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1.
Mol Cell ; 82(10): 1894-1908.e5, 2022 05 19.
Artículo en Inglés | MEDLINE | ID: mdl-35390275

RESUMEN

miR-10b is silenced in normal neuroglial cells of the brain but commonly activated in glioma, where it assumes an essential tumor-promoting role. We demonstrate that the entire miR-10b-hosting HOXD locus is activated in glioma via the cis-acting mechanism involving 3D chromatin reorganization and CTCF-cohesin-mediated looping. This mechanism requires two interacting lncRNAs, HOXD-AS2 and LINC01116, one associated with HOXD3/HOXD4/miR-10b promoter and another with the remote enhancer. Knockdown of either lncRNA in glioma cells alters CTCF and cohesin binding, abolishes chromatin looping, inhibits the expression of all genes within HOXD locus, and leads to glioma cell death. Conversely, in cortical astrocytes, enhancer activation is sufficient for HOXD/miR-10b locus reorganization, gene derepression, and neoplastic cell transformation. LINC01116 RNA is essential for this process. Our results demonstrate the interplay of two lncRNAs in the chromatin folding and concordant regulation of miR-10b and multiple HOXD genes normally silenced in astrocytes and triggering the neoplastic glial transformation.


Asunto(s)
Glioma , MicroARNs , ARN Largo no Codificante , Línea Celular Tumoral , Proliferación Celular/genética , Transformación Celular Neoplásica/genética , Cromatina/genética , Regulación Neoplásica de la Expresión Génica , Glioma/genética , Glioma/metabolismo , Humanos , MicroARNs/genética , MicroARNs/metabolismo , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo
2.
Brief Bioinform ; 24(1)2023 01 19.
Artículo en Inglés | MEDLINE | ID: mdl-36516300

RESUMEN

Effective full quantum mechanics (FQM) calculation of protein remains a grand challenge and of great interest in computational biology with substantial applications in drug discovery, protein dynamic simulation and protein folding. However, the huge computational complexity of the existing QM methods impends their applications in large systems. Here, we design a transfer-learning-based deep learning (TDL) protocol for effective FQM calculations (TDL-FQM) on proteins. By incorporating a transfer-learning algorithm into deep neural network (DNN), the TDL-FQM protocol is capable of performing calculations at any given accuracy using models trained from small datasets with high-precision and knowledge learned from large amount of low-level calculations. The high-level double-hybrid DFT functional and high-level quality of basis set is used in this work as a case study to evaluate the performance of TDL-FQM, where the selected 15 proteins are predicted to have a mean absolute error of 0.01 kcal/mol/atom for potential energy and an average root mean square error of 1.47 kcal/mol/$ {\rm A^{^{ \!\!\!o}}} $ for atomic forces. The proposed TDL-FQM approach accelerates the FQM calculation more than thirty thousand times faster in average and presents more significant benefits in efficiency as the size of protein increases. The ability to learn knowledge from one task to solve related problems demonstrates that the proposed TDL-FQM overcomes the limitation of standard DNN and has a strong power to predict proteins with high precision, which solves the challenge of high precision prediction in large chemical and biological systems.


Asunto(s)
Redes Neurales de la Computación , Proteínas , Proteínas/metabolismo , Algoritmos , Teoría Cuántica , Aprendizaje Automático
3.
Mol Psychiatry ; 28(11): 4877-4888, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37365243

RESUMEN

We previously reported that prolonged exposure to an enriched environment (EE) enhances hippocampal synaptic plasticity, with one of the significant mechanistic pathways being activation of ß2-adrenergic receptor (ß2-AR) signaling, thereby mitigating the synaptotoxic effects of soluble oligomers of amyloid ß-protein (oAß). However, the detailed mechanism remained elusive. In this work, we recorded field excitatory postsynaptic potentials (fEPSP) in the CA1 region of mouse hippocampal slices treated with or without toxic Aß-species. We found that pharmacological activation of ß2-AR, but not ß1-AR, selectively mimicked the effects of EE in enhancing LTP and preventing oAß-induced synaptic dysfunction. Mechanistic analyses showed that certain histone deacetylase (HDAC) inhibitors mimicked the benefits of EE, but this was not seen in ß2-AR knockout mice, suggesting that activating ß2-AR prevents oAß-mediated synaptic dysfunction via changes in histone acetylation. EE or activation of ß-ARs each decreased HDAC2, whereas Aß oligomers increased HDAC2 levels in the hippocampus. Further, oAß-induced inflammatory effects and neurite degeneration were prevented by either ß2-AR agonists or certain specific HDAC inhibitors. These preclinical results suggest that activation of ß2-AR is a novel potential therapeutic strategy to mitigate oAß-mediated features of AD.


Asunto(s)
Péptidos beta-Amiloides , Hipocampo , Ratones , Animales , Péptidos beta-Amiloides/toxicidad , Péptidos beta-Amiloides/metabolismo , Transducción de Señal , Epigénesis Genética , Ratones Noqueados
4.
Mol Biol Rep ; 51(1): 153, 2024 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-38236436

RESUMEN

BACKGROUND: Familial hypercholesterolemia (FH) is an autosomal dominant disease of lipid metabolism mainly caused by mutations in the low-density lipoprotein receptor (LDLR) gene. Genetic detection of patients with FH help with precise diagnosis and treatment, thus reducing the risk of coronary heart disease (CHD) and other related diseases. The study aimed to identify the causative gene mutations in a Chinese FH family and reveal the pathogenicity and the mechanism of these mutations. METHODS AND RESULTS: Whole exome sequencing was performed in a patient with severe lipid metabolism dysfunction seeking fertility guidance from a Chinese FH family. Two LDLR variants c.1875 C > G (p.N625K; novel variant) and c.1448G > A (p.W483*) were identified in the family. Wildtype and mutant LDLR constructs were established by the site-direct mutagenesis technique. Functional studies were carried out by cell transfection to evaluate the impact of detected variants on LDLR activity. The two variants were proven to affect LDL uptake and binding, resulting in cholesterol clearance reduction to different degrees. According to The American College of Medical Genetics and Genomics (ACMG) Standards and Guidelines, the W483* variant was classified as "Pathogenic", while the N625K variant as "VUS". CONCLUSIONS: Our results provide novel experimental evidence of functional alteration by LDLR variants identified in our study and expand the mutational spectrum of LDLR mutation induced FH.


Asunto(s)
Hiperlipoproteinemia Tipo II , Metabolismo de los Lípidos , Receptores de LDL , Humanos , Transporte Biológico , Hiperlipoproteinemia Tipo II/genética , Mutagénesis , Receptores de LDL/genética
5.
Brief Bioinform ; 22(2): 1225-1231, 2021 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-32942296

RESUMEN

The lack of a vaccine or any effective treatment for the aggressive novel coronavirus disease (COVID-19) has created a sense of urgency for the discovery of effective drugs. Several repurposing pharmaceutical candidates have been reported or envisaged to inhibit the emerging infections of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), but their binding sites, binding affinities and inhibitory mechanisms are still unavailable. In this study, we use the ligand-protein docking program and molecular dynamic simulation to ab initio investigate the binding mechanism and inhibitory ability of seven clinically approved drugs (Chloroquine, Hydroxychloroquine, Remdesivir, Ritonavir, Beclabuvir, Indinavir and Favipiravir) and a recently designed α-ketoamide inhibitor (13b) at the molecular level. The results suggest that Chloroquine has the strongest binding affinity with 3CL hydrolase (Mpro) among clinically approved drugs, indicating its effective inhibitory ability for SARS-CoV-2. However, the newly designed inhibitor 13b shows potentially improved inhibition efficiency with larger binding energy compared with Chloroquine. We further calculate the important binding site residues at the active site and demonstrate that the MET 165 and HIE 163 contribute the most for 13b, while the MET 165 and GLN 189 for Chloroquine, based on residual energy decomposition analysis. The proposed work offers a higher research priority for 13b to treat the infection of SARS-CoV-2 and provides theoretical basis for further design of effective drug molecules with stronger inhibition.


Asunto(s)
Antivirales/farmacología , COVID-19/virología , SARS-CoV-2/efectos de los fármacos , Antivirales/química , Diseño de Fármacos , Humanos , Ligandos , Simulación del Acoplamiento Molecular , SARS-CoV-2/metabolismo , Termodinámica , Proteínas Virales/metabolismo
6.
Brief Bioinform ; 22(6)2021 11 05.
Artículo en Inglés | MEDLINE | ID: mdl-34017993

RESUMEN

Full-quantum mechanics (QM) calculations are extraordinarily precise but difficult to apply to large systems, such as biomolecules. Motivated by the massive demand for efficient calculations for large systems at the full-QM level and by the significant advances in machine learning, we have designed a neural network-based two-body molecular fractionation with conjugate caps (NN-TMFCC) approach to accelerate the energy and atomic force calculations of proteins. The results show very high precision for the proposed NN potential energy surface models of residue-based fragments, with energy root-mean-squared errors (RMSEs) less than 1.0 kcal/mol and force RMSEs less than 1.3 kcal/mol/Å for both training and testing sets. The proposed NN-TMFCC method calculates the energies and atomic forces of 15 representative proteins with full-QM precision in 10-100 s, which is thousands of times faster than the full-QM calculations. The computational complexity of the NN-TMFCC method is independent of the protein size and only depends on the number of residue species, which makes this method particularly suitable for rapid prediction of large systems with tens of thousands or even hundreds of thousands of times acceleration. This highly precise and efficient NN-TMFCC approach exhibits considerable potential for performing energy and force calculations, structure predictions and molecular dynamics simulations of proteins with full-QM precision.


Asunto(s)
Aprendizaje Automático , Simulación de Dinámica Molecular , Redes Neurales de la Computación , Proteínas/química , Teoría Cuántica , Algoritmos , Biología Computacional/métodos , Bases de Datos de Proteínas , Péptidos , Conformación Proteica , Reproducibilidad de los Resultados
7.
Ecotoxicol Environ Saf ; 249: 114425, 2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38321695

RESUMEN

Available evidence suggest that exposure to PM2.5 during pregnancy is associated with reduced cognitive function in offspring. This study aimed to investigate the effects of maternal exposure to PM2.5 on offspring cognitive function and to elucidate the underlying mechanisms. In this work, pregnant C57BL/6 female mice were exposed to concentrated ambient PM2.5 or filtered air from day 0.5 (=vaginal plug) to day 15.5 in the Shanghai Meteorological and Environmental Animal Exposure System, and offspring cerebellar tissues were collected on embryonic day 15.5, as well as postnatal days 0, 10 and 42. The mean PM2.5 concentrations exposed to the pregnant mice were 73.06 ± 4.90 µg/m3 and 11.15 ± 2.71 µg/m3 in the concentrated ambient PM2.5 and filtered air chambers, respectively. Maternal concentrated PM2.5 exposure was negatively correlated with offspring spatial memory significantly as assessed by the Morris water maze. Compared with the filtered air group, PM2.5-exposed offspring mice had reduced cerebellar microglia. Both RNA and protein levels of IL-8 and TNF-α were elevated in the concentrated ambient PM2.5 group. PM2.5 exposure increased the level of 8-OHG in miRNA of microglia and Purkinje cells in 6-week-old offspring. The level of prostaglandin F2α (8-iso-PGF2Aα) in the cerebellum was increased at different growing stages of offspring after gestational exposure of PM2.5. These results suggested that maternal air pollution exposure might cause inflammatory damage and oxidative stress to the cerebellum, contributing to reduced cognitive performance in mice offspring.


Asunto(s)
Contaminantes Atmosféricos , Disfunción Cognitiva , Humanos , Embarazo , Femenino , Ratones , Animales , Exposición Materna , Material Particulado , Enfermedades Neuroinflamatorias , Ratones Endogámicos C57BL , China , Estrés Oxidativo , Cerebelo
8.
Molecules ; 28(11)2023 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-37298821

RESUMEN

Depression, a mental disorder that plagues the world, is a burden on many families. There is a great need for new, fast-acting antidepressants to be developed. N-methyl-D-aspartic acid (NMDA) is an ionotropic glutamate receptor that plays an important role in learning and memory processes and its TMD region is considered as a potential target to treat depression. However, due to the unclear binding sites and pathways, the mechanism of drug binding lacks basic explanation, which brings great complexity to the development of new drugs. In this study, we investigated the binding affinity and mechanisms of an FDA-approved antidepressant (S-ketamine) and seven potential antidepressants (R-ketamine, memantine, lanicemine, dextromethorphan, Ro 25-6981, ifenprodil, and traxoprodil) targeting the NMDA receptor by ligand-protein docking and molecular dynamics simulations. The results indicated that Ro 25-6981 has the strongest binding affinity to the TMD region of the NMDA receptor among the eight selected drugs, suggesting its potential effective inhibitory effect. We also calculated the critical binding-site residues at the active site and found that residues Leu124 and Met63 contributed the most to the binding energy by decomposing the free energy contributions on a per-residue basis. We further compared S-ketamine and its chiral molecule, R-ketamine, and found that R-ketamine had a stronger binding capacity to the NMDA receptor. This study provides a computational reference for the treatment of depression targeting NMDA receptors, and the proposed results will provide potential strategies for further antidepressant development and is a useful resource for the future discovery of fast-acting antidepressant candidates.


Asunto(s)
Antidepresivos , Receptores de N-Metil-D-Aspartato , Humanos , Antidepresivos/química , Receptores de N-Metil-D-Aspartato/antagonistas & inhibidores , Receptores de N-Metil-D-Aspartato/química , Unión Proteica , Simulación de Dinámica Molecular , Sitios de Unión , Ligandos , Conformación Proteica
9.
Mol Cancer ; 21(1): 17, 2022 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-35033060

RESUMEN

BACKGROUND: miRNAs are regulatory transcripts established as repressors of mRNA stability and translation that have been functionally implicated in carcinogenesis. miR-10b is one of the key onco-miRs associated with multiple forms of cancer. Malignant gliomas exhibit particularly striking dependence on miR-10b. However, despite the therapeutic potential of miR-10b targeting, this miRNA's poorly investigated and largely unconventional properties hamper the clinical translation. METHODS: We utilized Covalent Ligation of Endogenous Argonaute-bound RNAs and their high-throughput RNA sequencing to identify miR-10b interactome and a combination of biochemical and imaging approaches for target validation. They included Crosslinking and RNA immunoprecipitation with spliceosomal proteins, a combination of miRNA FISH with protein immunofluorescence in glioma cells and patient-derived tumors, native Northern blotting, and the transcriptome-wide analysis of alternative splicing. RESULTS: We demonstrate that miR-10b binds to U6 snRNA, a core component of the spliceosomal machinery. We provide evidence of the direct binding between miR-10b and U6, in situ imaging of miR-10b and U6 co-localization in glioma cells and tumors, and biochemical co-isolation of miR-10b with the components of the spliceosome. We further demonstrate that miR-10b modulates U6 N-6-adenosine methylation and pseudouridylation, U6 binding to splicing factors SART3 and PRPF8, and regulates U6 stability, conformation, and levels. These effects on U6 result in global splicing alterations, exemplified by the altered ratio of the isoforms of a small GTPase CDC42, reduced overall CDC42 levels, and downstream CDC42 -mediated effects on cell viability. CONCLUSIONS: We identified U6 snRNA, the key RNA component of the spliceosome, as the top miR-10b target in glioblastoma. We, therefore, present an unexpected intersection of the miRNA and splicing machineries and a new nuclear function for a major cancer-associated miRNA.


Asunto(s)
Núcleo Celular/genética , Regulación Neoplásica de la Expresión Génica , MicroARNs/genética , Oncogenes , Empalme del ARN , ARN Nuclear Pequeño/genética , Empalme Alternativo , Antígenos de Neoplasias/metabolismo , Línea Celular Tumoral , Humanos , Glicoproteínas de Membrana/genética , Modelos Biológicos , Interferencia de ARN , ARN Nuclear Pequeño/química , Proteínas de Unión al ARN/metabolismo , Receptores Inmunológicos/genética , Empalmosomas/metabolismo , Proteína de Unión al GTP cdc42/genética
10.
J Asian Nat Prod Res ; 24(8): 754-760, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34647847

RESUMEN

Quercetin (1) was converted into quercetin 7-O-succinyl glucoside (2) by used Bacillus amyloliquefaciens FJ18 as a solvent-resistant whole-cell biocatalyst. The structure of the new compound was confirmed by LC-MS analysis and NMR spectroscopy. The water-solubility of this novel quercetin 7-O-succinyl glucoside (2) was approximately 1000 times higher than that of native quercetin (2). Quercetin (1) and quercetin 7-O-succinyl glucoside (2) exhibited significant DPPH scavenging capacity with IC50 values of 23.55 and 36.05 µM, respectively. Both compounds showed moderate cytotoxic effects against the two human cancer cell lines (MCF-7 and HepG2) with IC50 values ranging from 39.45-63.38 µM.


Asunto(s)
Antioxidantes , Quercetina , Antioxidantes/farmacología , Glucósidos/química , Humanos , Estructura Molecular , Rutina , Agua
11.
Molecules ; 26(23)2021 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-34885762

RESUMEN

The long-acting parenteral formulation of the HIV integrase inhibitor cabotegravir (GSK744) is currently being developed to prevent HIV infections, benefiting from infrequent dosing and high efficacy. The crystal structure can affect the bioavailability and efficacy of cabotegravir. However, the stability determination of crystal structures of GSK744 have remained a challenge. Here, we introduced an ab initio protocol to determine the stability of the crystal structures of pharmaceutical molecules, which were obtained from crystal structure prediction process starting from the molecular diagram. Using GSK744 as a case study, the ab initio predicted that Gibbs free energy provides reliable further refinement of the predicted crystal structures and presents its capability for becoming a crystal stability determination approach in the future. The proposed work can assist in the comprehensive screening of pharmaceutical design and can provide structural predictions and stability evaluation for pharmaceutical crystals.


Asunto(s)
Dicetopiperazinas/química , Infecciones por VIH/tratamiento farmacológico , Inhibidores de Integrasa VIH/química , VIH-1/efectos de los fármacos , Piridonas/química , Fármacos Anti-VIH/química , Fármacos Anti-VIH/uso terapéutico , Cristalografía por Rayos X , Dicetopiperazinas/uso terapéutico , Infecciones por VIH/genética , Infecciones por VIH/virología , Inhibidores de Integrasa VIH/uso terapéutico , VIH-1/genética , VIH-1/ultraestructura , Humanos , Piridonas/uso terapéutico , Teoría Cuántica
12.
Neurobiol Dis ; 134: 104617, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31669733

RESUMEN

As the most common cause of progressive cognitive decline in humans, Alzheimer's disease (AD) has been intensively studied, but the mechanisms underlying its profound synaptic dysfunction remain unclear. Here we confirm that exposing wild-type mice to an enriched environment (EE) facilitates signaling in the hippocampus that promotes long-term potentiation (LTP). Exposing the hippocampus of mice kept in standard housing to soluble Aß oligomers impairs LTP, but EE can fully prevent this. Mechanistically, the key molecular features of the EE benefit are an upregulation of miRNA-132 and an inhibition of histone deacetylase (HDAC) signaling. Specifically, soluble Aß oligomers decreased miR-132 expression and increased HDAC3 levels in cultured primary neurons. Further, we provide evidence that HDAC3 is a direct target of miR-132. Overexpressing miR-132 or injecting an HDAC3 inhibitor into mice in standard housing mimics the benefits of EE in enhancing hippocampal LTP and preventing hippocampal impairment by Aß oligomers in vivo. We conclude that EE enhances hippocampal synaptic plasticity by upregulating miRNA-132 and reducing HDAC3 signaling in a way that counteracts the synaptotoxicity of human Aß oligomers. Our findings provide a rationale for prolonged exposure to cognitive novelty and/or epigenetic modulation to lessen the progressive effects of Aß accumulation during human brain aging.


Asunto(s)
Enfermedad de Alzheimer , Péptidos beta-Amiloides/toxicidad , Histona Desacetilasas/metabolismo , Vivienda para Animales , Potenciación a Largo Plazo/fisiología , MicroARNs/metabolismo , Animales , Femenino , Regulación de la Expresión Génica/fisiología , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Humanos , Masculino , Ratones , Transducción de Señal/fisiología
13.
Hum Mol Genet ; 26(1): 233-242, 2017 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-28011710

RESUMEN

Chromogranins are pro-hormone secretory proteins released from neuroendocrine cells, with effects on control of blood pressure. We conducted a genome-wide association study for plasma catestatin, the catecholamine release inhibitory peptide derived from chromogranin A (CHGA), and other CHGA- or chromogranin B (CHGB)-related peptides, in 545 US and 1252 Australian subjects. This identified loci on chromosomes 4q35 and 5q34 affecting catestatin concentration (P = 3.40 × 10-30 for rs4253311 and 1.85 × 10-19 for rs2731672, respectively). Genes in these regions include the proteolytic enzymes kallikrein (KLKB1) and Factor XII (F12). In chromaffin cells, CHGA and KLKB1 proteins co-localized in catecholamine storage granules. In vitro, kallikrein cleaved recombinant human CHGA to catestatin, verified by mass spectrometry. The peptide identified from this digestion (CHGA360-373) selectively inhibited nicotinic cholinergic stimulated catecholamine release from chromaffin cells. A proteolytic cascade involving kallikrein and Factor XII cleaves chromogranins to active compounds both in vivo and in vitro.


Asunto(s)
Biomarcadores/metabolismo , Catecolaminas/metabolismo , Células Cromafines/metabolismo , Cromogranina A/sangre , Sitios Genéticos/genética , Hipertensión/genética , Fragmentos de Péptidos/sangre , Adolescente , Glándulas Suprarrenales/metabolismo , Adulto , Anciano , Animales , Australia , Biomarcadores/análisis , Células Cultivadas , Factor XII/genética , Factor XII/metabolismo , Femenino , Estudio de Asociación del Genoma Completo , Humanos , Hipertensión/sangre , Calicreínas/genética , Calicreínas/metabolismo , Masculino , Ratones , Persona de Mediana Edad , Ratas , Estados Unidos , Adulto Joven
14.
Acta Neuropathol ; 136(4): 537-555, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29982852

RESUMEN

MicroRNAs (miRNA) regulate fundamental biological processes, including neuronal plasticity, stress response, and survival. Here, we describe a neuroprotective function of miR-132, the miRNA most significantly downregulated in neurons in Alzheimer's disease. We demonstrate that miR-132 protects primary mouse and human wild-type neurons and more vulnerable Tau-mutant neurons against amyloid ß-peptide (Aß) and glutamate excitotoxicity. It lowers the levels of total, phosphorylated, acetylated, and cleaved forms of Tau implicated in tauopathies, promotes neurite elongation and branching, and reduces neuronal death. Similarly, miR-132 attenuates PHF-Tau pathology and neurodegeneration, and enhances long-term potentiation in the P301S Tau transgenic mice. The neuroprotective effects are mediated by direct regulation of the Tau modifiers acetyltransferase EP300, kinase GSK3ß, RNA-binding protein Rbfox1, and proteases Calpain 2 and Caspases 3/7. These data suggest miR-132 as a master regulator of neuronal health and indicate that miR-132 supplementation could be of therapeutic benefit for the treatment of Tau-associated neurodegenerative disorders.


Asunto(s)
MicroARNs/genética , Transducción de Señal/genética , Tauopatías/genética , Péptidos beta-Amiloides/genética , Animales , Muerte Celular , Ácido Glutámico/toxicidad , Humanos , Ratones , Ratones Transgénicos , MicroARNs/fisiología , Mutación/genética , Degeneración Nerviosa/genética , Degeneración Nerviosa/patología , Neuritas/patología , Neuronas/patología , Cultivo Primario de Células , Procesamiento Proteico-Postraduccional , ARN Largo no Codificante/genética , Proteínas tau/genética
15.
J Cell Mol Med ; 21(4): 802-815, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-27885802

RESUMEN

p53-Transcriptional-regulated proteins interact with a large number of other signal transduction pathways in the cell, and a number of positive and negative autoregulatory feedback loops act upon the p53 response. P53 directly controls the POMC/α-MSH productions induced by ultraviolet (UV) and is associated with UV-independent pathological pigmentation. When identifying the causative gene of dyschromatosis universalis hereditaria (DUH), we found three mutations encoding amino acid substitutions in the gene SAM and SH3 domain containing 1 (SASH1), and SASH1 was associated with guanine nucleotide-binding protein subunit-alpha isoforms short (Gαs). However, the pathological gene and pathological mechanism of DUH remain unknown for about 90 years. We demonstrate that SASH1 is physiologically induced by p53 upon UV stimulation and SASH and p53 is reciprocally induced at physiological and pathophysiological conditions. SASH1 is regulated by a novel p53/POMC/α-MSH/Gαs/SASH1 cascade to mediate melanogenesis. A novel p53/POMC/Gαs/SASH1 autoregulatory positive feedback loop is regulated by SASH1 mutations to induce pathological hyperpigmentation phenotype. Our study demonstrates that a novel p53/POMC/Gαs/SASH1 autoregulatory positive feedback loop is regulated by SASH1 mutations to induce pathological hyperpigmentation phenotype.


Asunto(s)
Cromograninas/metabolismo , Retroalimentación Fisiológica , Subunidades alfa de la Proteína de Unión al GTP Gs/metabolismo , Hiperpigmentación/genética , Hiperpigmentación/patología , Mutación/genética , Proopiomelanocortina/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Proteínas Supresoras de Tumor/genética , Adolescente , Secuencia de Bases , Línea Celular , Humanos , Masculino , Melaninas/metabolismo , Melanosomas/metabolismo , Trastornos de la Pigmentación/congénito , Trastornos de la Pigmentación/genética , Trastornos de la Pigmentación/patología , Unión Proteica/efectos de la radiación , Transducción de Señal/efectos de la radiación , Enfermedades Cutáneas Genéticas/genética , Enfermedades Cutáneas Genéticas/patología , Rayos Ultravioleta , Regulación hacia Arriba/efectos de la radiación
16.
Cell Physiol Biochem ; 40(3-4): 509-526, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27889765

RESUMEN

BACKGROUND: Hirschsprung disease (HSCR) is a complex and heterogeneous disorder, characterized by a deficit in enteric nervous system. Genome-wide studies implied GABRG2, RELN and NRG3 might be involved in HSCR etiology. Here, we aimed to assess genetic variants in GABRG2, RELN and NRG3 that may confer susceptibility to HSCR and explore genetic interaction networks in HSCR. METHODS: Using a strategy that combined case-control study and gene-gene interaction analysis with the MassArray system, we evaluated 24 polymorphisms within GABRG2, RELN and NRG3 in 104 HSCR cases and 151 normal controls of Han Chinese origin. RESULTS: We observed that seven polymorphisms showed statistically significant differences between HSCR subjects and normal controls. For each of the three genes, the haplotypes which combined eight markers were the most significant. Moreover, we recruited SNPsyn, GO enrichment and MDR analyses to interrogate the interactions among GABRG2, RELN, NRG3 and our previous identified PTCH1 gene. Significant interaction networks were found among GABRG2, RELN, and PTCH1. CONCLUSION: We provide a first indication that common variants of GABRG2, RELN and NRG3 and the GABRG2-RELN-PTCH1 interaction networks might confer altered susceptibility to HSCR in the Han Chinese population, suggesting a potential mechanism underlying HSCR pathogenesis.


Asunto(s)
Moléculas de Adhesión Celular Neuronal/genética , Proteínas de la Matriz Extracelular/genética , Redes Reguladoras de Genes , Predisposición Genética a la Enfermedad , Enfermedad de Hirschsprung/genética , Proteínas del Tejido Nervioso/genética , Neurregulinas/genética , Polimorfismo de Nucleótido Simple/genética , Receptores de GABA-A/genética , Serina Endopeptidasas/genética , Alelos , Estudios de Casos y Controles , Femenino , Frecuencia de los Genes , Ontología de Genes , Estudios de Asociación Genética , Haplotipos/genética , Humanos , Lactante , Desequilibrio de Ligamiento/genética , Masculino , Espectrometría de Masas , Modelos Genéticos , Proteína Reelina , Factores de Riesgo
17.
Mol Ther ; 23(7): 1234-1247, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25903473

RESUMEN

Using in silico analysis of The Cancer Genome Atlas (TCGA), we identified microRNAs associated with glioblastoma (GBM) survival, and predicted their functions in glioma growth and progression. Inhibition of two "risky" miRNAs, miR-148a and miR-31, in orthotopic xenograft GBM mouse models suppressed tumor growth and thereby prolonged animal survival. Intracranial tumors treated with uncomplexed miR-148a and miR-31 antagomirs exhibited reduced proliferation, stem cell depletion, and normalized tumor vasculature. Growth-promoting functions of these two miRNAs were, in part, mediated by the common target, the factor inhibiting hypoxia-inducible factor 1 (FIH1), and the downstream pathways involving hypoxia-inducible factor HIF1α and Notch signaling. Therefore, miR-31 and miR-148a regulate glioma growth by maintaining tumor stem cells and their niche, and providing the tumor a way to activate angiogenesis even in a normoxic environment. This is the first study that demonstrates intratumoral uptake and growth-inhibiting effects of uncomplexed antagomirs in orthotopic glioma.


Asunto(s)
Neoplasias Encefálicas/genética , Glioblastoma/genética , MicroARNs/biosíntesis , Oligonucleótidos/administración & dosificación , Animales , Apoptosis/efectos de los fármacos , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/terapia , Proliferación Celular/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica , Genoma Humano , Glioblastoma/patología , Glioblastoma/terapia , Humanos , Ratones , MicroARNs/antagonistas & inhibidores , Neovascularización Patológica/genética , Neovascularización Patológica/patología , Transducción de Señal/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto
18.
Small Methods ; 8(1): e2300534, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37727096

RESUMEN

Deep learning has proven promising in biological and chemical applications, aiding in accurate predictions of properties such as atomic forces, energies, and material band gaps. Traditional methods with rotational invariance, one of the most crucial physical laws for predictions made by machine learning, have relied on Fourier transforms or specialized convolution filters, leading to complex model design and reduced accuracy and efficiency. However, models without rotational invariance exhibit poor generalization ability across datasets. Addressing this contradiction, this work proposes a rotationally invariant graph neural network, named RotNet, for accurate and accelerated quantum mechanical calculations that can overcome the generalization deficiency caused by rotations of molecules. RotNet ensures rotational invariance through an effective transformation and learns distance and angular information from atomic coordinates. Benchmark experiments on three datasets (protein fragments, electronic materials, and QM9) demonstrate that the proposed RotNet framework outperforms popular baselines and generalizes well to spatial data with varying rotations. The high accuracy, efficiency, and fast convergence of RotNet suggest that it has tremendous potential to significantly facilitate studies of protein dynamics simulation and materials engineering while maintaining physical plausibility.

19.
J Neurochem ; 127(6): 750-61, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23786442

RESUMEN

The Syrian Cardiomyopathic Hamster (BIO-14.6/53.58 strains) model of cardiac failure, resulting from naturally occurring deletion at the SGCD (delta-sarcoglycan) locus, displays widespread disturbances in catecholamine metabolism. Rare Mendelian myopathy disorders of human SGCD occur, although common naturally occurring SGCD genetic variation has not been evaluated for effects on human norepinephrine (NE) secretion. This study investigated the effect of SGCD genetic variation on control of NE secretion in healthy twin pairs. Genetic associations profiled SNPs across the SGCD locus. Trait heritability (h(2)) and genetic covariance (pleiotropy; shared h(2)) were evaluated. Sympathochromaffin exocytosis in vivo was probed in plasma by both catecholamines and Chromogranin B (CHGB). Plasma NE is substantially heritable (p = 3.19E-16, at 65.2 ± 5.0% of trait variance), sharing significant (p < 0.05) genetic determination with circulating and urinary catecholamines, CHGB, eGFR, and several cardio-metabolic traits. Participants with higher pNE showed significant (p < 0.05) differences in several traits, including increased BP and hypertension risk factors. Peak SGCD variant rs1835919 predicted elevated systemic vascular compliance, without changes in specifically myocardial traits. We used a chimeric-regulated secretory pathway photoprotein (CHGA-EAP) to evaluate the effect of SGCD on the exocytotic pathway in transfected PC12 cells; in transfected cells, expression of SGCD augmented CHGA trafficking into the exocytotic regulated secretory pathway. Thus, our investigation determined human NE secretion to be a highly heritable trait, influenced by common genetic variation within the SGCD locus. Circulating NE aggregates with BP and hypertension risk factors. In addition, coordinate NE and CHGB elevation by rs1835919 implicates exocytosis as the mechanism of release.


Asunto(s)
Sitios Genéticos , Patrón de Herencia , Polimorfismo de Nucleótido Simple , Sarcoglicanos/genética , Sistema Nervioso Simpático/fisiología , Adolescente , Adulto , Anciano , Animales , Cromogranina A/metabolismo , Exocitosis , Pleiotropía Genética , Humanos , Persona de Mediana Edad , Norepinefrina/sangre , Norepinefrina/metabolismo , Células PC12 , Transporte de Proteínas , Sitios de Carácter Cuantitativo , Carácter Cuantitativo Heredable , Ratas , Sarcoglicanos/metabolismo , Adulto Joven
20.
Mol Vis ; 19: 789-95, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23592915

RESUMEN

PURPOSE: To identify the genetic defect associated with autosomal dominant congenital cataract (ADCC) in a Chinese family, in which 11 individuals across four generations are affected with coralliform cataract. METHODS: Exome sequencing was performed in two of the ADCC-affected family members to scan for potential genetic defects. Sanger sequencing was used to verify these defects in the whole family. RESULTS: By combining whole exome sequencing and Sanger sequencing, the genetic defect was revealed to be a insertion of a cytosine after coding nucleotide 1,361 (1361insC) in the gap junction alpha 3 (GJA3) gene, causing a frameshift at codon 397 (p.Ala397Glyfs×71). This frameshift mutation cosegregates with the ADCC-affected pedigree members, but is absent in unaffected relatives and 100 normal individuals. CONCLUSIONS: A 1361 insC mutation in the C-terminus of GJA3 is found to be associated with autosomal dominant congenital coralliform cataract. This finding is similar to that of a previous publication, thus providing further evidence that the GJA3 C-terminal domain is also its mutation area, and further expanding the mutation spectrum of GJA3 in association with congenital cataract.


Asunto(s)
Pueblo Asiatico/genética , Catarata/congénito , Catarata/genética , Conexinas/genética , Estudios de Asociación Genética , Mutagénesis Insercional/genética , Mutación/genética , Secuencia de Aminoácidos , Secuencia de Bases , China , Biología Computacional , Conexinas/química , Análisis Mutacional de ADN , Técnicas de Diagnóstico Oftalmológico , Familia , Femenino , Genes Dominantes/genética , Predisposición Genética a la Enfermedad , Humanos , Masculino , Datos de Secuencia Molecular , Linaje , Estructura Secundaria de Proteína , Alineación de Secuencia
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