics analyses. Four lipoxygenase proteins were down-regulated in linoleic acid metabolism while four oleosin proteins were up-regulated in the final oil formation. The results showed an increase in the total fatty acid and 18:1 composition, and a decrease in the 18:2 composition of fatty acid. Our study brings new insights into soybean genetic transformation and the deep study of molecular mechanism that changes the total fatty acid, 18:1, and 18:2 compositions in GmDGAT1-2 transgenic soybean.
Assuntos
Diacilglicerol O-Aciltransferase/genética , Glycine max/genética , Lipoxigenase/metabolismo , Proteínas de Membrana/metabolismo , Proteínas de Plantas/metabolismo , Óleo de Soja/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Diacilglicerol O-Aciltransferase/metabolismo , Regulação da Expressão Gênica de Plantas , Ácido Linoleico/genética , Ácido Linoleico/metabolismo , Lipidômica/métodos , Lipoxigenase/genética , Proteínas de Membrana/genética , Família Multigênica , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Proteômica/métodos , Sementes/genética , Sementes/metabolismo , Óleo de Soja/genética , Proteínas de Soja/genética , Proteínas de Soja/metabolismo , Glycine max/metabolismoRESUMO
Salt stress seriously restricts crop yield and quality, leading to an urgent need to understand its effects on plants and the mechanism of plant responses. Although phytohormones are crucial for plant responses to salt stress, the role of phytohormone signal transduction in the salt stress responses of stress-resistant species such as Sophora alopecuroides has not been reported. Herein, we combined transcriptome and metabolome analyses to evaluate expression changes of key genes and metabolites associated with plant hormone signal transduction in S. alopecuroides roots under salt stress for 0 h to 72 h. Auxin, cytokinin, brassinosteroid, and gibberellin signals were predominantly involved in regulating S. alopecuroides growth and recovery under salt stress. Ethylene and jasmonic acid signals may negatively regulate the response of S. alopecuroides to salt stress. Abscisic acid and salicylic acid are significantly upregulated under salt stress, and their signals may positively regulate the plant response to salt stress. Additionally, salicylic acid (SA) might regulate the balance between plant growth and resistance by preventing reduction in growth-promoting hormones and maintaining high levels of abscisic acid (ABA). This study provides insight into the mechanism of salt stress response in S. alopecuroides and the corresponding role of plant hormones, which is beneficial for crop resistance breeding.
Assuntos
Estresse Salino/genética , Transdução de Sinais/genética , Sophora/genética , Ácido Abscísico/metabolismo , Brassinosteroides/metabolismo , Citocininas/genética , Etilenos/metabolismo , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica de Plantas/genética , Ácidos Indolacéticos/metabolismo , Melhoramento Vegetal/métodos , Reguladores de Crescimento de Plantas/genética , Proteínas de Plantas/genética , Ácido Salicílico/metabolismo , Tolerância ao Sal/genética , Sophora/metabolismo , Estresse Fisiológico/genética , Transcriptoma/genética , Regulação para Cima/genéticaRESUMO
Salt stress is the main abiotic stress that limits crop yield and agricultural development. Therefore, it is imperative to study the effects of salt stress on plants and the mechanisms through which plants respond to salt stress. In this study, we used transcriptomics and metabolomics to explore the effects of salt stress on Sophora alopecuroides. We found that salt stress incurred significant gene expression and metabolite changes at 0, 4, 24, 48, and 72 h. The integrated transcriptomic and metabolomic analysis revealed that the differentially expressed genes (DEGs) and differential metabolites (DMs) obtained in the phenylpropanoid biosynthesis pathway were significantly correlated under salt stress. Of these, 28 DEGs and seven DMs were involved in lignin synthesis and 23 DEGs and seven DMs were involved in flavonoid synthesis. Under salt stress, the expression of genes and metabolites related to lignin and flavonoid synthesis changed significantly. Lignin and flavonoids may participate in the removal of reactive oxygen species (ROS) in the root tissue of S. alopecuroides and reduced the damage caused under salt stress. Our research provides new ideas and genetic resources to study the mechanism of plant responses to salt stress and further improve the salt tolerance of plants.
Assuntos
Regulação da Expressão Gênica de Plantas , Metaboloma , Fenilpropionatos/metabolismo , Proteínas de Plantas/metabolismo , Tolerância ao Sal , Sophora/metabolismo , Transcriptoma , Perfilação da Expressão Gênica , Lignina/biossíntese , Proteínas de Plantas/genética , Sophora/genética , Sophora/crescimento & desenvolvimento , Estresse FisiológicoRESUMO
OBJECTIVE: To explore the genetic basis for a Chinese pedigree affected with mental retardation. METHODS: G-banded karyotyping analysis and single nucleotide polymorphism microarray (SNP array) were used to detect the genetic variants within the family, and the origin of the variants was analyzed using UPDtool Statistics software. RESULTS: The patient, a 26-year-old female, was found to have a chromosomal karyotype of 46,XX,dup(4)(q28.2q31.3),and SNP array revealed a 25.71 Mb duplication at 4q28.2-q31.3. The duplication was inherited from her father, and her fetus was found to carry the same duplication. CONCLUSION: The duplication of the patient probably underlay the mental retardation. The gender of the carrier and parental origin of the duplication might have led to the variation in their clinical phenotype.
Assuntos
Testes Genéticos , Trissomia , Adulto , Bandeamento Cromossômico , Feminino , Humanos , Cariotipagem , Masculino , Linhagem , Trissomia/genéticaRESUMO
BACKGROUND: Salinity, alkalinity, and drought stress are the main abiotic stress factors affecting plant growth and development. Sophora alopecuroides L., a perennial leguminous herb in the genus Sophora, is a highly salt-tolerant sand-fixing pioneer species distributed mostly in Western Asia and northwestern China. Few studies have assessed responses to abiotic stress in S. alopecuroides. The transcriptome of the genes that confer stress-tolerance in this species has not previously been sequenced. Our objective was to sequence and analyze this transcriptome. RESULTS: Twelve cDNA libraries were constructed in triplicate from mRNA obtained from Sophora alopecuroides for the control and salt, alkali, and drought treatments. Using de novo assembly, 902,812 assembled unigenes were generated, with an average length of 294 bp. Based on similarity searches, 545,615 (60.43%) had at least one significant match in the Nr, Nt, Pfam, KOG/COG, Swiss-Prot, and GO databases. In addition, 1673 differentially expressed genes (DEGs) were obtained from the salt treatment, 8142 from the alkali treatment, and 17,479 from the drought treatment. A total of 11,936 transcription factor genes from 82 transcription factor families were functionally annotated under salt, alkali, and drought stress, these include MYB, bZIP, NAC and WRKY family members. DEGs were involved in the hormone signal transduction pathway, biosynthesis of secondary metabolites and antioxidant enzymes; this suggests that these pathways or processes may be involved in tolerance towards salt, alkali, and drought stress in S. alopecuroides. CONCLUSION: Our study first reported transcriptome reference sequence data in Sophora alopecuroides, a non-model plant without a reference genome. We determined digital expression profile and discovered a broad survey of unigenes associated with salt, alkali, and drought stress which provide genomic resources available for Sophora alopecuroides.
Assuntos
Perfilação da Expressão Gênica/métodos , Proteínas de Plantas/genética , Sophora/fisiologia , Secas , Regulação da Expressão Gênica de Plantas , Sequenciamento de Nucleotídeos em Larga Escala , Anotação de Sequência Molecular , Família Multigênica , Estresse Salino , Análise de Sequência de RNA , Sophora/genética , Estresse FisiológicoRESUMO
Soil salinity significantly reduces soybean (Glycine max L.) production worldwide. Plants resistance to stress conditions is a complex characteristic regulated by multiple signaling pathways. The v-Myb avian myeloblastosis viral oncogene homolog (MYB) transcription factor (TF) plays a crucial role in plant development, secondary metabolism, and abiotic stress responses. GmMYB68-overexpression and RNA interference (RNAi) lines were established for examining the function of G. max GmMYB68 in plant responses to abiotic stresses. The predicted amino acid sequence of GmMYB68 was similar to that of R2R3-MYB proteins. Quantitative real-time PCR analysis revealed that GmMYB68 expression varied in response to abiotic stresses. GmMYB68-overexpression lines showed enhanced resistance to salt and alkali stresses and their osmotic adjustment and photosynthetic rates were also stronger than that of GmMYB68-RNAi and wild type plants. Although wild type and transgenic plants showed no significant differences in agronomic traits under normal conditions, the overexpression of GmMYB68 increased grain number and 100-grain weights under salt stress. Our study identified a valuable TF associated with stress response in soybean, as its overexpression might help improve salt and alkali tolerance in soybean and other crops.
Assuntos
Glycine max/genética , Proteínas de Plantas/metabolismo , Tolerância ao Sal , Fatores de Transcrição/metabolismo , Álcalis , Fotossíntese , Proteínas de Plantas/química , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Glycine max/metabolismo , Estresse Fisiológico , Fatores de Transcrição/química , Fatores de Transcrição/genéticaRESUMO
DNA damage occurs in a human cell at an average frequency of 10,000 incidences per day by means of external and internal culprits, damage that triggers sequential cellular responses and stalls the cell cycle while activating specific DNA repair pathways. Failure to remove DNA lesions would compromise genomic integrity, leading to human diseases such as cancer and premature aging. If DNA damage is extensive and cannot be repaired, cells undergo apoptosis. DNA damage response (DDR) often entails posttranslational modifications of key DNA repair and DNA damage checkpoint proteins, including phosphorylation and ubiquitination. Cullin-RING ligase 4 (CRL4) enzyme has been found to target multiple DDR proteins for ubiquitination. In this chapter, we will discuss key repair and checkpoint proteins that are subject to ubiquitin-dependent regulation by members of the CRL4 family during ultraviolet light (UV)-induced DNA damage.
Assuntos
Dano ao DNA , Reparo do DNA , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina/metabolismo , Ubiquitinação , Envelhecimento/genética , Envelhecimento/patologia , Animais , Apoptose , Humanos , Neoplasias/genética , Neoplasias/patologiaRESUMO
INTRODUCTION: The objective of this study was to evaluate the characteristics of force degradation of latex elastics of 10 kinds of elastics over 48 hours, both in vivo and in vitro. METHODS: For the in vivo study, 10 different kinds of elastics were randomly chosen for investigation: 1/8-inch (2 oz); 1/8-inch (3.5 oz); 3/16-inch (2 oz); 3/16-inch (3.5 oz); 1/4-inch (2 oz); 1/4-inch (3.5 oz); 5/16-inch (2 oz); 5/16-inch (3.5 oz); 3/8-inch (2 oz); and 3/8-inch (3.5 oz). Ten volunteers (aged 22-24 years) were selected to wear personalized clear retainers, which were made to hold the elastics in the mouth and stretched to a specific length. Control samples of 1/4-inch (2 oz) and 1/4-inch (3.5 oz) latex elastics were stretched to the same length and held in dry air conditions (temperature = 25°C) and in artificial saliva (temperature = 37°C, pH = 6.7). Force value and percentage of force degradation were estimated 10 times over a 48-hour period in both the in vivo and in vitro groups. A 1-way ANOVA and t test were used to identify statistical significance (P <0.05). RESULTS: The force degradation of the latex elastic in vivo is greater than in vitro. In the in vivo groups, during the first hour, the extension rate of all elastics decreased sharply about 13.16%-18.79%, then the rate of force degradation declined. The degradation of initial force was about 29.35%-39.94% after 48 hours. The extension range of 2.0-oz elastics reduced less than that of the 3.5-oz elastics in vivo. At the same time, with the same initial force, elastics with larger inner diameters decreased more slowly than the smaller elastics (P <0.05). CONCLUSIONS: The force degradation of latex elastic in vivo is much greater than that in both air and artificial saliva. In vivo, the force value of the orthodontic latex elastics decreased sharply in the first hour. The larger the inner diameter and smaller the setting force value were, the slower the force decay.
Assuntos
Látex , Aparelhos Ortodônticos , Análise do Estresse Dentário , Elasticidade , Humanos , Teste de Materiais , Estresse Mecânico , Adulto JovemRESUMO
The Cullin-RING ubiquitin ligase 4 (CRL4) is implicated in controlling cell cycle, DNA damage repair, and checkpoint response based on studies employing cell lines and mouse models. CRL4 proteins, including CUL4A and CUL4B, are often highly accumulated in human malignancies. Elevated CRL4 attenuates DNA damage repair and increases genome instability that is believed to facilitate tumorigenesis. However, this has yet to be evaluated in human patients with cancer. In our study, 352 lung cancer and 62 normal lung specimens of Asian origin were constructed into tissue microarrays of four distinct lung cancer subtypes. Expression of CUL4A, CUL4B, and their substrates was detected by immunohistochemistry and analyzed statistically for their prognostic value and association with DNA damage response and genomic instability. Our results show that both CUL4A and CUL4B are overexpressed in the majority of lung carcinomas (PCUL4A <0.001 and PCUL4B <0.001) and significantly associated with tumor size (PCUL4A <0.001 and PCUL4B = 0.002), lymphatic invasion (PCUL4A = 0.004 and PCUL4B <0.001), metastasis (PCUL4A = 0.019 and PCUL4B = 0.006), and advanced TNM stage (PCUL4A <0.001 and PCUL4B <0.001), which parallels gene amplification and abnormal activation of the canonical WNT signaling. Moreover, overexpression of CUL4A, but not CUL4B, is significantly associated with tobacco smoking (p = 0.01) and is inversely correlated with XPC and P21, both of which are substrates of CUL4A (PCUL4A = 0.019 and PCUL4B = 0.006). Higher levels of CUL4A or CUL4B are significantly associated with the overall survival of patients (PCUL4A <0.001 and PCUL4B <0.001) and progression-free survival (PCUL4A <0.001 and PCUL4B = 0.001). Our findings revealed that CUL4A and CUL4B are differentially associated with etiologic factors for pulmonary malignancies and are independent prognostic markers for the survival of distinct lung cancer subtypes.
Assuntos
Proteínas Culina/metabolismo , Neoplasias Pulmonares/enzimologia , Ubiquitina-Proteína Ligases/metabolismo , Linhagem Celular Tumoral , Proteínas Culina/genética , Humanos , Imuno-Histoquímica , Neoplasias Pulmonares/classificação , Neoplasias Pulmonares/patologia , Prognóstico , Fumar , Especificidade por Substrato , Análise de Sobrevida , Ubiquitina-Proteína Ligases/genéticaRESUMO
Myeloblastosis (MYB) transcription factor (TF) plays a positive role in the growth and stress response of plants; however, information on the functions of MYB repressors in soybean is limited. In the present study, the gene GmMYB3a was identified and characterized as a member of the R2R3 MYB repressor family, which is induced by various abiotic stresses. To understand the functions of GmMYB3a, a transgenic soybean over-expressing GmMYB3a was obtained and the photosynthetic index under salt-alkali treatments was evaluated. The transgenic line exhibited a series of negative regulation relative to the wild-type control. Quantitative real time polymerase chain reaction revealed that the physiological parameters, including soluble sugar, free proline, and chlorophyll contents; and photosynthetic rate decreased in the transgenic plants. Furthermore, GmMYB3a overexpression down-regulated a set of key genes associated with plant defense signal pathways. These finding suggest that GmMYB3a negatively affects the response of plants to salt stress.
Assuntos
Regulação da Expressão Gênica de Plantas , Glycine max/genética , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/genética , Proteínas Repressoras/genética , Tolerância ao Sal , Sequência de Aminoácidos , Genes de Plantas , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/química , Plantas Geneticamente Modificadas/fisiologia , Proteínas Repressoras/química , Proteínas Repressoras/metabolismo , Alinhamento de Sequência , Glycine max/química , Glycine max/fisiologia , Estresse Fisiológico , Regulação para CimaRESUMO
Propylaea japonica (Thunberg) was a dominant species among the predacious ladybirds in the fields and active from March to November during a year in Fuzhou, China. Stability of insecticide resistance and vitality in adult P. japonica were investigated. The field ladybird P. japonica in Fuzhou, China, showed 9- to 16-fold resistance ratios to chlorpyrifos, 13- to 2,083-fold to methamidophos, 32- to 230-fold to fenvalerate, and 4- to 49-fold to avermectins, respectively, based on the field monitoring during 2004, 2009, and 2012, as compared with insecticide-susceptible F39 progenies. The resistance levels in the field P. japonica were high during May and November but low during summer. The population growth tendency index in field P. japonica was 0.8-fold as high as that in insecticide-susceptible P. japonica. The field P. japonica also showed high tolerance to the insecticide as compared with pest Lipaphis erysimi Kaltenbach and two parasitoids Diaeretiella rapae and Pachyneuron aphidis. Stable insecticide resistance levels and high vitality were found first in adult P. japonica with 1-, 30-, or 60-d-old adults, or among the adults developed form the eggs produced by newly emerged adults or by 60-d-old adults. Increased activity of glutathione S-transferases, carboxylesterases, and cytochrome P450 monooxygenases might be involved in the resistance of P. japonica. The results indicated that, in certain areas, inclusion of P. japonica for pest control in the integrated pest management would be highly recommended.
Assuntos
Besouros , Resistência a Inseticidas/fisiologia , Inseticidas , Animais , China , Estações do AnoRESUMO
Immunotherapy for cancer treatment is achieved through the activation of competent immune effector cells and the inhibition of immunosuppressive cells, such as myeloid-derived suppressor cells (MDSCs). Although MDSCs have been shown to contribute to breast cancer development, the mechanism underlying MDSC-mediated immunosuppression is unclear. We have identified a poorly differentiated MDSC subset in breast cancer-suppressing T cell function through STAT3-dependent IDO upregulation. In this study we investigated the mechanisms underlying aberrant expression of IDO in MDSCs. MDSCs were induced by coculturing human CD33(+) myeloid progenitors with MDA-MB-231 breast cancer cells. Increased STAT3 activation in MDSCs was correlated with activation of the noncanonical NF-κB pathway, including increased NF-κB-inducing kinase (NIK) protein level, phosphorylation of cytoplasmic inhibitor of NF-κB kinase α and p100, and RelB-p52 nuclear translocation. Blocking STAT3 activation with the small molecule inhibitor JSI-124 significantly inhibited the accumulation of NIK and IDO expression in MDSCs. Knockdown of NIK in MDSCs suppressed IDO expression but not STAT3 activation. RelB-p52 dimers were found to directly bind to the IDO promoter, leading to IDO expression in MDSCs. IL-6 was found to stimulate STAT3-dependent, NF-κB-mediated IDO upregulation in MDSCs. Furthermore, significant positive correlation between the numbers of pSTAT3(+) MDSCs, IDO(+) MDSCs, and NIK(+) MDSCs was observed in human breast cancers. These results demonstrate a STAT3/NF-κB/IDO pathway in breast cancer-derived MDSCs, which provides insight into understanding immunosuppressive mechanisms of MDSCs in breast cancer.