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1.
Nat Immunol ; 24(7): 1188-1199, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37322178

RESUMEN

Spalt-like transcription factor 1 (SALL1) is a critical regulator of organogenesis and microglia identity. Here we demonstrate that disruption of a conserved microglia-specific super-enhancer interacting with the Sall1 promoter results in complete and specific loss of Sall1 expression in microglia. By determining the genomic binding sites of SALL1 and leveraging Sall1 enhancer knockout mice, we provide evidence for functional interactions between SALL1 and SMAD4 required for microglia-specific gene expression. SMAD4 binds directly to the Sall1 super-enhancer and is required for Sall1 expression, consistent with an evolutionarily conserved requirement of the TGFß and SMAD homologs Dpp and Mad for cell-specific expression of Spalt in the Drosophila wing. Unexpectedly, SALL1 in turn promotes binding and function of SMAD4 at microglia-specific enhancers while simultaneously suppressing binding of SMAD4 to enhancers of genes that become inappropriately activated in enhancer knockout microglia, thereby enforcing microglia-specific functions of the TGFß-SMAD signaling axis.


Asunto(s)
Microglía , Factores de Transcripción , Animales , Ratones , Sitios de Unión , ADN , Ratones Noqueados , Microglía/metabolismo , Regiones Promotoras Genéticas/genética , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Factor de Crecimiento Transformador beta/metabolismo
2.
Cell ; 173(7): 1796-1809.e17, 2018 06 14.
Artículo en Inglés | MEDLINE | ID: mdl-29779944

RESUMEN

Non-coding genetic variation is a major driver of phenotypic diversity and allows the investigation of mechanisms that control gene expression. Here, we systematically investigated the effects of >50 million variations from five strains of mice on mRNA, nascent transcription, transcription start sites, and transcription factor binding in resting and activated macrophages. We observed substantial differences associated with distinct molecular pathways. Evaluating genetic variation provided evidence for roles of ∼100 TFs in shaping lineage-determining factor binding. Unexpectedly, a substantial fraction of strain-specific factor binding could not be explained by local mutations. Integration of genomic features with chromatin interaction data provided evidence for hundreds of connected cis-regulatory domains associated with differences in transcription factor binding and gene expression. This system and the >250 datasets establish a substantial new resource for investigation of how genetic variation affects cellular phenotypes.


Asunto(s)
Variación Genética , Macrófagos/metabolismo , Factores de Transcripción/metabolismo , Animales , Sitios de Unión , Células de la Médula Ósea/citología , Proteína beta Potenciadora de Unión a CCAAT/genética , Proteína beta Potenciadora de Unión a CCAAT/metabolismo , Análisis por Conglomerados , Elementos de Facilitación Genéticos/genética , Femenino , Regulación de la Expresión Génica/efectos de los fármacos , Lipopolisacáridos/farmacología , Macrófagos/citología , Macrófagos/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Endogámicos NOD , Regiones Promotoras Genéticas , Unión Proteica , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas/metabolismo , Transactivadores/genética , Transactivadores/metabolismo , Factores de Transcripción/genética
3.
Mol Cell ; 84(9): 1742-1752.e5, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38513661

RESUMEN

Histone H3 lysine 4 mono-methylation (H3K4me1) marks poised or active enhancers. KMT2C (MLL3) and KMT2D (MLL4) catalyze H3K4me1, but their histone methyltransferase activities are largely dispensable for transcription during early embryogenesis in mammals. To better understand the role of H3K4me1 in enhancer function, we analyze dynamic enhancer-promoter (E-P) interactions and gene expression during neural differentiation of the mouse embryonic stem cells. We found that KMT2C/D catalytic activities were only required for H3K4me1 and E-P contacts at a subset of candidate enhancers, induced upon neural differentiation. By contrast, a majority of enhancers retained H3K4me1 in KMT2C/D catalytic mutant cells. Surprisingly, H3K4me1 signals at these KMT2C/D-independent sites were reduced after acute depletion of KMT2B, resulting in aggravated transcriptional defects. Our observations therefore implicate KMT2B in the catalysis of H3K4me1 at enhancers and provide additional support for an active role of H3K4me1 in enhancer-promoter interactions and transcription in mammalian cells.


Asunto(s)
Diferenciación Celular , Elementos de Facilitación Genéticos , N-Metiltransferasa de Histona-Lisina , Histonas , Lisina/análogos & derivados , Células Madre Embrionarias de Ratones , Regiones Promotoras Genéticas , Animales , Ratones , Histonas/metabolismo , Histonas/genética , N-Metiltransferasa de Histona-Lisina/genética , N-Metiltransferasa de Histona-Lisina/metabolismo , Células Madre Embrionarias de Ratones/metabolismo , Células Madre Embrionarias de Ratones/citología , Activación Transcripcional , Metilación , Regulación del Desarrollo de la Expresión Génica , Proteína de la Leucemia Mieloide-Linfoide/metabolismo , Proteína de la Leucemia Mieloide-Linfoide/genética , Proteínas de Unión al ADN/metabolismo , Proteínas de Unión al ADN/genética
4.
Cell ; 150(3): 549-62, 2012 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-22863008

RESUMEN

Heat-Shock Factor 1 (HSF1), master regulator of the heat-shock response, facilitates malignant transformation, cancer cell survival, and proliferation in model systems. The common assumption is that these effects are mediated through regulation of heat-shock protein (HSP) expression. However, the transcriptional network that HSF1 coordinates directly in malignancy and its relationship to the heat-shock response have never been defined. By comparing cells with high and low malignant potential alongside their nontransformed counterparts, we identify an HSF1-regulated transcriptional program specific to highly malignant cells and distinct from heat shock. Cancer-specific genes in this program support oncogenic processes: cell-cycle regulation, signaling, metabolism, adhesion and translation. HSP genes are integral to this program, however, many are uniquely regulated in malignancy. This HSF1 cancer program is active in breast, colon and lung tumors isolated directly from human patients and is strongly associated with metastasis and death. Thus, HSF1 rewires the transcriptome in tumorigenesis, with prognostic and therapeutic implications.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Neoplasias/metabolismo , Factores de Transcripción/metabolismo , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Línea Celular Tumoral , Células Cultivadas , Proteínas de Unión al ADN/análisis , Proteínas de Unión al ADN/genética , Femenino , Regulación Neoplásica de la Expresión Génica , Redes Reguladoras de Genes , Genoma Humano , Factores de Transcripción del Choque Térmico , Humanos , Neoplasias/patología , Factores de Transcripción/análisis , Factores de Transcripción/genética
5.
Hum Mol Genet ; 33(20): 1789-1799, 2024 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-39126705

RESUMEN

Myotonic Dystrophy Type 1 (DM1) is an autosomal dominant multisystemic disorder for which cardiac features, including conduction delays and arrhythmias, are the second leading cause of disease mortality. DM1 is caused by expanded CTG repeats in the 3' untranslated region of the DMPK gene. Transcription of the expanded DMPK allele produces mRNAs containing long tracts of CUG repeats, which sequester the Muscleblind-Like family of RNA binding proteins, leading to their loss-of-function and the dysregulation of alternative splicing. A well-characterized mis-regulated splicing event in the DM1 heart is the increased inclusion of SCN5A exon 6A rather than the mutually exclusive exon 6B that normally predominates in adult heart. As previous work showed that forced inclusion of Scn5a exon 6A in mice recapitulates cardiac DM1 phenotypes, we tested whether rescue of Scn5a mis-splicing would improve the cardiac phenotypes in a DM1 heart mouse model. We generated mice lacking Scn5a exon 6A to force the expression of the adult SCN5A isoform including exon 6B and crossed these mice to our previously established CUG960 DM1 heart mouse model. We showed that correction Scn5a mis-splicing does not improve the DM1 heart conduction delays and structural changes induced by CUG repeat RNA expression. Interestingly, we found that in addition to Scn5a mis-splicing, Scn5a expression is reduced in heart tissues of CUG960 mice and DM1-affected individuals. These data indicate that Scn5a mis-splicing is not the sole driver of DM1 heart deficits and suggest a potential role for reduced Scn5a expression in DM1 cardiac disease.


Asunto(s)
Empalme Alternativo , Modelos Animales de Enfermedad , Exones , Distrofia Miotónica , Canal de Sodio Activado por Voltaje NAV1.5 , Animales , Canal de Sodio Activado por Voltaje NAV1.5/genética , Canal de Sodio Activado por Voltaje NAV1.5/metabolismo , Ratones , Distrofia Miotónica/genética , Distrofia Miotónica/patología , Distrofia Miotónica/metabolismo , Empalme Alternativo/genética , Exones/genética , Humanos , Miocardio/metabolismo , Miocardio/patología , Proteína Quinasa de Distrofia Miotónica/genética , Proteína Quinasa de Distrofia Miotónica/metabolismo , Corazón/fisiopatología , Empalme del ARN
6.
Plant J ; 118(2): 423-436, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38184843

RESUMEN

Upland cotton, the mainly cultivated cotton species in the world, provides over 90% of natural raw materials (fibers) for the textile industry. The development of cotton fibers that are unicellular and highly elongated trichomes on seeds is a delicate and complex process. However, the regulatory mechanism of fiber development is still largely unclear in detail. In this study, we report that a homeodomain-leucine zipper (HD-ZIP) IV transcription factor, GhHOX4, plays an important role in fiber elongation. Overexpression of GhHOX4 in cotton resulted in longer fibers, while GhHOX4-silenced transgenic cotton displayed a "shorter fiber" phenotype compared with wild type. GhHOX4 directly activates two target genes, GhEXLB1D and GhXTH2D, for promoting fiber elongation. On the other hand, phosphatidic acid (PA), which is associated with cell signaling and metabolism, interacts with GhHOX4 to hinder fiber elongation. The basic amino acids KR-R-R in START domain of GhHOX4 protein are essential for its binding to PA that could alter the nuclear localization of GhHOX4 protein, thereby suppressing the transcriptional regulation of GhHOX4 to downstream genes in the transition from fiber elongation to secondary cell wall (SCW) thickening during fiber development. Thus, our data revealed that GhHOX4 positively regulates fiber elongation, while PA may function in the phase transition from fiber elongation to SCW formation by negatively modulating GhHOX4 in cotton.


Asunto(s)
Gossypium , Factores de Transcripción , Gossypium/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Ácidos Fosfatidicos/metabolismo , Fibra de Algodón , Regulación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
7.
PLoS Pathog ; 19(4): e1011215, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-37036883

RESUMEN

Human papillomaviruses (HPVs) contribute to approximately 5% of all human cancers. Species-specific barriers limit the ability to study HPV pathogenesis in animal models. Murine papillomavirus (MmuPV1) provides a powerful tool to study the roles of papillomavirus genes in pathogenesis arising from a natural infection. We previously identified Protein Tyrosine Phosphatase Non-Receptor Type 14 (PTPN14), a tumor suppressor targeted by HPV E7 proteins, as a putative cellular target of MmuPV1 E7. Here, we confirmed the MmuPV1 E7-PTPN14 interaction. Based on the published structure of the HPV18 E7/PTPN14 complex, we generated a MmuPV1 E7 mutant, E7K81S, that was defective for binding PTPN14. Wild-type (WT) and E7K81S mutant viral genomes replicated as extrachromosomal circular DNAs to comparable levels in mouse keratinocytes. E7K81S mutant virus (E7K81S MmuPV1) was generated and used to infect FoxN/Nude mice. E7K81S MmuPV1 caused neoplastic lesions at a frequency similar to that of WT MmuPV1, but the lesions arose later and were smaller than WT-induced lesions. The E7K81S MmuPV1-induced lesions also had a trend towards a less severe grade of neoplastic disease. In the lesions, E7K81S MmuPV1 supported the late (productive) stage of the viral life cycle and promoted E2F activity and cellular DNA synthesis in suprabasal epithelial cells to similar degrees as WT MmuPV1. There was a similar frequency of lateral spread of infections among mice infected with E7K81S or WT MmuPV1. Compared to WT MmuPV1-induced lesions, E7K81S MmuPV1-induced lesions had a significant expansion of cells expressing differentiation markers, Keratin 10 and Involucrin. We conclude that an intact PTPN14 binding site is necessary for MmuPV1 E7's ability to contribute to papillomavirus-induced pathogenesis and this correlates with MmuPV1 E7 causing a delay in epithelial differentiation, which is a hallmark of papillomavirus-induced neoplasia.


Asunto(s)
Neoplasias , Proteínas Oncogénicas Virales , Infecciones por Papillomavirus , Enfermedades de la Piel , Animales , Humanos , Ratones , Diferenciación Celular , Ratones Desnudos , Proteínas Oncogénicas Virales/metabolismo , Papillomaviridae/genética , Proteínas E7 de Papillomavirus/genética , Proteínas E7 de Papillomavirus/metabolismo , Infecciones por Papillomavirus/genética , Unión Proteica , Proteínas Tirosina Fosfatasas no Receptoras/genética
8.
Nature ; 574(7779): 575-580, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31645732

RESUMEN

The Warburg effect, which originally described increased production of lactate in cancer, is associated with diverse cellular processes such as angiogenesis, hypoxia, polarization of macrophages and activation of T cells. This phenomenon is intimately linked to several diseases including neoplasia, sepsis and autoimmune diseases1,2. Lactate, which is converted from pyruvate in tumour cells, is widely known as an energy source and metabolic by-product. However, its non-metabolic functions in physiology and disease remain unknown. Here we show that lactate-derived lactylation of histone lysine residues serves as an epigenetic modification that directly stimulates gene transcription from chromatin. We identify 28 lactylation sites on core histones in human and mouse cells. Hypoxia and bacterial challenges induce the production of lactate by glycolysis, and this acts as a precursor that stimulates histone lactylation. Using M1 macrophages that have been exposed to bacteria as a model system, we show that histone lactylation has different temporal dynamics from acetylation. In the late phase of M1 macrophage polarization, increased histone lactylation induces homeostatic genes that are involved in wound healing, including Arg1. Collectively, our results suggest that an endogenous 'lactate clock' in bacterially challenged M1 macrophages turns on gene expression to promote homeostasis. Histone lactylation thus represents an opportunity to improve our understanding of the functions of lactate and its role in diverse pathophysiological conditions, including infection and cancer.


Asunto(s)
Epigénesis Genética , Glucólisis/genética , Histonas/química , Histonas/metabolismo , Ácido Láctico/metabolismo , Acetilación , Secuencia de Aminoácidos , Animales , Línea Celular Tumoral , Cromatina/química , Cromatina/genética , Cromatina/metabolismo , Homeostasis , Humanos , Hipoxia/metabolismo , Lisina/química , Lisina/metabolismo , Macrófagos/metabolismo , Macrófagos/microbiología , Masculino , Ratones , Ratones Endogámicos C57BL , Reproducibilidad de los Resultados , Transcripción Genética
9.
Nature ; 575(7784): 699-703, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31748743

RESUMEN

Oncogenes are commonly amplified on particles of extrachromosomal DNA (ecDNA) in cancer1,2, but our understanding of the structure of ecDNA and its effect on gene regulation is limited. Here, by integrating ultrastructural imaging, long-range optical mapping and computational analysis of whole-genome sequencing, we demonstrate the structure of circular ecDNA. Pan-cancer analyses reveal that oncogenes encoded on ecDNA are among the most highly expressed genes in the transcriptome of the tumours, linking increased copy number with high transcription levels. Quantitative assessment of the chromatin state reveals that although ecDNA is packaged into chromatin with intact domain structure, it lacks higher-order compaction that is typical of chromosomes and displays significantly enhanced chromatin accessibility. Furthermore, ecDNA is shown to have a significantly greater number of ultra-long-range interactions with active chromatin, which provides insight into how the structure of circular ecDNA affects oncogene function, and connects ecDNA biology with modern cancer genomics and epigenetics.


Asunto(s)
Cromatina/genética , ADN Circular/metabolismo , Regulación Neoplásica de la Expresión Génica/genética , Neoplasias/genética , Oncogenes/genética , Línea Celular Tumoral , Cromatina/química , ADN Circular/genética , Humanos , Microscopía Electrónica de Rastreo , Neoplasias/fisiopatología
10.
Mol Ther ; 32(3): 637-645, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38204163

RESUMEN

N-Acetylgalactosamine (GalNAc)-conjugated small interfering RNA (siRNA) therapies have received approval for treating both orphan and prevalent diseases. To improve in vivo efficacy and streamline the chemical synthesis process for efficient and cost-effective manufacturing, we conducted this study to identify better designs of GalNAc-siRNA conjugates for therapeutic development. Here, we present data on redesigned GalNAc-based ligands conjugated with siRNAs against angiopoietin-like 3 (ANGPTL3) and lipoprotein (a) (Lp(a)), two target molecules with the potential to address large unmet medical needs in atherosclerotic cardiovascular diseases. By attaching a novel pyran-derived scaffold to serial monovalent GalNAc units before solid-phase oligonucleotide synthesis, we achieved increased GalNAc-siRNA production efficiency with fewer synthesis steps compared to the standard triantennary GalNAc construct L96. The improved GalNAc-siRNA conjugates demonstrated equivalent or superior in vivo efficacy compared to triantennary GalNAc-conjugated siRNAs.


Asunto(s)
Enfermedades Cardiovasculares , Hepatocitos , Humanos , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/química , Análisis Costo-Beneficio , ARN Bicatenario , Acetilgalactosamina/química , Proteína 3 Similar a la Angiopoyetina
11.
Nucleic Acids Res ; 51(3): 1245-1259, 2023 02 22.
Artículo en Inglés | MEDLINE | ID: mdl-36617982

RESUMEN

Loss of gene function can be compensated by paralogs with redundant functions. An example of such compensation are the paralogs of the Muscleblind-Like (MBNL) family of RNA-binding proteins that are sequestered and lose their function in Myotonic Dystrophy Type 1 (DM1). Loss of MBNL1 increases the levels of its paralog MBNL2 in tissues where Mbnl2 expression is low, allowing MBNL2 to functionally compensate for MBNL1 loss. Here, we show that loss of MBNL1 increases the inclusion of Mbnl2 exon 6 and exon 9. We find that inclusion of Mbnl2 exon 6 increases the translocation of MBNL2 to the nucleus, while the inclusion of Mbnl2 exon 9 shifts the reading frame to an alternative C-terminus. We show that the C-terminus lacking exon 9 contains a PEST domain which causes proteasomal degradation. Loss of MBNL1 increases the inclusion of exon 9, resulting in an alternative C-terminus lacking the PEST domain and the increase of MBNL2. We further find that the compensatory mechanism is active in a mouse DM1 model. Together, this study uncovers the compensatory mechanism by which loss of MBNL1 upregulates its paralog MBNL2 and highlights a potential role of the compensatory mechanism in DM1.


Asunto(s)
Empalme Alternativo , Distrofia Miotónica , Proteínas de Unión al ARN , Animales , Ratones , Proteínas de Unión al ADN/genética , Exones , Distrofia Miotónica/genética , Proteínas de Unión al ARN/metabolismo , Activación Transcripcional , Regulación hacia Arriba
12.
Drug Resist Updat ; 76: 101112, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38924997

RESUMEN

AIMS: Despite aggressive treatment, the recurrence of glioma is an inevitable occurrence, leading to unsatisfactory clinical outcomes. A plausible explanation for this phenomenon is the phenotypic alterations that glioma cells undergo aggressive therapies, such as TMZ-therapy. However, the underlying mechanisms behind these changes are not well understood. METHODS: The TMZ chemotherapy resistance model was employed to assess the expression of intercellular adhesion molecule-1 (ICAM1) in both in vitro and in vivo settings. The potential role of ICAM1 in regulating TMZ chemotherapy resistance was investigated through knockout and overexpression techniques. Furthermore, the mechanism underlying ICAM1-mediated TMZ chemotherapy resistance was examined using diverse molecular biological methods, and the lipid raft protein was subsequently isolated to investigate the cellular subcomponents where ICAM1 operates. RESULTS: Acquired TMZ resistant (TMZ-R) glioma models heightened production of intercellular adhesion molecule-1 (ICAM1) in TMZ-R glioma cells. Additionally, we observed a significant suppression of TMZ-R glioma proliferation upon inhibition of ICAM1, which was attributed to the enhanced intracellular accumulation of TMZ. Our findings provide evidence supporting the role of ICAM1, a proinflammatory marker, in promoting the expression of ABCB1 on the cell membrane of TMZ-resistant cells. We have elucidated the mechanistic pathway by which ICAM1 modulates phosphorylated moesin, leading to an increase in ABCB1 expression on the membrane. Furthermore, our research has revealed that the regulation of moesin by ICAM1 was instrumental in facilitating the assembly of ABCB1 exclusively on the lipid raft of the membrane. CONCLUSIONS: Our findings suggest that ICAM1 is an important mediator in TMZ-resistant gliomas and targeting ICAM1 may provide a new strategy for enhancing the efficacy of TMZ therapy against glioma.


Asunto(s)
Subfamilia B de Transportador de Casetes de Unión a ATP , Neoplasias Encefálicas , Resistencia a Antineoplásicos , Glioma , Molécula 1 de Adhesión Intercelular , Temozolomida , Resistencia a Antineoplásicos/efectos de los fármacos , Glioma/tratamiento farmacológico , Glioma/patología , Glioma/genética , Glioma/metabolismo , Molécula 1 de Adhesión Intercelular/metabolismo , Molécula 1 de Adhesión Intercelular/genética , Humanos , Subfamilia B de Transportador de Casetes de Unión a ATP/metabolismo , Subfamilia B de Transportador de Casetes de Unión a ATP/genética , Temozolomida/farmacología , Línea Celular Tumoral , Animales , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/genética , Antineoplásicos Alquilantes/farmacología , Antineoplásicos Alquilantes/uso terapéutico , Proliferación Celular/efectos de los fármacos , Ratones , Microdominios de Membrana/metabolismo , Microdominios de Membrana/efectos de los fármacos
13.
Drug Resist Updat ; 76: 101113, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39053384

RESUMEN

Gliomas, the most common CNS (central nerve system) tumors, face poor survival due to severe chemoresistance exacerbated by hypoxia. However, studies on whether altered hypoxic conditions benefit for chemo-sensitivity and how gliomas react to increased oxygen stimulation are limited. In this study, we demonstrated that increased oxygen stimulation promotes glioma growth and chemoresistance. Mechanically, increased oxygen stimulation upregulates miR-1290 levels. miR-1290, in turn, downregulates PLCB1, while PLCB1 facilitates the proteasomal degradation of ß-catenin and active-ß-catenin by increasing the proportion of ubiquitinated ß-catenin in a destruction complex-independent mechanism. This process inhibits PLCB1 expression, leads to the accumulation of active-ß-catenin, boosting Wnt signaling through an independent mechanism and ultimately promoting chemoresistance in glioma cells. Pharmacological inhibition of Wnt by WNT974 could partially inhibit glioma volume growth and prolong the shortened survival caused by increased oxygen stimulation in a glioma-bearing mouse model. Moreover, PLCB1, a key molecule regulated by increased oxygen stimulation, shows promising predictive power in survival analysis and has great potential to be a biomarker for grading and prognosis in glioma patients. These results provide preliminary insights into clinical scenarios associated with altered hypoxic conditions in gliomas, and introduce a novel perspective on the role of the hypoxic microenvironment in glioma progression. Furthermore, the outcomes reveal the potential risks of utilizing hyperbaric oxygen treatment (HBOT) in glioma patients, particularly when considering HBOT as a standalone option to ameliorate neuro-dysfunctions or when combining HBOT with a single chemotherapy agent without radiotherapy.


Asunto(s)
Neoplasias Encefálicas , Resistencia a Antineoplásicos , Glioma , MicroARNs , Oxígeno , Fosfolipasa C beta , Vía de Señalización Wnt , beta Catenina , Glioma/tratamiento farmacológico , Glioma/patología , Glioma/genética , Glioma/terapia , Glioma/metabolismo , Animales , Humanos , Resistencia a Antineoplásicos/efectos de los fármacos , Ratones , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/terapia , Vía de Señalización Wnt/efectos de los fármacos , Oxígeno/metabolismo , Fosfolipasa C beta/metabolismo , Fosfolipasa C beta/genética , beta Catenina/metabolismo , beta Catenina/genética , Línea Celular Tumoral , MicroARNs/genética , MicroARNs/metabolismo , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Fenotipo , Ratones Desnudos
14.
BMC Biol ; 22(1): 18, 2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38273256

RESUMEN

BACKGROUND: The underrepresentation of Hmong-Mien (HM) people in Asian genomic studies has hindered our comprehensive understanding of the full landscape of their evolutionary history and complex trait architecture. South China is a multi-ethnic region and indigenously settled by ethnolinguistically diverse HM, Austroasiatic (AA), Tai-Kadai (TK), Austronesian (AN), and Sino-Tibetan (ST) people, which is regarded as East Asia's initial cradle of biodiversity. However, previous fragmented genetic studies have only presented a fraction of the landscape of genetic diversity in this region, especially the lack of haplotype-based genomic resources. The deep characterization of demographic history and natural-selection-relevant genetic architecture of HM people was necessary. RESULTS: We reported one HM-specific genomic resource and comprehensively explored the fine-scale genetic structure and adaptative features inferred from the genome-wide SNP data of 440 HM individuals from 33 ethnolinguistic populations, including previously unreported She. We identified solid genetic differentiation between HM people and Han Chinese at 7.64‒15.86 years ago (kya) and split events between southern Chinese inland (Miao/Yao) and coastal (She) HM people in the middle Bronze Age period and the latter obtained more gene flow from Ancient Northern East Asians. Multiple admixture models further confirmed that extensive gene flow from surrounding ST, TK, and AN people entangled in forming the gene pool of Chinese coastal HM people. Genetic findings of isolated shared unique ancestral components based on the sharing alleles and haplotypes deconstructed that HM people from the Yungui Plateau carried the breadth of previously unknown genomic diversity. We identified a direct and recent genetic connection between Chinese inland and Southeast Asian HM people as they shared the most extended identity-by-descent fragments, supporting the long-distance migration hypothesis. Uniparental phylogenetic topology and network-based phylogenetic relationship reconstruction found ancient uniparental founding lineages in southwestern HM people. Finally, the population-specific biological adaptation study identified the shared and differentiated natural selection signatures among inland and coastal HM people associated with physical features and immune functions. The allele frequency spectrum of cancer susceptibility alleles and pharmacogenomic genes showed significant differences between HM and northern Chinese people. CONCLUSIONS: Our extensive genetic evidence combined with the historical documents supported the view that ancient HM people originated from the Yungui regions associated with ancient "Three-Miao tribes" descended from the ancient Daxi-Qujialing-Shijiahe people. Then, some have recently migrated rapidly to Southeast Asia, and some have migrated eastward and mixed respectively with Southeast Asian indigenes, Liangzhu-related coastal ancient populations, and incoming southward ST people. Generally, complex population migration, admixture, and adaptation history contributed to the complicated patterns of population structure of geographically diverse HM people.


Asunto(s)
Pueblos del Este de Asia , Genética de Población , Humanos , China , Genómica , Haplotipos , Filogenia
15.
Nano Lett ; 24(7): 2131-2141, 2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38227823

RESUMEN

Ischemia/reperfusion (IR)-induced acute lung injury (ALI) has a high mortality rate. Reactive oxygen species (ROS) play a crucial role in causing cellular damage and death in IR-induced ALI. In this work, we developed a biomimetic lung-targeting nanoparticle (PC@MB) as an antioxidative lung protector for treating IR-induced ALI. PC@MBs showed excellent ROS scavenging and Nrf2 activation properties, along with a lung-targeting function through autologous cell membrane coating. The PC@MBs exhibited an impressive antioxidative and pulmonary protective role via redox homeostasis recovery through Nrf2 and heme oxygenase-1 activation. PC@MBs could maintain cell viability by effectively scavenging the intracellular ROS and restoring the redox equilibrium in the lesion. In the IR mouse model, the PC@MBs preferentially accumulated in the lung and distinctly repaired the pneumonic damage. Our strategy has the potential to offer a promising therapeutic paradigm for treating IR-induced ALI through the incorporation of different therapeutic mechanisms.


Asunto(s)
Lesión Pulmonar Aguda , Daño por Reperfusión , Ratones , Animales , Antioxidantes/farmacología , Antioxidantes/uso terapéutico , Factor 2 Relacionado con NF-E2/metabolismo , Factor 2 Relacionado con NF-E2/farmacología , Factor 2 Relacionado con NF-E2/uso terapéutico , Especies Reactivas de Oxígeno/metabolismo , Biomimética , Lesión Pulmonar Aguda/tratamiento farmacológico , Pulmón/metabolismo , Daño por Reperfusión/tratamiento farmacológico , Isquemia , Reperfusión/efectos adversos , Estrés Oxidativo
16.
Nano Lett ; 24(21): 6296-6301, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38747343

RESUMEN

Ion transport through nanoporous two-dimensional (2D) membranes is predicted to be tunable by controlling the charging status of the membranes' planar surfaces, the behavior of which though remains to be assessed experimentally. Here we investigate ion transport through intrinsically porous membranes made of 2D metal-organic-framework layers. In the presence of certain cations, we observe a linear-to-nonlinear transition of the ionic current in response to the applied electric field, the behavior of which is analogous to the cation gating effect in the biological ion channels. Specifically, the ionic currents saturate at transmembrane voltages exceeding a few hundreds of millivolts, depending on the concentration of the gating cations. This is attributed to the binding of cations at the membranes' surfaces, tuning the charging states there and affecting the entry/exit process of translocating ions. Our work also provides 2D membranes as candidates for building nanofluidic devices with tunable transport properties.

17.
J Cell Sci ; 135(10)2022 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-35466366

RESUMEN

Tripeptidyl peptidase II (TPPII or TPP2) degrades N-terminal tripeptides from proteins and peptides. Studies in both humans and mice have shown that TPPII deficiency is linked to cellular immune-senescence, lifespan regulation and the aging process. However, the mechanism of how TPPII participates in these processes is less clear. In this study, we established a chemical probe-based assay and found that although the mRNA and protein levels of TPPII were not altered during senescence, its enzymatic activity was reduced in senescent human fibroblasts. We also showed that elevation of the levels of the serine protease inhibitor serpinB2 reduced TPPII activity in senescent cells. Moreover, suppression of TPPII led to elevation in the amount of lysosomal contents as in well as TPPI (TPP1) and ß-galactosidase activities, suggesting that lysosome biogenesis is induced to compensate for the reduction of TPPII activity in senescent cells. Together, this study discloses a critical role of the serpinB2-TPPII signaling pathway in proteostasis during senescence. Since serpinB2 levels can be increased by a variety of cellular stresses, reduction of TPPII activity through activation of serpinB2 might represent a common pathway for cells to respond to different stress conditions. This article has an associated First Person interview with the first author of the paper.


Asunto(s)
Aminopeptidasas , Senescencia Celular , Dipeptidil-Peptidasas y Tripeptidil-Peptidasas , Péptidos y Proteínas de Señalización Intracelular , Aminopeptidasas/genética , Aminopeptidasas/metabolismo , Senescencia Celular/genética , Senescencia Celular/fisiología , Dipeptidil-Peptidasas y Tripeptidil-Peptidasas/genética , Dipeptidil-Peptidasas y Tripeptidil-Peptidasas/metabolismo , Fibroblastos/metabolismo , Fibroblastos/fisiología , Humanos , Péptidos y Proteínas de Señalización Intracelular/genética , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Proteostasis/genética , Proteostasis/fisiología , Serina Endopeptidasas/metabolismo , Transducción de Señal
18.
Small ; 20(42): e2402676, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38847072

RESUMEN

Fluorescent lateral flow immunoassays (FLFIA) is a well-established rapid detection technique for quantitative analysis. However, achieving accurate analysis of biomarkers at the pg mL-1 level using FLFIA still poses challenges. Herein, an ultrasensitive FLFIA platform is reported utilizing a kiwi-type magneto-fluorescent silica nanohybrid (designated as MFS) that serves as both a target-enrichment substrate and an optical signal enhancement label. The spatially-layered architecture comprises a Fe3O4 core, an endocarp-fibers like dendritic mesoporous silica, seed-like quantum dots, and a kiwi-flesh like silica matrix. The MFS demonstrates heightened fluorescence brightness, swift magnetic response, excellent size uniformity, and dispersibility in water. Through liquid-phase capturing and fluorescence-enhanced signal amplification, as well as magnetic-enrichment sample amplification and magnetic-separation noise reduction, the MFS-based FLFIA is successfully applied to the detection of cardiac troponin I that achieved a limit of detection at 8.4 pg mL-1, tens of times lower than those of previously published fluorescent and colorimetric lateral flow immunoassays. This work offers insights into the strategic design of magneto-fluorescent synergetic signal amplification on LFIA platform and underscores their prospects in high-sensitive rapid and on-site diagnosis of biomarkers.


Asunto(s)
Dióxido de Silicio , Inmunoensayo/métodos , Dióxido de Silicio/química , Sistemas de Atención de Punto , Humanos , Troponina I/análisis , Troponina I/sangre , Puntos Cuánticos/química , Fluorescencia , Nanoestructuras/química , Magnetismo , Límite de Detección
19.
Am Heart J ; 278: 33-40, 2024 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-39182902

RESUMEN

BACKGROUND: Co-morbid hypertension is strong predictor of adverse cardiovascular (CV) outcomes in patients with atrial fibrillation (AF) but the optimal target for blood pressure (BP) control in this patient population has not been clearly defined. METHODS: The Cardiovascular Risk reduction in patients with Atrial Fibrillation Trial (CRAFT) is an investigator-initiated and conducted, international, multicenter, open-label, parallel-group, blinded outcome assessed, randomized controlled trial of intensive BP control in patients with AF. The aim is to determine whether intensive BP control (target home systolic blood pressure [SBP] <120 mmHg) is superior to standard BP control (home SBP <135 mmHg) on the hierarchical composite outcome of time to CV death, number of stroke events, time to the first stroke, number of myocardial infarction (MI) events, time to the first MI, number of heart failure hospitalization (HFH) events, and time to the first HFH. A sample size of 1,675 patients is estimated to provide 80% power to detect a win-ratio of 1.50 for intensive versus standard BP control on the primary composite outcome. Study visits are conducted at 1, 2, 3, and 6 months postrandomization, and every 6 months thereafter during the study. CONCLUSIONS: This clinical trial aims to provide reliable evidence of the effects of intensive BP control in patients with AF. TRIAL REGISTRATION: The trial is registered at ClinicalTrials.gov (NCT04347330).

20.
J Transl Med ; 22(1): 644, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38982507

RESUMEN

BACKGROUND: Genetic disorders often manifest as abnormal fetal or childhood development. Copy number variations (CNVs) represent a significant genetic mechanism underlying such disorders. Despite their importance, the effectiveness of clinical exome sequencing (CES) in detecting CNVs, particularly small ones, remains incompletely understood. We aimed to evaluate the detection of both large and small CNVs using CES in a substantial clinical cohort, including parent-offspring trios and proband only analysis. METHODS: We conducted a retrospective analysis of CES data from 2428 families, collected from 2018 to 2021. Detected CNV were categorized as large or small, and various validation techniques including chromosome microarray (CMA), Multiplex ligation-dependent probe amplification assay (MLPA), and/or PCR-based methods, were employed for cross-validation. RESULTS: Our CNV discovery pipeline identified 171 CNV events in 154 cases, resulting in an overall detection rate of 6.3%. Validation was performed on 113 CNVs from 103 cases to assess CES reliability. The overall concordance rate between CES and other validation methods was 88.49% (100/113). Specifically, CES demonstrated complete consistency in detecting large CNV. However, for small CNVs, consistency rates were 81.08% (30/37) for deletions and 73.91% (17/23) for duplications. CONCLUSION: CES demonstrated high sensitivity and reliability in CNV detection. It emerges as an economical and dependable option for the clinical CNV detection in cases of developmental abnormalities, especially fetal structural abnormalities.


Asunto(s)
Variaciones en el Número de Copia de ADN , Secuenciación del Exoma , Enfermedades Genéticas Congénitas , Humanos , Variaciones en el Número de Copia de ADN/genética , Enfermedades Genéticas Congénitas/diagnóstico , Enfermedades Genéticas Congénitas/genética , Reproducibilidad de los Resultados , Femenino , Valor Predictivo de las Pruebas , Masculino , Estudios Retrospectivos
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