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1.
Materials (Basel) ; 16(7)2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-37048957

RESUMO

The quantity of waste from end-of-life vehicles is increasing with an increase in the number of scrapped internal combustion engine vehicles owing to international trends such as carbon neutrality and particulate matter reduction. The recycling rate must be ≥95%; however, the average recycling rate remains at approximately 89%. Therefore, the improvement of the recycling of automobile shredder residues (ASR) is gaining attention. In this study, four types of products (interlocking, clay, and lightweight swelled ceramic (LSC) bricks, and asphalt paving aggregate (APA)) were manufactured using ASR melting slag (ASRMS). Environmental performance, quality standards, and technology were evaluated to assess the recyclability of the manufactured bricks. The interlocking brick substituted melting slag for sand and stone powder as an aggregate. As melting slag content increased, absorption decreased and bending strength increased. Clay brick was manufactured by replacing kaolin and feldspar with melting slag that substituted for 20%. The quality of clay bricks mixed with over 15% melting slag was not better than standard. Asphalt paving aggregate was used to investigate the optimum condition of slag content in mixed asphalt; the mixture ratio showed that 61% broken stone of 13 mm, 6% screenings, 10% melting slag, 15% sand and 8% filler was most effective. A lightweight swelled ceramic brick was manufactured by using melting slag, front glass, and so on. Specific gravity and compressive strength ranged from 0.38 to 0.51 and from 339.7 to 373.6 N/cm2. ASRMS exhibited an environmental performance suitable for recycling and the manufactured bricks satisfied the quality standards. The recyclability of ASR was also assessed in terms of waste usage, conformance to quality standards, market size, and demand prediction. APA showed the best results followed by interlocking, clay, and LSC bricks.

2.
RSC Adv ; 12(52): 33653-33665, 2022 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-36505717

RESUMO

The preparation of sunblocks with dispersion stability, ultraviolet blocking, and photocompatibility remains a considerable challenge. Plant-derived natural polymers, such as cellulose nanofibers (CNF), show versatile traits, including long aspect ratio, hydrophilic nature, resource abundance, and low material cost. In the present study, a facile and cost-effective strategy is reported for the fabrication of nanostructured inorganic materials by incorporating natural polymers as interspersed, systematically nanosized titanium dioxide (TiO2) particles onto CNF. Among all experiments, the optimized TiO2@CNF3 showed higher ultraviolet blocking performance and less whitening effect. The outstanding performance is attributed to the engineering of equally dispersed nano-sized TiO2 particles on the CNF surface and stable dispersion. Significantly, TiO2@CNF3 exhibited excellent compatibility with avobenzone (80%), an oil-soluble ingredient used in sunblock products, illustrating the photoprotection enhancement under ultraviolet A (UVA) and ultraviolet B (UVB). Moreover, only 14.8% rhodamine B (Rho-B) dye degraded through photocatalytic oxidation process with the TiO2@CNF3, which is negligible photocatalytic activity compared to that of TiO2 (95% dye degraded). Furthermore, commercial inorganic and organic sunblock products with SPF lifetimes of 35+ and 50+ were modified using CNF, significantly enhancing the transmittance performance compared to that of the pure sunblock. However, it was also observed that hydrophilic CNF tended to demulsify the creams due to electrostatic disequilibrium. This CNF-based modified TiO2 system is a new window to replace effective sunblock products in high-value-added applications, such as cosmetics.

3.
Antioxidants (Basel) ; 11(12)2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36552637

RESUMO

Oenanthe javanica, commonly known as water dropwort, has long been used to treat acute and chronic hepatitis, abdominal pain, alcohol hangovers, and inflammation in various traditional medicine systems in Asia. However, whether O. javanica has beneficial effects on colitis-induced intestinal damage remains elusive. This study tested the hypothesis that O. javanica has anti-inflammatory and antioxidant activities in mice with dextran sulfate sodium (DSS)-induced colitis. First, treatment of O. javanica ethanol extract (OJE) inhibited the production of inflammatory cytokines in lipopolysaccharide-affected macrophages. Second, in mice with DSS-induced colitis, OJE administration reduced pathological damage to the colon while alleviating weight gain and decreasing colon length, including inflammation and mucosal necrosis. In addition, OJE significantly (p < 0.01) restricted the activation of nuclear factor-κB (NF-κB) and the secretion of pro-inflammatory mediators and increased the expression of Nrf2-phase 2 antioxidant enzymes. The results of 16S rRNA gene sequencing workflows for taxonomic assignment analysis confirmed that the diversity (richness and evenness) of fecal microbiota was markedly elevated in the OJE group. OJE administration reduced the abundance of Proteobacteria including Escherichia and increased the abundance of the genus Muribaculum. These results suggested that OJE exerts beneficial effects on inflammation and gut microbial composition in a mouse model of colitis.

4.
Cancers (Basel) ; 14(8)2022 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-35454897

RESUMO

Alternative splicing (AS) is a procedure during gene expression that allows the production of multiple mRNAs from a single gene, leading to a larger number of proteins with various functions. The alternative splicing (AS) of Fas (Apo-1/CD95) pre-mRNA can generate membrane-bound or soluble isoforms with pro-apoptotic and anti-apoptotic functions. SRSF6, a member of the Serine/Arginine-rich protein family, plays essential roles in both constitutive and alternative splicing. Here, we identified SRSF6 as an important regulatory protein in Fas AS. The cassette exon inclusion of Fas was decreased by SRSF6-targeting shRNA treatment, but increased by SRSF6 overexpression. The deletion and substitution mutagenesis of the Fas minigene demonstrated that the UGCCAA sequence in the cassette exon of the Fas gene causes the functional disruption of SRSF6, indicating that these sequences are essential for SRSF6 function in Fas splicing. In addition, biotin-labeled RNA-pulldown and immunoblotting analysis showed that SRSF6 interacted with these RNA sequences. Mutagenesis in the splice-site strength alteration demonstrated that the 5' splice-site, but not the 3' splice-site, was required for the SRSF6 regulation of Fas pre-mRNA. In addition, a large-scale RNA-seq analysis using GTEX and TCGA indicated that while SRSF6 expression was correlated with Fas expression in normal tissues, the correlation was disrupted in tumors. Furthermore, high SRSF6 expression was linked to the high expression of pro-apoptotic and immune activation genes. Therefore, we identified a novel RNA target with 5' splice-site dependence of SRSF6 in Fas pre-mRNA splicing, and a correlation between SRSF6 and Fas expression.

5.
J Hazard Mater ; 384: 121291, 2020 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-32028549

RESUMO

The need for appropriate management of mercury (Hg) wastes is increasing for active implementation of the Minamata Convention on Mercury. Though Hg can be a contaminant if it is not dealt with properly, recovered Hg can become a resource. Besides, a recovered Hg with reduced volume can be managed efficiently. This study examined the effect of NaOH for the recovery of elemental Hg from a waste sludge from an industrial process using the thermal desorption and condensation. For this purpose, the operating conditions, including temperature and pressure of the apparatus, were derived based on the experiments using Hg compounds (HgS and HgO), simulated waste (mixtures of HgCl2/As2O3 and HgS/As2O3). The reduced chamber pressure promoted to the recovery of elemental Hg via the thermal desorption. NaOH was introduced to increase the recovery efficiency of Hg in the presence of interfering substances such as S and As compounds. The Hg recovery efficiency increased, and 62.5% of Hg was recovered as elemental form by adding NaOH via thermal desorption and gas condensation with a lab-scale apparatus. Interfering substances such as Cl, S, and As compounds were captured in the bottom ash when bound with Na.

6.
BMB Rep ; 52(11): 641-646, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31401978

RESUMO

The Ron proto-oncogene is a human receptor for macrophage-stimulating protein (MSP). The exclusion of exon 11 in alternative splicing generates ΔRON protein that is constitutively activated. Heterogenous ribonucleaoprotein (hnRNP) C1/C2 is one of the most abundant proteins in cells. In this manuscript, we showed that both hnRNP C1 and C2 promoted exon 11 inclusion of Ron pre-mRNA and that hnRNP C1 and hnRNP C2 functioned independently but not cooperatively. Moreover, hnRNP C1 stimulated exon 11 splicing through intron 10 activation but not through intron 11 splicing. Furthermore, we showed that, whereas the RRM domain was required for hnRNP C1 function, the Asp/Glu domain was not. In conclusion, hnRNP C1/C2 promoted exon 11 splicing independently by stimulating intron 10 splicing through RRM but not through the Asp/Glu domain. [BMB Reports 2019; 52(11): 641-646].


Assuntos
Ribonucleoproteínas Nucleares Heterogêneas Grupo C/genética , Precursores de RNA/metabolismo , Motivo de Reconhecimento de RNA/genética , Processamento Alternativo/genética , Processamento Alternativo/fisiologia , Éxons/genética , Células HEK293 , Células HeLa , Ribonucleoproteínas Nucleares Heterogêneas Grupo C/metabolismo , Ribonucleoproteínas Nucleares Heterogêneas , Humanos , Íntrons/genética , Proteínas Nucleares/metabolismo , Proto-Oncogene Mas , Splicing de RNA , Receptores Proteína Tirosina Quinases/genética , Receptores Proteína Tirosina Quinases/metabolismo
7.
Cells ; 8(7)2019 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-31295920

RESUMO

Here we show that the serine/arginine rich splicing factor 2 (SRSF2) promotes cryptic 3' splice-site (3'AG') usage during cassette exon exclusion in survival of motor neuron (SMN2) minigenes. Deletion of the 3'AG' (3'AG'1), its associated branch point (BP') and polypyrimidine tract (PPT') sequences directs SRSF2 to promote a second 3'AG' (3'AG'2) with less conserved associated region for intron splicing. Furthermore, deletion of both 3'AG'1 and 3'AG'2 and their associated sequences triggered usage of a third 3'AG'3 that has very weak associated sequences. Interestingly, when intron splicing was directed to the 3'AG' cryptic splice-sites, intron splicing from the canonical 3'AG splice-site was reduced along with a decrease in cassette exon inclusion. Moreover, multiple SRSF2 binding sites within the intron are responsible for 3'AG' activation. We conclude that SRSF2 facilitates exon exclusion by activating a cryptic 3'AG' and inhibiting downstream intron splicing.


Assuntos
Éxons , Fatores de Processamento de Serina-Arginina/metabolismo , Processamento Alternativo , Sítios de Ligação , Células HEK293 , Humanos , Íntrons , Precursores de RNA/genética , Precursores de RNA/metabolismo , Sítios de Splice de RNA , Splicing de RNA , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/genética , Fatores de Processamento de Serina-Arginina/genética , Proteína 2 de Sobrevivência do Neurônio Motor/genética , Proteína 2 de Sobrevivência do Neurônio Motor/metabolismo
8.
J Environ Sci (China) ; 80: 58-65, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30952353

RESUMO

Elemental mercury (Hg0) is predominant constituent of flue gas emitted from coal-fired power plants. Adsorption has been considered the best available technology for removal of Hg0 from flue gas. However, adsorbent injection increases the amount of ash generated. In the present study, powdered activated carbon (PAC) was coated on polytetrafluoroethylene/glass fiber filters to increase Hg0 removal while concurrently reducing the amount of ash generated. The optimal PAC coating rate was determined in laboratory experiments to ensure better Hg0 removal with low pressure drop. When PAC of particle size less than 45 µm was used, and the areal density was 50 g/m2, the pressure drop remained under 30 Pa while the Hg0 removal efficiency increased to 15.8% from 4.3%. The Hg0 removal efficiency also increased with decrease in filtration velocity. The optimal PAC coating rate was applied on a hybrid filter (HF), which was combined with a bag filter and an electrostatic precipitator in a single chamber. Originally designed to remove fine particulates matter, it was retrofitted to the flue gas control device for simultaneous Hg0 removal. By employing the PAC coating, the Hg removal efficiency of the HF increased to 79.79% from 66.35%. Also, a temporary reduction in Hg removal was seen but this was resolved following a cleaning cycle in which the dust layer was removed.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/prevenção & controle , Carvão Vegetal/química , Filtração/métodos , Mercúrio/análise , Poluentes Atmosféricos/química , Mercúrio/química , Centrais Elétricas
9.
Biochem Biophys Res Commun ; 506(3): 703-708, 2018 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-30376989

RESUMO

Alternative splicing of exon 6 in Fas pre-mRNA generates a membrane bound pro-apoptotic isoform or soluble anti-apoptotic isoform. SRSF4 is a member of Arginine-Serine rich (SR) protein family. Here we demonstrate that increased SRSF4 expression stimulates exon 6 inclusion, and that reduced SRSF4 expression promotes exon 6 exclusion. We also show that weaker but not stronger 5' splice-site strength of exon 6 abolishes the SRSF4 effects on exon 6 splicing. Furthermore, we identified a novel enhancer on exon 6, on which SRSF4 interacts functionally and physically. Our results illustrate a novel regulatory mechanism of Fas pre-mRNA splicing.


Assuntos
Elementos Facilitadores Genéticos/genética , Éxons/genética , Precursores de RNA/metabolismo , Splicing de RNA/genética , Fatores de Processamento de Serina-Arginina/metabolismo , Receptor fas/genética , Sequência de Bases , Regulação da Expressão Gênica , Células HCT116 , Humanos , Ligação Proteica/genética , Precursores de RNA/genética , Sítios de Splice de RNA/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptor fas/metabolismo
10.
Environ Pollut ; 237: 531-540, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29524875

RESUMO

The hybrid filter (HF) was newly designed and operated with powder activated carbon (PAC) injection to capture mercury and fine particulate matter in the coal power plant. With PAC injection in HF operation, the capture efficiency of elemental mercury was clearly enhanced. When the injection rate of PAC increased from 0 to 20 mg/m3, the speciation fraction of elemental mercury significantly decreased from 85.19% to 3.76% at the inlet of the hybrid filter. The speciation fraction of oxidized mercury did not vary greatly, whereas the particulate mercury increased from 1.31% to 94.04%. It was clearly observed that the HF played a role in the capture of mercury and fine PM by leading the conversion of elemental mercury as particulate mercury and the growth of PM via electrode discharge in the HF operation with PAC injection.


Assuntos
Poluentes Atmosféricos/análise , Carbono/química , Filtração/instrumentação , Mercúrio/análise , Material Particulado/análise , Poluentes Atmosféricos/química , Carbono/análise , Carvão Vegetal , Carvão Mineral/análise , Mercúrio/química , Compostos de Mercúrio , Óxidos , Material Particulado/química , Centrais Elétricas
11.
BMB Rep ; 50(8): 423-428, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28712387

RESUMO

SRSF2, a Serine-Arginine rich (SR) protein, is a splicing activator that mediates exon inclusion and exclusion events equally well. Here we show SRSF2 directly suppresses intron splicing to suppress cassette exon inclusion in SMN premRNA. Through a serial mutagenesis, we demonstrate that a 10 nt RNA sequence surrounding the branch-point (BP), is important for SRSF2-mediated inhibition of cassette exon inclusion through directly interacting with SRSF2. We conclude that SRSF2 inhibits intron splicing to promote exon exclusion. [BMB Reports 2017; 50(8): 423-428].


Assuntos
Éxons , Íntrons , Fatores de Processamento de Serina-Arginina/genética , Fatores de Processamento de Serina-Arginina/metabolismo , Processamento Alternativo , Sequência de Bases , Células HEK293 , Humanos , Mutagênese Insercional , Precursores de RNA/genética , Precursores de RNA/metabolismo , Splicing de RNA , Fatores de Processamento de RNA/metabolismo , Elementos Reguladores de Transcrição , Proteínas do Complexo SMN/metabolismo
12.
Oncol Lett ; 13(3): 1944-1948, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28454348

RESUMO

The récepteur d'origine nantais (RON) gene is a proto-oncogene that is responsible for encoding the human macrophage-stimulating protein (MSP) 1 receptor. MSP activation induces RON-mediated cell dissociation, migration and matrix invasion. Isoforms of RON that exclude exons 5 and 6 encode the RONΔ160 protein, which promotes cell transformation in vitro and tumor metastasis in vivo. Premature termination codons (PTCs) in exons activate the nonsense-mediated mRNA decay (NMD) signaling pathway. The present study demonstrated that PTCs at various locations in the alternative exons 5 and 6 could induce NMD of the majority of the spliced, or partially spliced, isoforms. However, the isoforms that excluded exon 6 or exons 5 and 6 were markedly increased when produced from mutated minigenes with inserted PTCs. Furthermore, the unspliced isoform of intron 5 was not observed to be decreased by the presence of PTCs. Notably, these effects may be dependent on the location of the PTCs. The current study demonstrated a novel mechanism underlying the regulation of NMD in alternative splicing.

13.
Biochim Biophys Acta Gene Regul Mech ; 1860(3): 363-373, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28119102

RESUMO

Selection of 5' splice-sites (5'SS) in alternative splicing plays an important role in gene regulation. Although regulatory mechanisms of heterogeneous nuclear ribonucleoprotein L (hnRNP L), a well-known splicing regulatory protein, have been studied in a substantial level, its role in 5'SS selection is not thoroughly defined. By using a KLF6 pre-mRNA alternative splicing model, we demonstrate in this report that hnRNP L inhibits proximal 5'SS but promotes two consecutive distal 5'SS splicing, antagonizing SRSF1 roles in KLF6 pre-mRNA splicing. In addition, three consecutive CA-rich sequences in a CA cassette immediately upstream of the proximal 5'SS are all required for hnRNP L functions. Importantly, the CA-cassette locations on the proximal exon do not affect hnRNP L roles. We further show that the proximal 5'SS but not the two distal 5'SSs are essential for hnRNP L activities. Notably, in a Bcl-x pre-mRNA model that contains two alternative 5'SS but includes CA-rich elements at distal exon, we demonstrate that hnRNP L also suppresses nearby 5'SS activation. Taken together, we conclude that hnRNP L suppresses 5'SS selection through multiple exonic motifs.


Assuntos
Éxons , Motivos de Nucleotídeos , Precursores de RNA/metabolismo , Sítios de Splice de RNA/fisiologia , Splicing de RNA/fisiologia , Ribonucleoproteínas/metabolismo , Linhagem Celular Tumoral , Humanos , Fator 6 Semelhante a Kruppel , Fatores de Transcrição Kruppel-Like/biossíntese , Fatores de Transcrição Kruppel-Like/genética , Proteínas Proto-Oncogênicas/biossíntese , Proteínas Proto-Oncogênicas/genética , Precursores de RNA/genética , Ribonucleoproteínas/genética , Fatores de Processamento de Serina-Arginina/biossíntese , Fatores de Processamento de Serina-Arginina/genética
14.
BMB Rep ; 49(11): 612-616, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27530682

RESUMO

CD44 pre-mRNA includes 20 exons, of which exons 1-5 (C1-C5) and exons 16-20 (C6-C10) are constant exons, whereas exons 6-15 (V1-V10) are variant exons. V6-exon-containing isoforms have been known to be implicated in tumor cell invasion and metastasis. In the present study, we performed a SR protein screen for CD44 V6 splicing using overexpression and lentivirus-mediated shRNA treatment. Using a CD44 V6 minigene, we demonstrate that increased SRSF3 and SRSF4 expression do not affect V6 splicing, but increased expression of SRSF1, SRSF6 and SRSF9 significantly inhibit V6 splicing. In addition, using a constitutive exon-specific primer set, we could not detect alterations of CD44 splicing after SR protein-targeting shRNA treatment. However, using a V6 specific primer, we identified that reduced SRSF2 expression significantly reduced the V6 isoform, but increased V6-10 and V6,7-10 isoforms. Our results indicate that SR proteins are important regulatory proteins for CD44 V6 splicing. [BMB Reports 2016; 49(11): 612-616].


Assuntos
Receptores de Hialuronatos/genética , Precursores de RNA/metabolismo , Fatores de Processamento de Serina-Arginina/metabolismo , Éxons , Humanos , Receptores de Hialuronatos/metabolismo , Células MCF-7 , Isoformas de Proteínas/antagonistas & inibidores , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Interferência de RNA , Splicing de RNA , RNA Interferente Pequeno/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Processamento de Serina-Arginina/antagonistas & inibidores , Fatores de Processamento de Serina-Arginina/genética
15.
Methods Mol Biol ; 1421: 35-44, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26965255

RESUMO

RNA-protein interaction can be detected by RNA pull-down and immunoblotting methods. Here, we describe a method to detect RNA-protein interaction using RNA pull down and to identify the proteins that are pulled-down by the RNA using immunoblotting. In this protocol, RNAs with specific sequences are biotinylated and immobilized onto Streptavidin beads, which are then used to pull down interacting proteins from cellular extracts. The presence of a specific protein is subsequently verified by SDS- polyacrylamide gel electrophoresis and immunoblotting with antibodies. Interactions between the SMN RNA and the PSF protein and between the caspase-2 RNA and the SRSF3 protein (SRp20) in nuclear extract prepared from HeLa cells are illustrated as examples.


Assuntos
Immunoblotting/métodos , Proteínas/metabolismo , RNA/metabolismo , Biotinilação , Eletroforese em Gel de Poliacrilamida/métodos , Células HeLa , Humanos , Ligação Proteica , Proteínas/análise , RNA/análise , Fatores de Processamento de Serina-Arginina/análise , Fatores de Processamento de Serina-Arginina/metabolismo , Estreptavidina/metabolismo
16.
J Cancer ; 6(12): 1346-51, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26640595

RESUMO

RON receptor tyrosine kinase is a proto-oncogene that induces cell migration and matrix invasion. RONΔ160 protein, which is produced by exclusion of exon 5 and 6, promotes cell migration, matrix invasion and protection from apoptosis. Alternative splicing regulation of exon 5 and 6 is not well understood. In this manuscript, we identified several new RNA regulatory elements for alternative splicing of Ron proto-oncogene. Firstly, we demonstrated that RNA sequences from EcoRI cleavage sites regulate alternative splicing of Ron exon 5 and 6. Secondly, we showed that the ~30 nt RNA at upstream end of exon 4 and the ~33 nt RNA at downstream end of exon 7 also modulate splicing of exon 5 and 6. Thirdly, our results indicate that the RNA sequences of the ends in exon 4 and 7 are required for the regulatory functions of the RNA from restriction enzyme cleavage sites. Our results provide a new insight for regulation of alternative splicing of Ron proto-oncogene.

17.
Proc Natl Acad Sci U S A ; 112(32): 9926-31, 2015 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-26216990

RESUMO

U2 snRNP auxiliary factor 65 kDa (U2AF(65)) is a general splicing factor that contacts polypyrimidine (Py) tract and promotes prespliceosome assembly. In this report, we show that U2AF(65) stimulates alternative exon skipping in spinal muscular atrophy (SMA)-related survival motor neuron (SMN) pre-mRNA. A stronger 5' splice-site mutation of alternative exon abolishes the stimulatory effects of U2AF(65). U2AF(65) overexpression promotes its own binding only on the weaker, not the stronger, Py tract. We further demonstrate that U2AF(65) inhibits splicing of flanking introns of alternative exon in both three-exon and two-exon contexts. Similar U2AF(65) effects were observed in Fas (Apo-1/CD95) pre-mRNA. Strikingly, we demonstrate that U2AF(65) even inhibits general splicing of adenovirus major late (Ad ML) or ß-globin pre-mRNA. Thus, we conclude that U2AF(65) possesses a splicing Inhibitory function that leads to alternative exon skipping.


Assuntos
Processamento Alternativo/genética , Éxons/genética , Proteínas Nucleares/genética , Ribonucleoproteínas/genética , Sequência de Bases , Proteínas de Ligação a DNA/genética , Células HEK293 , Humanos , Íntrons/genética , Dados de Sequência Molecular , Proteínas Nucleares/química , Ligação Proteica , Estrutura Terciária de Proteína , Precursores de RNA/genética , Precursores de RNA/metabolismo , Sítios de Splice de RNA/genética , Ribonucleoproteínas/química , Proteínas do Complexo SMN/genética , Fator de Processamento U2AF , Relação Estrutura-Atividade , Fatores de Transcrição/genética , Proteínas Virais/genética , Globinas beta/genética , Proteínas tau/genética
18.
ACS Appl Mater Interfaces ; 7(18): 9841-50, 2015 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-25875313

RESUMO

The design of amphiphilic polymer compatibilizers for solubility manipulation of CNT composites was systematically generalized in this study. Structurally tailored multiamphiphilic compatibilizer were designed and synthesized by applying simple, high-yield reactions. This multiamphiphilic compatibilizer was applied for noncovalent functionalization of CNTs as well as provided CNTs with outstanding dispersion stability, manipulation of solubility, and hybridization with Ag nanoparticles (NPs). With regard to the dispersion properties, superior records in maximum concentration (2.88-3.10 mg/mL in chloroform), and mass ratio of the compatibilizer for good CNT dispersion (36 wt %) were achieved by MWCNTs functionalized with a multiamphiphilic block copolymer compatibilizer. In particular, the solubility limitations of MWCNT dispersion in solvents ranging from toluene (nonpolar) to aqueous solution (polar) are surprisingly resolved by introducing this multiamphiphilic polymer compatibilizer. Furthermore, this polymer compatibilizer allowed the synthesis of the hybrid CNT nanocomposites with Ag nanoparticles by an in situ nucleation process. As such, the multiamphiphilic compatibilizer candidate as a new concept for the noncovalent functionalization of CNTs can extend their use for a wide range of applications.

19.
Biochim Biophys Acta ; 1849(6): 743-50, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25623890

RESUMO

CD44 is a complex cell adhesion molecule that mediates communication and adhesion between adjacent cells as well as between cells and the extracellular matrix. CD44 pre-mRNA produces various mRNA isoforms through alternative splicing of 20 exons, among which exons 1-5 (C1-C5) and 16-20 (C6-C10) are constant exons, whereas exons 6-15 (V1-V10) are variant exons. CD44 V10 exon has important roles in breast tumor progression and Hodgkin lymphoma. Here we show that increased expression of hnRNP L inhibits V10 exon splicing of CD44 pre-mRNA, whereas reduced expression of hnRNP L promotes V10 exon splicing. In addition, hnRNP L also promotes V10 splicing of endogenous CD44 pre-mRNA. Through mutation analysis, we demonstrate that the effects of hnRNP L on V10 splicing are abolished when the CA-rich sequence on the upstream intron of V10 exon is disrupted. However, hnRNP L effects are stronger if more CA-repeats are provided. Furthermore, we show that hnRNP L directly contacts the CA-rich sequence. Importantly, we provide evidences that hnRNP L inhibits U2AF65 binding on the upstream Py tract of V10 exon. Our results reveal that hnRNP L is a new regulator for CD44 V10 exon splicing.


Assuntos
Ribonucleoproteínas Nucleares Heterogêneas Grupo L/biossíntese , Receptores de Hialuronatos/genética , Íntrons/genética , Splicing de RNA/genética , Adesão Celular/genética , Éxons/genética , Regulação da Expressão Gênica , Células HeLa , Ribonucleoproteínas Nucleares Heterogêneas Grupo L/metabolismo , Humanos , Receptores de Hialuronatos/metabolismo , Proteínas Nucleares/metabolismo , Ribonucleoproteínas/metabolismo , Fator de Processamento U2AF
20.
Biochim Biophys Acta ; 1839(11): 1132-40, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25220236

RESUMO

The product of proto-oncogene Ron is a human receptor for the macrophage-stimulating protein (MSP). Upon activation, Ron is able to induce cell dissociation, migration and matrix invasion. Exon 11 skipping of Ron pre-mRNA produces Ron△165 protein that is constitutively active even in the absence of its ligand. Here we show that knockdown of SRSF2 promotes the decrease of exon 11 inclusion, whereas overexpression of SRSF2 promotes exon 11 inclusion. We demonstrate that SRSF2 promotes exon 11 inclusion through splicing and transcription procedure. We also present evidence that reduced expression of SRSF2 induces a decrease in the splicing of both introns 10 and 11; by contrast, overexpression of SRSF2 induces an increase in the splicing of introns 10 and 11. Through mutation analysis, we show that SRSF2 functionally targets and physically interacts with CGAG sequence on exon 11. In addition, we reveal that the weak strength of splice sites of exon 11 is not required for the function of SRSF2 on the splicing of Ron exon 11. Our results indicate that SRSF2 promotes exon 11 inclusion of Ron proto-oncogene through targeting exon 11. Our study provides a novel mechanism by which Ron is expressed.


Assuntos
Proteínas Nucleares/fisiologia , Splicing de RNA , Receptores Proteína Tirosina Quinases/genética , Ribonucleoproteínas/fisiologia , Transcrição Gênica , Células Cultivadas , Éxons/genética , Células HeLa , Humanos , Isoenzimas/genética , Isoenzimas/metabolismo , Proto-Oncogene Mas , Proto-Oncogenes/genética , Receptores Proteína Tirosina Quinases/metabolismo , Fatores de Processamento de Serina-Arginina
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