RESUMEN
Many microRNAs (miRNAs) are expressed with high spatiotemporal specificity during organismal development, with some being limited to rare cell types, often embedded in complex tissues. Yet, most miRNA profiling efforts remain at the tissue and organ levels. To overcome challenges in accessing the microRNomes from tissue-embedded cells, we had previously developed mime-seq (miRNome by methylation-dependent sequencing), a technique in which cell-specific miRNA methylation in C. elegans and Drosophila enabled chemo-selective sequencing without the need for cell sorting or biochemical purification. Here, we present mime-seq 2.0 for profiling miRNAs from specific mouse cell types. We engineered a chimeric RNA methyltransferase that is tethered to Argonaute protein and efficiently methylates miRNAs at their 3'-terminal 2'-OH in mouse and human cell lines. We also generated a transgenic mouse for conditional expression of this methyltransferase, which can be used to direct methylation of miRNAs in a cell type of choice. We validated the use of this mouse model by profiling miRNAs from B cells and bone marrow plasma cells.
Asunto(s)
MicroARNs , Animales , MicroARNs/genética , MicroARNs/metabolismo , Ratones , Humanos , Ratones Transgénicos , Metilación , Proteínas Argonautas/genética , Proteínas Argonautas/metabolismo , Análisis de Secuencia de ARN/métodos , Metiltransferasas/genética , Metiltransferasas/metabolismo , Línea Celular , Linfocitos B/metabolismoRESUMEN
While extended loop extrusion across the entire Igh locus controls VH -DJH recombination, local regulatory sequences, such as the PAIR elements, may also activate VH gene recombination in pro-B-cells. Here, we show that PAIR-associated VH 8 genes contain a conserved putative regulatory element (V8E) in their downstream sequences. To investigate the function of PAIR4 and its V8.7E, we deleted 890 kb containing all 14 PAIRs in the Igh 5' region, which reduced distal VH gene recombination over a 100-kb distance on either side of the deletion. Reconstitution by insertion of PAIR4-V8.7E strongly activated distal VH gene recombination. PAIR4 alone resulted in lower induction of recombination, indicating that PAIR4 and V8.7E function as one regulatory unit. The pro-B-cell-specific activity of PAIR4 depends on CTCF, as mutation of its CTCF-binding site led to sustained PAIR4 activity in pre-B and immature B-cells and to PAIR4 activation in T-cells. Notably, insertion of V8.8E was sufficient to activate VH gene recombination. Hence, enhancers of the PAIR4-V8.7E module and V8.8E element activate distal VH gene recombination and thus contribute to the diversification of the BCR repertoire in the context of loop extrusion.
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Células Precursoras de Linfocitos B , Secuencias Reguladoras de Ácidos Nucleicos , Secuencias Reguladoras de Ácidos Nucleicos/genética , Sitios de Unión , Recombinación GenéticaRESUMEN
Nuclear processes, such as V(D)J recombination, are orchestrated by the three-dimensional organization of chromosomes at multiple levels, including compartments1 and topologically associated domains (TADs)2,3 consisting of chromatin loops4. TADs are formed by chromatin-loop extrusion5-7, which depends on the loop-extrusion function of the ring-shaped cohesin complex8-12. Conversely, the cohesin-release factor Wapl13,14 restricts loop extension10,15. The generation of a diverse antibody repertoire, providing humoral immunity to pathogens, requires the participation of all V genes in V(D)J recombination16, which depends on contraction of the 2.8-Mb-long immunoglobulin heavy chain (Igh) locus by Pax517,18. However, how Pax5 controls Igh contraction in pro-B cells remains unknown. Here we demonstrate that locus contraction is caused by loop extrusion across the entire Igh locus. Notably, the expression of Wapl is repressed by Pax5 specifically in pro-B and pre-B cells, facilitating extended loop extrusion by increasing the residence time of cohesin on chromatin. Pax5 mediates the transcriptional repression of Wapl through a single Pax5-binding site by recruiting the polycomb repressive complex 2 to induce bivalent chromatin at the Wapl promoter. Reduced Wapl expression causes global alterations in the chromosome architecture, indicating that the potential to recombine all V genes entails structural changes of the entire genome in pro-B cells.
Asunto(s)
Genes de las Cadenas Pesadas de las Inmunoglobulinas/genética , Cadenas Pesadas de Inmunoglobulina/genética , Región Variable de Inmunoglobulina/genética , Factor de Transcripción PAX5/metabolismo , Proteínas/genética , Proteínas Represoras/metabolismo , Recombinación V(D)J/genética , Animales , Linfocitos B/citología , Linfocitos B/metabolismo , Sitios de Unión , Proteínas de Ciclo Celular/metabolismo , Ensamble y Desensamble de Cromatina , Proteínas Cromosómicas no Histona/metabolismo , Cadenas Pesadas de Inmunoglobulina/química , Región Variable de Inmunoglobulina/química , Ratones , Complejo Represivo Polycomb 2/metabolismo , Células Precursoras de Linfocitos B/citología , Células Precursoras de Linfocitos B/metabolismo , Regiones Promotoras Genéticas/genética , CohesinasRESUMEN
Rechargeable lithium-ion batteries are integral to contemporary energy storage, yet current anode material systems struggle to meet the increasing demand for extended range capabilities. This work introduces a novel composite anode material composed of one-dimensional 2H-phase tin disulfide (SnS2) nanoribbons enclosed within cavities of single-walled carbon nanotubes (SnS2@SWCNTs), achieved through precise atomic engineering. Employing aberration-corrected transmission electron microscopy, we precisely elucidated the crystal structure of SnS2 within the confines of the SWCNTs. This deliberate design effectively addresses the inherent limitations of SnS2 as a lithium-ion anode material, including its low electrical conductivity, considerable volume expansion effects, and unstable solid electrolyte interface membrane. Testing confirmed that SnS2 transforms into the Li5Sn2 alloy phase after full lithiation and back to SnS2 after delithiation, showing excellent reversibility. The composite also benefits from edge effects, improving lithium storage through stronger binding and lower migration barriers, which were supported by calculations. This pioneering work advances high-performance anode materials for applications.
RESUMEN
A high-fat diet (HFD) plays a critical role in hepatocyte insulin resistance. Numerous models and factors have been proposed to elucidate the mechanism of palmitic acid (PA)-induced insulin resistance. However, proteomic studies of insulin resistance by HFD stimulation are usually performed under insulin conditions, leading to an unclear understanding of how a HFD alone affects hepatocytes. Here, we mapped the phosphorylation rewiring events in PA-stimulated HepG2 cells and found PA decreased the phosphorylation level of the eukaryotic translation initiation factor 4E-binding protein 2 (4EBP2) at S65/T70. Further experiments identified 4EBP2 as a key node of insulin resistance in either HFD mice or PA-treated cells. Reduced 4EBP2 levels increased glucose uptake and insulin sensitivity, whereas the 4EBP2_S65A/T70A mutation exacerbated PA-induced insulin resistance. Additionally, the nascent proteome revealed many glycolysis-related proteins translationally regulated by 4EBP2 such as hexokinase-2, pyruvate kinase PKM, TBC1 domain family member 4, and glucose-6-phosphate 1-dehydrogenase. In summary, we report the critical role of 4EBP2 in regulating HFD-stimulated insulin resistance in hepatocytes.
Asunto(s)
Resistencia a la Insulina , Animales , Masculino , Ratones , Proteínas Portadoras/metabolismo , Línea Celular , Dieta Alta en Grasa/efectos adversos , Hepatocitos/metabolismo , Insulina/metabolismo , Resistencia a la Insulina/fisiología , Ratones Endogámicos C57BL , Ácido Palmítico/metabolismo , Biosíntesis de Proteínas , ProteómicaRESUMEN
Concrescence is a rare dental anomaly in which two adjacent teeth are united only by their cementum. Concrescence most frequently occurs in molars, especially a third mandibular molar and a supernumerary tooth. It is rarely seen in the maxillary anterior teeth. This case report is the first in the literature which details the successful treatment of a concrescence between the maxillary central incisor and a supernumerary tooth through multidisciplinary therapy. The treatment plan included root canal treatment, endodontic microsurgery, and prosthodontic treatment.
Asunto(s)
Microcirugia , Tratamiento del Conducto Radicular , Humanos , Microcirugia/métodos , Tratamiento del Conducto Radicular/métodos , Incisivo/anomalías , Incisivo/cirugía , Diente Supernumerario/cirugía , Diente Supernumerario/diagnóstico por imagen , Masculino , Femenino , AdultoRESUMEN
The further development of aqueous zinc (Zn)-ion batteries (AZIBs) is constrained by the high freezing points and the instability on Zn anodes. Current improvement strategies mainly focus on regulating hydrogen bond (HB) donors (H) of solvent water to disrupt HBs, while neglecting the environment of HB-acceptors (O). Herein, we propose a mechanism of chaotropic cation-regulated HB-acceptor via a "super hydrous solvated" structure. Chaotropic Ca2+ can form a solvated structure via competitively binding O atoms in H2O, effectively breaking the HBs among H2O molecules, thereby reducing the glass transition temperature of hybrid 1â mol L-1 (M) ZnCl2+4â M CaCl2 electrolyte (-113.2 °C). Meanwhile, the high hydratability of Ca2+ contributes to the water-poor solvated structure of Zn2+, suppressing side reactions and uneven Zn deposition. Benefiting from the anti-freezing electrolyte and high reversible Zn anode, the Zn||Pyrene-4,5,9,10-tetraone (PTO) batteries deliver an ultrahigh capacity of 183.9â mAh g-1 at 1.0â A g-1 over 1600-time stable cycling at -60 °C. This work presents a cheap and efficient aqueous electrolyte to simultaneously improve low-temperature performances and Zn stability, broadening the design concepts for antifreeze electrolytes.
RESUMEN
Zn metal suffers from severe zinc dendrites, anion-related side reactions, hydrogen evolution reaction (HER) and narrow electrochemical stable window (ESW). Herein, an"anions-in-colloid" hydrated deep eutectic electrolyte (ACDE-3) is designed to improve the stability of zinc anode. The ACDE-3 reconfigures the hydrogen-bond (HB) network and regulates the solvation shell. More importantly, the hydroxyl-rich ß-cyclodextrins (ß-CDs) in ACDE-3 self-assemble into micelles, in which the steric effect between the adjacent ß-CDs restricts the movement of anions. This unique "anions-in-colloid" structure enables the eutectic system with a high Zn2+ transference number (tZn2+) of 0.84. Thus, ACDE-3 inhibits the formation of dendrite, prevents the anion-involved side reactions, suppresses the HER, and enlarges the ESW to 2.32 V. The Zn//Zn symmetric cell delivers a long lifespan of 900 hours at 0.5 mAh cm-2, and the Zn//Cu half cells have a high average columbic efficiency (ACE) of 97.9% at 0.5 mAh cm-2 with a uniform and compact zinc deposition. When matched with a poly(1,5-naphthalenediamine) cathode, the full battery with a low negative/positive capacity ratio of 2 can still cycle steadily for 200 cycles at a current density of 1.0 A g-1. Additionally, this electrolyte can operative over a wide temperature range from -40 °C to 40 °C.
RESUMEN
Despite carbonate electrolytes exhibiting good stability to sulfurized polyacrylonitrile (SPAN), their chemical incompatibility with lithium (Li) metal anode leads to poor electrochemical performance of Li||SPAN full cells. While the SPAN employs conventional ether electrolytes that suffer from the shuttle effect, leading to rapid capacity fading. Here, we tailor a dilute electrolyte based on a low solvating power ether solvent that is both compatible with SPAN and Li metal. Unlike conventional ether electrolytes, the weakly solvating ether electrolyte enables SPAN to undergo reversibly "solid-solid" conversion. It features an anion-rich solvation structure that allows for the formation of a robust cathode electrolyte interphase on the SPAN, effectively blocking the dissolution of polysulfides into the bulk electrolyte and avoiding the shuttle effect. What's more, the unique electrolyte chemistry endowed Li ions with fast electroplating kinetics and induced high reversibility Li deposition/stripping process from 25 °C to -40 °C. Based on tailored electrolyte, Li||SPAN full cells matched with high loading SPAN cathodes (≈3.6â mAh cm-2 ) and 50â µm Li foil can operate stably over a wide range of temperatures. Additionally, Li||SPAN pouch cell under lean electrolyte and 5 % excess Li conditions can continuously operate stably for over a month.
RESUMEN
Kynureninase (KYNU) is a key enzyme in the tryptophan metabolism pathway with elevated expression in psoriatic lesions relative to normal skin. However, whether KYNU contributes to the pathogenesis of psoriasis remains unknown. We sought to investigate the role of KYNU in psoriasis and its possible regulation mechanism. In the results, KYNU is upregulated in psoriatic skin samples from patients or animal models compared with normal skin control which was assayed in psoriatic patient samples, IMQ-induced psoriasis-like skin inflammation in BABL/c mice and M5-stimulated keratinocyte cell lines by immunohistochemistry (IHC). KYNU knockdown had a trivial impact on keratinocyte proliferation, but significantly inhibited the production of inflammatory cytokines in HaCaT, HEKα, and HEKn cells by quantitative reverse-transcription polymerase chain reaction, enzyme-linked immunosorbent assay, and western blot analysis. The 3'-untranslated region of KYNU contains a conserved target site of a skin-specific microRNA (miRNA), miR-203a, as predicted by TargetScan software. Furthermore, miR-203a exhibited an inversed expression kinetics to KYNU during the development of IMQ-induced psoriasis-like skin inflammation in BABL/c mice. Overexpression of miR-203 subsequently leading to the inhibition of KYNU, could significantly reduce the production of M5-induced, psoriasis-related inflammatory factors in keratinocytes. Finally, KYNU inhibitors could alleviate the pathological phenotypes in IMQ-mice. Our study supported the contributive role of KYNU in the development of psoriasis and provided preliminary evidence for KYNU as a potential therapeutic target in psoriasis.
Asunto(s)
MicroARNs , Psoriasis , Animales , Proliferación Celular/genética , Humanos , Hidrolasas , Imiquimod/efectos adversos , Inflamación/metabolismo , Queratinocitos/metabolismo , Ratones , MicroARNs/metabolismo , Psoriasis/inducido químicamente , Psoriasis/tratamiento farmacológico , Psoriasis/genética , Piel/metabolismoRESUMEN
The immunoglobulin heavy-chain (Igh) locus undergoes large-scale contraction in pro-B cells, which facilitates VH-DJH recombination by juxtaposing distal VH genes next to the DJH-rearranged gene segment in the 3' proximal Igh domain. By using high-resolution mapping of long-range interactions, we demonstrate that local interaction domains established the three-dimensional structure of the extended Igh locus in lymphoid progenitors. In pro-B cells, these local domains engaged in long-range interactions across the Igh locus, which depend on the regulators Pax5, YY1, and CTCF. The large VH gene cluster underwent flexible long-range interactions with the more rigidly structured proximal domain, which probably ensures similar participation of all VH genes in VH-DJH recombination to generate a diverse antibody repertoire. These long-range interactions appear to be an intrinsic feature of the VH gene cluster, because they are still generated upon mutation of the Eµ enhancer, IGCR1 insulator, or 3' regulatory region in the proximal Igh domain.
Asunto(s)
Diversidad de Anticuerpos/genética , Reordenamiento Génico de Cadena Pesada de Linfocito B/genética , Genes de las Cadenas Pesadas de las Inmunoglobulinas , Región Variable de Inmunoglobulina/genética , Células Precursoras de Linfocitos B/inmunología , Animales , Secuencia de Bases , Sitios de Unión , Factor de Unión a CCCTC , Mapeo Cromosómico , Reordenamiento Génico , Ratones , Ratones Endogámicos C57BL , Factor de Transcripción PAX5/metabolismo , Unión Proteica , Proteínas Represoras/metabolismo , Análisis de Secuencia de ADN , Factor de Transcripción YY1/metabolismoRESUMEN
Recent studies have demonstrated that higher expression of follicular helper T cell (Tfh)-associated genes is associated with better prognosis in breast cancer and colorectal cancer (CRC), but the underlying mechanisms remain unclear. In this study, we compared the function of Tfh cells in non-cancer (NC) controls and in CRC patients between stages II and IV. Data showed that the level of CD4+CXCR5+ Tfh cells were significantly upregulated in stage II CRC patients but was progressively reduced in stage III and stage IV patients. The frequency of PD-1+ cells in CD4+CXCR5+ Tfh cells, on the other hand, was progressively increased from NC patients to CRC patients with increasing severity. Interestingly, the CD4+CXCR5+PD-1- Tfh cells, but not the CD4+CXCR5+PD-1+ Tfh cells, promoted the CD107a expression and IFN-γ expression by CD8+ T cells. This CD8+ T cell-promoting capacity was dependent on the expression of IL-21, as this capacity was significantly impaired by IL-21 neutralization. Tfh cells from CRC patients with advanced stages presented gradual reduction in the capacity to stimulate CD8+ T cells and the capacity to produce IL-21. In addition, treatment with autologous PD-L1-expressing tumor cells further suppressed the IL-21 expression by PD-1+ Tfh cells. Together, these data demonstrated that Tfh cells potently enhanced the effector functions of CD8+ T cells in an IL-21-dependent pathway; however, this role of Tfh cells was limited in CRC patients due to PD-1/PD-L1-mediated suppression.
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Antígeno B7-H1/genética , Neoplasias Colorrectales/genética , Regulación Neoplásica de la Expresión Génica , Interleucinas/genética , Receptor de Muerte Celular Programada 1/genética , Linfocitos T Citotóxicos/inmunología , Linfocitos T Colaboradores-Inductores/inmunología , Adolescente , Adulto , Anciano , Antígeno B7-H1/inmunología , Estudios de Casos y Controles , Neoplasias Colorrectales/inmunología , Neoplasias Colorrectales/patología , Femenino , Humanos , Inmunofenotipificación , Interferón gamma/genética , Interferón gamma/inmunología , Interleucinas/inmunología , Proteína 1 de la Membrana Asociada a los Lisosomas/genética , Proteína 1 de la Membrana Asociada a los Lisosomas/inmunología , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Receptor de Muerte Celular Programada 1/inmunología , Receptores CXCR5/genética , Receptores CXCR5/inmunología , Transducción de Señal , Linfocitos T Citotóxicos/patología , Linfocitos T Colaboradores-Inductores/patologíaRESUMEN
Pax5 is an essential regulator of B cell identity and function. Here, we used transgenesis and deletion mapping to identify a potent enhancer in intron 5 of the Pax5 locus. This enhancer in combination with the promoter region was sufficient to recapitulate the B lymphoid expression of Pax5. The enhancer was silenced by DNA methylation in embryonic stem cells, but became activated in multipotent hematopoietic progenitors. It contained functional binding sites for the transcription factors PU.1, IRF4, IRF8, and NF-kappaB, suggesting that these regulators contribute to sequential enhancer activation in hematopoietic progenitors and during B cell development. In contrast, the promoter region was repressed by Polycomb group proteins in non-B cells and was activated only at the onset of pro-B cell development through induction of chromatin remodeling by the transcription factor EBF1. These experiments demonstrate a stepwise activation of Pax5 in early lymphopoiesis and provide mechanistic insights into the process of B cell commitment.
Asunto(s)
Linfocitos B/inmunología , Elementos de Facilitación Genéticos , Regulación de la Expresión Génica , Linfopoyesis/fisiología , Factor de Transcripción PAX5 , Regiones Promotoras Genéticas , Transgenes/genética , Animales , Linfocitos B/citología , Secuencia de Bases , Cromosomas Artificiales Bacterianos/genética , Citometría de Flujo , Humanos , Ratones , Datos de Secuencia Molecular , Factor de Transcripción PAX5/genética , Factor de Transcripción PAX5/metabolismo , Transactivadores/genética , Regulación hacia ArribaRESUMEN
The transcription factor E2A controls the initiation of B lymphopoiesis, which is arrested at the pre-pro-B cell stage in E2A-deficient mice. Here, we demonstrate by conditional mutagenesis that E2A is essential for the development of pro-B, pre-B, and immature B cells in the bone marrow. E2A is, however, dispensable for the generation of mature B cells and plasma cells in peripheral lymphoid organs. In contrast, germinal center B cell development is impaired in the absence of E2A despite normal AID expression and class-switch recombination. Molecular analysis revealed that E2A is required not only for initiating but also for maintaining the expression of Ebf1, Pax5, and the B cell gene program in pro-B cells. Notably, precocious Pax5 transcription from the Ikzf1 locus promotes pro-B cell development in E2A-deficient mice, demonstrating that ectopic Pax5 expression is sufficient to activate the B lymphoid transcription program in vivo in the absence of E2A.
Asunto(s)
Linfocitos B/citología , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Centro Germinal/inmunología , Factor de Transcripción Ikaros/metabolismo , Células Progenitoras Linfoides/citología , Linfopoyesis , Factor de Transcripción PAX5/metabolismo , Animales , Linfocitos B/inmunología , Linfocitos B/metabolismo , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Células de la Médula Ósea/citología , Línea Celular , Supervivencia Celular , Centro Germinal/metabolismo , Factor de Transcripción Ikaros/genética , Células Progenitoras Linfoides/metabolismo , Linfopoyesis/genética , Ratones , Ratones Endogámicos C57BL , Ratones Mutantes , Mutagénesis , Factor de Transcripción PAX5/genética , Células Plasmáticas/citología , Células Plasmáticas/inmunología , Células Plasmáticas/metabolismoRESUMEN
BACKGROUND/AIMS: The kidney plays a critical role in the control of blood pressure and its elevation in salt-induced hypertension. Mitochondrial dysfunction, especially in energy metabolism, has been associated with hypertension. Here, we aimed to investigate mitochondrial function and metabolic features in renal mitochondria of Dahl salt-sensitive (SS) rats to gain further insight into the relationship between mitochondrial metabolism and predisposition to hypertension. METHODS: In this study, SS rats fed low-salt (LS) or high-salt (HS) diets were used to investigate mitochondrial function and metabolism including mitochondrial enzyme activities, pyridine nucleotides, metabolites, and oxidative stress by biochemical analysis and gas chromatography-mass spectrometer (GC-MS). RESULTS: Significantly lower activity levels of fumarase, isocitrate dehydrogenase and succinyl-CoA synthetase were observed in renal mitochondria of SS rats compared with SS.13BN control rats fed LS diets. Intra-mitochondrial pyridine nucleotide content and mitochondrial metabolism were adversely affected in SS rats. In accordance with this, reduced ATP production, Δψm, and superoxide dismutase (SOD) activity were also observed in mitochondria of the renal medulla and cortex of SS rats. Moreover, ATP production was further impaired and oxidative stress was increased, confirming that the mitochondria of SS rats fed HS diets were dysfunctional compared to those of rats fed LS diets. CONCLUSIONS: Our data demonstrated that the renal mitochondria of SS rats exhibited complicated metabolic alteration and dysfunction in low-salt diets, and high-salt diets aggravated these dysfunctions. Thus, these results may be associated with renal dysfunction, which, in turn, would help in understanding the development of salt-sensitive hypertension.
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Dieta Hiposódica/efectos adversos , Hipertensión/inducido químicamente , Riñón/metabolismo , Mitocondrias/metabolismo , Cloruro de Sodio/farmacología , Animales , Hipertensión/fisiopatología , Riñón/fisiopatología , Riñón/ultraestructura , Ratas Endogámicas DahlRESUMEN
Colorectal cancer (CRC) is one of the most common cancers worldwide accounting for â¼9% of cancer-related deaths, 90% of which are due to metastasis resulting from resistance to chemotherapeutic agents. Hence, it is imperative to develop novel biomarkers of CRC. Insulin-induced gene 2 (INSIG2) has been previously reported to be a negative regulator of cholesterol synthesis and was recently identified as a putative-positive prognostic biomarker for colon and pancreatic cancer prognosis. Even though it has been suggested as a colon cancer biomarker and as an inhibitor of Bax-mediated apoptosis, the role of INSIG2 in CRC is elusive. We initially validated that INSIG2 is a gene with univariate-negative prognostic capacity to discriminate human colon cancer survivorship and that if present along with adenomatous polyposis coli (APC) gene mutations further decrease overall survival. Gain- and loss-of-function studies of INSIG2 showed that the gene product is responsible for inducing migration and invasion and maintenance of the mesenchymal phenotype in vitro and metastasis in vivo. Interestingly, loss of INSIG2 did not affect tumorigenic potential per se, but affected hepatic invasion in a xenograft assay. Our findings reinforce that INSIG2 is a novel colon cancer biomarker, and suggest, for the first time, an exclusive connection between INSIG2 and metastatic dissemination without any effect on tumorigenesis. © 2015 IUBMB Life, 68(1):65-71, 2016.
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Neoplasias Colorrectales/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Neoplasias Hepáticas/metabolismo , Proteínas de la Membrana/metabolismo , Animales , Células CACO-2 , Carcinogénesis/metabolismo , Neoplasias Colorrectales/mortalidad , Neoplasias Colorrectales/patología , Expresión Génica , Células HT29 , Humanos , Péptidos y Proteínas de Señalización Intracelular/genética , Estimación de Kaplan-Meier , Neoplasias Hepáticas/mortalidad , Neoplasias Hepáticas/secundario , Masculino , Proteínas de la Membrana/genética , Ratones Desnudos , Trasplante de Neoplasias , Modelos de Riesgos ProporcionalesRESUMEN
A novel "collaborative assembly" approach was reported for the synthesis of an siRNA delivery system via a combination of an electrostatically driven physical assembly and a facile click reaction-mediated chemical assembly, which showed various advantages of more safety, efficiency, and flexibility over the conventional approach that is only based on the physical assembly. This strategy remained a high cationic property of lipid-based complex for high siRNA loading capacity. The direct chemical modification of a model polyanion, hyaluronic acid (HA) on the cationic complex via click chemistry shielded the positive charge of complex without affecting the siRNA binding, which reduced the toxicity and enhanced the blood stability of the complex. In addition, the incorporated polyanion might be prefunctionalized, which endued the carrier with better biological characteristics such as long circulating or tumor targeting. We demonstrated that the obtained lipid-polymer hybrid nanoparticle (RSC-HA) using collaborative assembly presented greater in vivo stability in the blood for efficient tumor targeting than the physically assembled RSC/HA in which HA was physically adsorbed on the complex. After endocytosis into the cells, the protection of RSC-HA on siRNA turned off, while the release of siRNA induced by the intracellular signals for enhanced gene-silencing capacity. This combination of physical and chemical assemblies provides an efficient strategy for the exploitation of safe, stable, and functionalized siRNA delivery systems.
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Técnicas de Transferencia de Gen , Neoplasias Experimentales/genética , Neoplasias Experimentales/metabolismo , ARN Interferente Pequeño/administración & dosificación , ARN Interferente Pequeño/metabolismo , Animales , Línea Celular Tumoral , Silenciador del Gen/efectos de los fármacos , Humanos , Lípidos/química , Ratones , Estructura Molecular , Nanopartículas/química , Neoplasias Experimentales/patología , Polímeros/química , ARN Interferente Pequeño/química , ARN Interferente Pequeño/farmacología , RatasRESUMEN
Pax5 is a critical regulator of B-cell commitment. Here, we identified direct Pax5 target genes by streptavidin-mediated ChIP-chip analysis of pro-B cells expressing in vivo biotinylated Pax5. By binding to promoters and enhancers, Pax5 directly regulates the expression of multiple transcription factor, cell surface receptor and signal transducer genes. One of the newly identified enhancers was shown by transgenic analysis to confer Pax5-dependent B-cell-specific activity to the Nedd9 gene controlling B-cell trafficking. Profiling of histone modifications in Pax5-deficient and wild-type pro-B cells demonstrated that Pax5 induces active chromatin at activated target genes, while eliminating active chromatin at repressed genes in committed pro-B cells. Pax5 rapidly induces these chromatin and transcription changes by recruiting chromatin-remodelling, histone-modifying and basal transcription factor complexes to its target genes. These data provide novel insight into the regulatory network and epigenetic regulation, by which Pax5 controls B-cell commitment.
Asunto(s)
Subgrupos de Linfocitos B/citología , Subgrupos de Linfocitos B/metabolismo , Diferenciación Celular , Cromatina/metabolismo , Marcación de Gen , Factor de Transcripción PAX5/fisiología , Animales , Diferenciación Celular/genética , Línea Celular , Técnicas de Sustitución del Gen , Marcación de Gen/métodos , Ratones , Ratones Noqueados , Ratones Transgénicos , Factor de Transcripción PAX5/genética , Unión Proteica/genética , Transporte de Proteínas/genética , Transducción de Señal/genética , Células Madre/citología , Células Madre/metabolismoRESUMEN
Currently, digital transformation is having various impacts on enterprises around the world, including the green innovation. However, the current literature on the relationship between digitalization and green innovation in enterprises is scarce. What is the relationship between them, and whether heterogeneous environmental regulation has mediating effects, are questions that are worth exploring. Using a sample of listed manufacturing enterprises in China, this paper empirically tests the impact of digital transformation on enterprise green innovation. The results show that: (1) Digital transformation has a significant positive impact on green innovation, including green innovation output and green innovation capability. (2) Diverse environmental regulation may have mediating effects of digital transformation's influence on green innovation. (3) After a number of robustness tests, the conclusions are still valid. This paper can provide a reference for developing green development strategies for manufacturing enterprises.