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1.
Mol Cell ; 81(8): 1781-1788.e4, 2021 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-33571424

RESUMEN

Mediator is a universal adaptor for transcription control. It serves as an interface between gene-specific activator or repressor proteins and the general RNA polymerase II (pol II) transcription machinery. Previous structural studies revealed a relatively small part of Mediator and none of the gene activator-binding regions. We have determined the cryo-EM structure of the Mediator at near-atomic resolution. The structure reveals almost all amino acid residues in ordered regions, including the major targets of activator proteins, the Tail module, and the Med1 subunit of the Middle module. Comparison of Mediator structures with and without pol II reveals conformational changes that propagate across the entire Mediator, from Head to Tail, coupling activator- and pol II-interacting regions.


Asunto(s)
Subunidad 1 del Complejo Mediador/metabolismo , Aminoácidos/genética , Conformación Proteica , ARN Polimerasa II/metabolismo , Factores de Transcripción/metabolismo , Transcripción Genética/genética
2.
Mol Cell ; 81(15): 3187-3204.e7, 2021 08 05.
Artículo en Inglés | MEDLINE | ID: mdl-34157307

RESUMEN

OTULIN coordinates with LUBAC to edit linear polyubiquitin chains in embryonic development, autoimmunity, and inflammatory diseases. However, the mechanism by which angiogenesis, especially that of endothelial cells (ECs), is regulated by linear ubiquitination remains unclear. Here, we reveal that constitutive or EC-specific deletion of Otulin resulted in arteriovenous malformations and embryonic lethality. LUBAC conjugates linear ubiquitin chains onto Activin receptor-like kinase 1 (ALK1), which is responsible for angiogenesis defects, inhibiting ALK1 enzyme activity and Smad1/5 activation. Conversely, OTULIN deubiquitinates ALK1 to promote Smad1/5 activation. Consistently, embryonic survival of Otulin-deficient mice was prolonged by BMP9 pretreatment or EC-specific ALK1Q200D (constitutively active) knockin. Moreover, mutant ALK1 from type 2 hereditary hemorrhagic telangiectasia (HHT2) patients exhibited excessive linear ubiquitination and increased HOIP binding. As such, a HOIP inhibitor restricted the excessive angiogenesis of ECs derived from ALK1G309S-expressing HHT2 patients. These results show that OTULIN and LUBAC govern ALK1 activity to balance EC angiogenesis.


Asunto(s)
Receptores de Activinas Tipo II/genética , Receptores de Activinas Tipo II/metabolismo , Endopeptidasas/genética , Complejos Multiproteicos/metabolismo , Neovascularización Patológica/genética , Poliubiquitina/metabolismo , Adulto , Animales , Endopeptidasas/metabolismo , Células Endoteliales/efectos de los fármacos , Células Endoteliales/metabolismo , Femenino , Factor 2 de Diferenciación de Crecimiento/farmacología , Células Endoteliales de la Vena Umbilical Humana , Humanos , Masculino , Ratones Mutantes , Mutación , Neovascularización Patológica/tratamiento farmacológico , Neovascularización Patológica/metabolismo , Neovascularización Fisiológica/genética , Proteína Smad1/genética , Proteína Smad1/metabolismo , Proteína Smad5/genética , Proteína Smad5/metabolismo , Telangiectasia Hemorrágica Hereditaria , Ubiquitina-Proteína Ligasas/metabolismo
3.
Genes Dev ; 32(1): 58-69, 2018 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-29437725

RESUMEN

Histone acetylation is associated with active transcription in eukaryotic cells. It helps to open up the chromatin by neutralizing the positive charge of histone lysine residues and providing binding platforms for "reader" proteins. The bromodomain (BRD) has long been thought to be the sole protein module that recognizes acetylated histones. Recently, we identified the YEATS domain of AF9 (ALL1 fused gene from chromosome 9) as a novel acetyl-lysine-binding module and showed that the ENL (eleven-nineteen leukemia) YEATS domain is an essential acetyl-histone reader in acute myeloid leukemias. The human genome encodes four YEATS domain proteins, including GAS41, a component of chromatin remodelers responsible for H2A.Z deposition onto chromatin; however, the importance of the GAS41 YEATS domain in human cancer remains largely unknown. Here we report that GAS41 is frequently amplified in human non-small cell lung cancer (NSCLC) and is required for cancer cell proliferation, survival, and transformation. Biochemical and crystal structural studies demonstrate that GAS41 binds to histone H3 acetylated on H3K27 and H3K14, a specificity that is distinct from that of AF9 or ENL. ChIP-seq (chromatin immunoprecipitation [ChIP] followed by high-throughput sequencing) analyses in lung cancer cells reveal that GAS41 colocalizes with H3K27ac and H3K14ac on the promoters of actively transcribed genes. Depletion of GAS41 or disruption of the interaction between its YEATS domain and acetylated histones impairs the association of histone variant H2A.Z with chromatin and consequently suppresses cancer cell growth and survival both in vitro and in vivo. Overall, our study identifies GAS41 as a histone acetylation reader that promotes histone H2A.Z deposition in NSCLC.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Histonas/metabolismo , Neoplasias Pulmonares/metabolismo , Factores de Transcripción/metabolismo , Acetilación , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Línea Celular Tumoral , Proliferación Celular , Amplificación de Genes , Genes cdc , Histonas/fisiología , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Regiones Promotoras Genéticas , Dominios y Motivos de Interacción de Proteínas , Factores de Transcripción/química , Factores de Transcripción/genética , Factores de Transcripción/fisiología
4.
RNA ; 29(7): 1007-1019, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37001915

RESUMEN

The multifunctional RNA recognition motif-containing protein Y14/RBM8A participates in mRNA metabolism and is essential for the efficient repair of DNA double-strand breaks (DSBs). Y14 contains highly charged, low-complexity sequences in both the amino- and carboxy-terminal domains. The feature of charge segregation suggests that Y14 may undergo liquid-liquid phase separation (LLPS). Recombinant Y14 formed phase-separated droplets, which were sensitive to pH and salt concentration. Domain mapping suggested that LLPS of Y14 involves multivalent electrostatic interactions and is partly determined by the net charge of its low-complexity regions. Phospho-mimicry of the carboxy-terminal arginine-serine dipeptides of Y14 suppressed phase separation. Moreover, RNA could phase separate into Y14 droplets and modulate Y14 LLPS in a concentration-dependent manner. Finally, the capacity of Y14 in LLPS and coacervation with RNA in vitro correlated with its activity in DSB repair. These results reveal a molecular rule for LLPS of Y14 in vitro and an implication for its co-condensation with RNA in genome stability.


Asunto(s)
Arginina , ARN , ARN/genética , Arginina/química , Dominios Proteicos , Proteínas de Unión al ARN/metabolismo , Reparación del ADN
5.
Plant Physiol ; 194(4): 2101-2116, 2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-37995372

RESUMEN

The precise timing of flowering plays a pivotal role in ensuring successful plant reproduction and seed production. This process is intricately governed by complex genetic networks that integrate internal and external signals. This study delved into the regulatory function of microRNA397 (miR397) and its target gene LACCASE-15 (OsLAC15) in modulating flowering traits in rice (Oryza sativa). Overexpression of miR397 led to earlier heading dates, decreased number of leaves on the main stem, and accelerated differentiation of the spikelet meristem. Conversely, overexpression of OsLAC15 resulted in delayed flowering and prolonged vegetative growth. Through biochemical and physiological assays, we uncovered that miR397-OsLAC15 had a profound impact on carbohydrate accumulation and photosynthetic assimilation, consequently enhancing the photosynthetic intensity in miR397-overexpressing rice plants. Notably, we identified that OsLAC15 is at least partially localized within the peroxisome organelle, where it regulates the photorespiration pathway. Moreover, we observed that a high CO2 concentration could rescue the late flowering phenotype in OsLAC15-overexpressing plants. These findings shed valuable insights into the regulatory mechanisms of miR397-OsLAC15 in rice flowering and provided potential strategies for developing crop varieties with early flowering and high-yield traits through genetic breeding.


Asunto(s)
Oryza , Oryza/metabolismo , Flores/fisiología , Fitomejoramiento , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , Reproducción , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulación de la Expresión Génica de las Plantas
6.
Mol Psychiatry ; 29(5): 1550-1566, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38361128

RESUMEN

Major depressive disorder (MDD) is characterized by diverse debilitating symptoms that include loss of motivation and anhedonia. If multiple medications, psychotherapy, and electroconvulsive therapy fail in some patients with MDD, their condition is then termed treatment-resistant depression (TRD). MDD can be associated with abnormalities in the reward-system-dopaminergic mesolimbic pathway, in which the nucleus accumbens (NAc) and ventral tegmental area (VTA) play major roles. Deep brain stimulation (DBS) applied to the NAc alleviates the depressive symptoms of MDD. However, the mechanism underlying the effects of this DBS has remained elusive. In this study, using the chronic unpredictable mild stress (CUMS) mouse model, we investigated the behavioral and neurobiological effects of NAc-DBS on the multidimensional depression-like phenotypes induced by CUMS by integrating behavioral, in vivo microdialysis coupled with high-performance liquid chromatography-electrochemical detector (HPLC-ECD), calcium imaging, pharmacological, and genetic manipulation methods in freely moving mice. We found that long-term and repeated, but not single, NAc-DBS induced robust antidepressant responses in CUMS mice. Moreover, even a single trial NAc-DBS led to the elevation of the γ-aminobutyric acid (GABA) neurotransmitter, accompanied by the increase in dopamine (DA) neuron activity in the VTA. Both the inhibition of the GABAA receptor activity and knockdown of the GABAA-α1 gene in VTA-GABA neurons blocked the antidepressant effect of NAc-DBS in CUMS mice. Our results showed that NAc-DBS could disinhibit VTA-DA neurons by regulating the level of GABA and the activity of VTA-GABA in the VTA and could finally correct the depression-like behaviors in the CUMS mouse model.


Asunto(s)
Estimulación Encefálica Profunda , Depresión , Trastorno Depresivo Mayor , Modelos Animales de Enfermedad , Neuronas Dopaminérgicas , Núcleo Accumbens , Estrés Psicológico , Área Tegmental Ventral , Animales , Área Tegmental Ventral/metabolismo , Núcleo Accumbens/metabolismo , Neuronas Dopaminérgicas/metabolismo , Ratones , Masculino , Estimulación Encefálica Profunda/métodos , Depresión/terapia , Depresión/metabolismo , Trastorno Depresivo Mayor/terapia , Trastorno Depresivo Mayor/metabolismo , Estrés Psicológico/terapia , Estrés Psicológico/metabolismo , Ratones Endogámicos C57BL , Dopamina/metabolismo , Conducta Animal/fisiología , Ácido gamma-Aminobutírico/metabolismo
7.
Nucleic Acids Res ; 51(18): 10049-10058, 2023 10 13.
Artículo en Inglés | MEDLINE | ID: mdl-37665001

RESUMEN

PmrA, an OmpR/PhoB-family response regulator, triggers gene transcription responsible for polymyxin resistance in bacteria by recognizing promoters where the canonical-35 element is replaced by the pmra-box, representing the PmrA recognition sequence. Here, we report a cryo-electron microscopy (cryo-EM) structure of a bacterial PmrA-dependent transcription activation complex (TAC) containing a PmrA dimer, an RNA polymerase σ70 holoenzyme (RNAPH) and the pbgP promoter DNA. Our structure reveals that the RNAPH mainly contacts the PmrA C-terminal DNA-binding domain (DBD) via electrostatic interactions and reorients the DBD three base pairs upstream of the pmra-box, resulting in a dynamic TAC conformation. In vivo assays show that the substitution of the DNA-recognition residue eliminated its transcriptional activity, while variants with altered RNAPH-interacting residues resulted in enhanced transcriptional activity. Our findings suggest that both PmrA recognition-induced DNA distortion and PmrA promoter escape play crucial roles in its transcriptional activation.


Asunto(s)
Proteínas Bacterianas , Activación Transcripcional , Proteínas Bacterianas/metabolismo , Microscopía por Crioelectrón , ADN/genética , ADN/química , ARN Polimerasas Dirigidas por ADN/metabolismo , Escherichia coli , Regulación Bacteriana de la Expresión Génica , Klebsiella pneumoniae/metabolismo , Transcripción Genética
8.
Genomics ; 116(5): 110886, 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38880312

RESUMEN

BACKGROUND: Fibre diameter is an important economic trait of wool fibre. As the fibre diameter decreases, the economic value of wool increases. Therefore, understanding the mechanism of wool fibre diameter regulation is important in improving the value of wool. RESULTS: In this study, we used non-targeted metabolome and reference transcriptome data to detect differences in metabolites and genes in groups of Alpine Merino sheep with different wool fibre diameter gradients, and integrated metabolome and transcriptome data to identify key genes and metabolites that regulate wool fibre diameter. We found 464 differentially abundant metabolites (DAMs) and 901 differentially expressed genes (DEGs) in four comparisons of groups with different wool fibre diameters. Approximately 25% of the differentially abundant metabolites were lipid and lipid-like molecules. These molecules were predicted to be associated with skin development and keratin filament by gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) functional enrichment analyses. Key genes, including COL5A2, COL5A3, CREB3L4, COL1A1, and SFRP4, were identified by gene set enrichment analysis. CONCLUSIONS: Key genes regulating wool fibre diameter were identified, the effects of lipid molecules on wool performance were investigated, and potential synergies between genes and metabolites were postulated, providing a theoretical framework for fine wool sheep breeding.

9.
J Biol Chem ; 299(11): 105315, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37797700

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 , Proteómica
10.
BMC Genomics ; 25(1): 606, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38886664

RESUMEN

BACKGROUND: Gangba sheep as a famous breed of Tibetan sheep, its wool color is mainly white and black. Gangba wool is economically important as a high-quality raw material for Tibetan blankets and Tibetan serge. However, relatively few studies have been conducted on the wool color of Tibetan sheep. RESULTS: To fill this research gap, this study conducted an in-depth analysis of two populations of Gangba sheep (black and white wool color) using whole genome resequencing to identify genetic variation associated with wool color. Utilizing PCA, Genetic Admixture, and N-J Tree analyses, the present study revealed a consistent genetic relationship and structure between black and white wool colored Gangba sheep populations, which is consistent with their breed history. Analysis of selection signatures using multiple methods (FST, π ratio, Tajima's D), 370 candidate genes were screened in the black wool group (GBB vs GBW); among them, MC1R, MLPH, SPIRE2, RAB17, SMARCA4, IRF4, CAV1, USP7, TP53, MYO6, MITF, MC2R, TET2, NF1, JAK1, GABRR1 genes are mainly associated with melanin synthesis, melanin delivery, and distribution. The enrichment results of the candidate genes identified 35 GO entries and 19 KEGG pathways associated with the formation of the black phenotype. 311 candidate genes were screened in the white wool group (GBW vs GBB); among them, REST, POU2F1, ADCY10, CCNB1, EP300, BRD4, GLI3, and SDHA genes were mainly associated with interfering with the differentiation of neural crest cells into melanocytes, affecting the proliferation of melanocytes, and inhibiting melanin synthesis. 31 GO entries and 22 KEGG pathways were associated with the formation of the white phenotype. CONCLUSIONS: This study provides important information for understanding the genetic mechanism of wool color in Gangba, and provides genetic knowledge for improving and optimizing the wool color of Tibetan sheep. Genetic improvement and selective breeding to produce wool of specific colors can meet the demand for a diversity of wool products in the Tibetan wool textile market.


Asunto(s)
Polimorfismo de Nucleótido Simple , Lana , Animales , Ovinos/genética , Selección Genética , Pigmentación/genética , Estudio de Asociación del Genoma Completo
11.
BMC Genomics ; 25(1): 641, 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38937677

RESUMEN

BACKGROUND: The Alpine Merino is a new breed of fine-wool sheep adapted to the cold and arid climate of the plateau in the world. It has been popularized in Northwest China due to its superior adaptability as well as excellent production performance. Those traits related to body weight, wool yield, and wool fiber characteristics, which are economically essential traits in Alpine Merino sheep, are controlled by QTL (Quantitative Trait Loci). Therefore, the identification of QTL and genetic markers for these key economic traits is a critical step in establishing a MAS (Marker-Assisted Selection) breeding program. RESULTS: In this study, we constructed the high-density genetic linkage map of Alpine Merino sheep by sequencing 110 F1 generation individuals using WGR (Whole Genome Resequencing) technology. 14,942 SNPs (Single Nucleotide Polymorphism) were identified and genotyped. The map spanned 2,697.86 cM, with an average genetic marker interval of 1.44 cM. A total of 1,871 high-quality SNP markers were distributed across 27 linkage groups, with an average of 69 markers per LG (Linkage Group). Among them, the smallest genetic distance is 19.62 cM for LG2, while the largest is 237.19 cM for LG19. The average genetic distance between markers in LGs ranged from 0.24 cM (LG2) to 3.57 cM (LG17). The marker density in the LGs ranged from LG14 (39 markers) to LG1 (150 markers). CONCLUSIONS: The first genetic map of Alpine Merino sheep we constructed included 14,942 SNPs, while 46 QTLs associated with body weight, wool yield and wool fiber traits were identified, laying the foundation for genetic studies and molecular marker-assisted breeding. Notably, there were QTL intervals for overlapping traits on LG4 and LG8, providing potential opportunities for multi-trait co-breeding and further theoretical support for selection and breeding of ultra-fine and meaty Alpine Merino sheep.


Asunto(s)
Peso Corporal , Mapeo Cromosómico , Polimorfismo de Nucleótido Simple , Sitios de Carácter Cuantitativo , Lana , Animales , Peso Corporal/genética , Lana/crecimiento & desarrollo , Ovinos/genética , Ligamiento Genético , Marcadores Genéticos , Secuenciación Completa del Genoma , Fenotipo , Oveja Doméstica/genética , Genotipo
12.
Eur J Immunol ; 53(9): e2250211, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37377275

RESUMEN

Type I interferons (IFN-Is) are a class of proinflammatory cytokines produced in response to viruses and environmental stimulations, resulting in chronic inflammation and even carcinogenesis. However, the connection between IFN-I and p53 mutation is poorly understood. Here, we investigated IFN-I status in the context of mutant p53 (p53N236S , p53S). We observed significant cytosolic double-stranded DNA (dsDNA) derived from nuclear heterochromatin in p53S cells, along with an increased expression of IFN-stimulated genes. Further study revealed that p53S promoted cyclic GMP-AMP synthase (cGAS) and IFN-regulatory factor 9 (IRF9) expression, thus activating the IFN-I pathway. However, p53S/S mice were more susceptible to herpes simplex virus 1 infection, and the cGAS-stimulator of IFN genes (STING) pathway showed a decline trend in p53S cells in response to poly(dA:dT) accompanied with decreased IFN-ß and IFN-stimulated genes, whereas the IRF9 increased in response to IFN-ß stimulation. Our results illustrated the p53S mutation leads to low-grade IFN-I-induced inflammation via consistent low activation of the cGAS-STING-IFN-I axis, and STAT1-IRF9 pathway, therefore, impairs the protective cGAS-STING signalling and IFN-I response encountered with exogenous DNA attack. These results suggested the dual molecular mechanisms of p53S mutation in inflammation regulation. Our results could be helping in further understanding of mutant p53 function in chronic inflammation and provide information for developing new therapeutic strategies for chronic inflammatory diseases or cancer.


Asunto(s)
Interferón Tipo I , Proteína p53 Supresora de Tumor , Ratones , Animales , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Nucleotidiltransferasas/genética , Interferón Tipo I/metabolismo , Transducción de Señal/genética , Inflamación , Inmunidad Innata/genética
13.
Small ; 20(21): e2309961, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38098343

RESUMEN

Different phases of Ga2O3 have been regarded as superior platforms for making new-generation high-performance electronic devices. However, understanding of thermal transport in different phases of nanoscale Ga2O3 thin-films remains challenging, owing to the lack of phonon transport models and systematic experimental investigations. Here, thermal conductivity (TC) and thermal boundary conductance (TBC) of the ( 1 ¯ 010 ) $( {\bar 1010} )$ α-, ( 2 ¯ 01 ) $( {\bar 201} )\;$ ß-, and (001) κ-Ga2O3 thin films on sapphire are investigated. At ≈80 nm, the measured TC of α (8.8 W m-1 K-1) is ≈1.8 times and ≈3.0 times larger than that of ß and κ, respectively, consistent with model based on density functional theory (DFT), whereas the model reveals a similar TC for the bulk α- and ß-Ga2O3. The observed phase- and size-dependence of TC is discussed thoroughly with phonon transport properties such as phonon mean free path and group velocity. The measured TBC at Ga2O3/sapphire interface is analyzed with diffuse mismatch model using DFT-derived full phonon dispersion relation. Phonon spectral distribution of density of states, transmission coefficients, and group velocity are studied to understand the phase-dependence of TBC. This study provides insight into the fundamental phonon transport mechanism in Ga2O3 thin films and paves the way for improved thermal management of high-power Ga2O3-based devices.

14.
Small ; 20(9): e2305798, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37849041

RESUMEN

As the most popular liquid metal (LM), gallium (Ga) and its alloys are emerging as functional materials due to their unique combination of fluidic and metallic properties near room temperature. As an important branch of utilizing LMs, micro- and submicron-particles of Ga-based LM are widely employed in wearable electronics, catalysis, energy, and biomedicine. Meanwhile, the phase transition is crucial not only for the applications based on this reversible transformation process, but also for the solidification temperature at which fluid properties are lost. While Ga has several solid phases and exhibits unusual size-dependent phase behavior. This complex process makes the phase transition and undercooling of Ga uncontrollable, which considerably affects the application performance. In this work, extensive (nano-)calorimetry experiments are performed to investigate the polymorph selection mechanism during liquid Ga crystallization. It is surprisingly found that the crystallization temperature and crystallization pathway to either α -Ga or ß -Ga can be effectively engineered by thermal treatment and droplet size. The polymorph selection process is suggested to be highly relevant to the capability of forming covalent bonds in the equilibrium supercooled liquid. The observation of two different crystallization pathways depending on the annealing temperature may indicate that there exist two different liquid phases in Ga.

15.
Clin Genet ; 105(1): 52-61, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37822034

RESUMEN

Haplotype-based noninvasive prenatal diagnosis (NIPD) is applicable for various recessive single-gene disorders in proband families. However, a comprehensive exploration of critical factors influencing the assay performance, such as fetal fraction, informative single nucleotide polymorphism (SNP) count, and recombination events, has yet to be performed. It is critical to identify key factors affecting NIPD performance, including its accuracy and success rate, and their impact on clinical diagnostics to guide clinical practice. We conducted a prospective study, recruiting 219 proband families with singleton pregnancies at risk for eight recessive single-gene disorders (Duchenne muscular dystrophy, spinal muscular atrophy, phenylketonuria, methylmalonic acidemia, hemophilia A, hemophilia B, non-syndromic hearing loss, and congenital adrenal hyperplasia) at 7-14 weeks of gestation. Haplotype-based NIPD was performed by evaluating the relative haplotype dosage (RHDO) in maternal circulation, and the results were validated via invasive prenatal diagnosis or newborn follow-ups. Among the 219 families, the median gestational age at first blood draw was 8+5 weeks. Initial testing succeeded for 190 families and failed for 29 due to low fetal fraction (16), insufficient informative SNPs (9), and homologous recombination near pathogenic variation (4). Among low fetal fraction families, successful testing was achieved for 11 cases after a redraw, while 5 remained inconclusive. Test failures linked to insufficient informative SNPs correlated with linkage disequilibrium near the genes, with F8 and MMUT exhibiting the highest associated failure rates (14.3% and 25%, respectively). Homologous recombination was relatively frequent around the DMD and SMN1 genes (8.8% and 4.8%, respectively) but led to detection failure in only 44.4% (4/9) of such cases. All NIPD results from the 201 successful families were consistent with invasive diagnostic findings or newborn follow-up. Fetal fraction, informative SNPs count, and homologous recombination are pivotal to NIPD performance. Redrawing blood effectively improves the success rate for low fetal fraction samples. However, informative SNPs count and homologous recombination rates vary significantly across genes, necessitating careful consideration in clinical practice. We have designed an in silico method based on linkage disequilibrium data to predict the number of informative SNPs. This can identify genomic regions where there might be an insufficient number of SNPs, thereby guiding panel design. With these factors properly accounted for, NIPD is highly accurate and reliable.


Asunto(s)
Distrofia Muscular de Duchenne , Pruebas Prenatales no Invasivas , Embarazo , Femenino , Recién Nacido , Humanos , Lactante , Pruebas Prenatales no Invasivas/métodos , Haplotipos/genética , Estudios Prospectivos , Diagnóstico Prenatal/métodos , Distrofia Muscular de Duchenne/diagnóstico
16.
Anticancer Drugs ; 35(1): 46-54, 2024 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-37449977

RESUMEN

Protein degraders are currently under rapid development as a promising modality for drug discovery. They are compounds that orchestrate interactions between a target protein and an E3 ubiquitin ligase, prompting intracellular protein degradation through proteasomal pathway. More protein degraders identification will greatly promote the development of this field. BAG3 is widely recognized as an excellent therapeutic target in cancer treatments. Exploring protein degraders that target BAG3 degradation has profound implications. Herein, molecular docking was applied to assess binding energy between 81 clinical phase I kinase inhibitors and BAG3. BAG3 protein and mRNA level were detected by western blot and quantitative real-time PCR. CCK8 assay and colony formation assay were applied to detect the cell viability and proliferation rate. Cell death was accessed using flow cytometry combined with PI and Annexin V double staining. AZD7762, a Chk1 kinase inhibitor, was identified to induce BAG3 degradation in a ubiquitin-proteasome pathway. AZD7762-induced BAG3 degradation was not dependent on Chk1 expression or activity. CRBN, an E3 ligase, was identified to bind to BAG3 and mediated BAG3 ubiquitination in the presence of AZD7762. By targeting Chk1 and BAG3, two ideal therapeutic targets in cancer treatment, AZD7762 would be a powerful chemotherapy agent in the future.


Asunto(s)
Complejo de la Endopetidasa Proteasomal , Ubiquitina-Proteína Ligasas , Humanos , Complejo de la Endopetidasa Proteasomal/metabolismo , Línea Celular Tumoral , Simulación del Acoplamiento Molecular , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitinas/metabolismo , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas Reguladoras de la Apoptosis/metabolismo
17.
Bioorg Med Chem Lett ; 109: 129822, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38823728

RESUMEN

The quest for novel antibacterial agents is imperative in the face of escalating antibiotic resistance. Naturally occurring tetrahydro-ß-carboline (THßC) alkaloids have been highlighted due to their significant biological derivatives. However, these structures have been little explored for antibacterial drugs development. In this study, a series of 1,2,3,4-THßC derivatives were synthesized and assessed for their antibacterial prowess against both gram-positive and gram-negative bacteria. The compounds exhibited moderate to good antibacterial activity, with some compounds showing superior efficacy against gram-positive bacteria, especially methicillin-resistant Staphylococcus aureus (MRSA), to that of Gentamicin. Among these analogs, compound 3k emerged as a hit compound, demonstrating rapid bactericidal action and a significant post-antibacterial effect, with significant cytotoxicity towards human LO2 and HepG2 cells. In addition, compound 3k (10 mg/kg) showed comparable anti-MRSA efficacy to Ciprofloxacin (2 mg/kg) in a mouse model of abdominal infection. Overall, the present findings suggested that THßC derivatives based on the title compounds hold promising applications in the development of antibacterial drugs.


Asunto(s)
Antibacterianos , Carbolinas , Bacterias Gramnegativas , Bacterias Grampositivas , Pruebas de Sensibilidad Microbiana , Antibacterianos/farmacología , Antibacterianos/síntesis química , Antibacterianos/química , Carbolinas/farmacología , Carbolinas/química , Carbolinas/síntesis química , Humanos , Relación Estructura-Actividad , Animales , Ratones , Bacterias Grampositivas/efectos de los fármacos , Estructura Molecular , Bacterias Gramnegativas/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Células Hep G2 , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos
18.
Environ Res ; 242: 117781, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38036212

RESUMEN

In this study, a novel magnetic nanocomposite of Ru@Fe3O4/rGO was successfully synthesized by a simple hydro-thermal method. The Ru@Fe3O4/rGO particles were assembled and immobilized for innovative magnetically assembled electrode (MAE) without any binder, and the electrode was further applied in heterogeneous electro-Fenton (hetero-EF) process for the degradation of diclofenac (DCF). The results showed that rGO could remarkably enhance the conductivity and catalyze the two-electron oxygen reduction, which greatly improved the generation of H2O2. In addition, the mixture valence of Fe and Ru species might provide rich reaction sites and enhance electron transfer by synergy. Thus, the Ru@Fe3O4/rGO MAE exhibited a stable and high electrocatalytic activity in the hetero-EF process for DCF degradation over a wide pH range from 2 to 9 owing to the higher electroactive surface area (EASA) and lower charge/mass-transfer resistance. The DCF degradation efficiency could reach about 100% within 90 min under pH 5 and current 40 mA, and the Ru@Fe3O4/rGO MAE showed high stability and reusability after five cycles. Theoretically, 1O2 and •OH were the main reactive oxygen species (ROS) participating in DCF degradation in the Ru@Fe3O4/rGO MAE hetero-EF process. Furthermore, according to the LC-MS/MS intermediates, the possible DCF degradation pathway was deduced including dechlorination, hydroxylation and ring opening attacked by ROS. Eleven intermediates were detected during DCF degradation in the MAE hetero-EF process, and the ecological risk of DCF degradation in Ru@Fe3O4/rGO MAE hetero-EF process was significantly reduced. This study provides new insights into the magnetically assembled electrode of Ru@Fe3O4/rGO and displays a new practical application prospect of the materials for high-efficient removal and degradation of DCF from wastewater.


Asunto(s)
Diclofenaco , Contaminantes Químicos del Agua , Peróxido de Hidrógeno , Especies Reactivas de Oxígeno , Cromatografía Liquida , Espectrometría de Masas en Tándem , Electrodos , Oxidación-Reducción
19.
Dermatology ; 240(2): 233-242, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37939682

RESUMEN

BACKGROUND: Detergent is a chemical product commonly used in people's daily life. Contact with detergent solutions can damage the human skin barrier and cause skin diseases. Skin surface lipids (SSLs) play a decisive role in skin barrier function. This study aimed to observe the changes of SSLs in young adults after exposure to detergent solutions to explore the underlying mechanism of skin barrier function damage. METHODS: A self-controlled study on youth adults was conducted in Zhengzhou, China, in November 2020. The study lasted for a total of 1 week, and skin barrier function was assessed by trans-epidermal water loss (TEWL) values. The changes of SSLs before and after exposure to the detergent with subjects were measured using ultra-performance liquid chromatography quadrupole time of flight mass spectrometry. RESULTS: The skin barrier function of subjects' hands was impaired after exposure to detergent (TEWL value increased, p < 0.001). A total of 520 SSLs were detected, divided into 6 main categories. The average relative abundance of these 6 major lipids decreased after exposure. Sphingolipids (mainly ceramides), free fatty acids (mainly long-chain fatty acids), cholesterol lipids, and glycerophospholipids are the most severely damaged lipids. CONCLUSION: Detergent solutions can damage the skin barrier function and SSLs of young hands; interventions targeting SSLs to eliminate detergent damage to human skin may be of value.


Asunto(s)
Detergentes , Lipidómica , Humanos , Adulto Joven , Adolescente , Detergentes/efectos adversos , Detergentes/análisis , Piel , Epidermis/química , Agua , Lípidos/análisis , Lípidos/química , Lípidos/farmacología
20.
J Eur Acad Dermatol Venereol ; 38 Suppl 6: 26-36, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38419560

RESUMEN

BACKGROUND: Noninvasive energy-based device (NI-EBD) aesthetic procedures has recently gained widespread usage for treating various skin conditions, enhancing skin texture and performing rejuvenation-related procedures. However, practically all NI-EBD procedures result in variable degrees of damage to the skin barrier, inducing pathological and physiological processes such as oxidative stress and inflammation, and only a small percentage of individuals possess the innate ability to restore it. OBJECTIVE: To introduce the concept of integrated skincare and establish standardized operational procedures for perioperative integrated skincare, and furnish a theoretical basis for clinical diagnosis and treatment performed by professional medical aestheticians. METHODS: The author leveraged domestic and international guidelines, clinical practice expertise and evidence-based research, adapting them to suit the specific circumstances in China. RESULTS: The consensus were provided four parts, including concept and essence of integrated skincare, integrated skincare significance during the perioperative phase of NI-EBD procedures, active ingredients and functions of effective skincare products, standardized perioperative skincare procedure for NI-EBD procedures and precautions. For the standardized perioperative skincare procedure, four recommendations were listed according to different stages during NI-EBD procedures. CONCLUSION: These recommendations create the 'Expert Consensus on Perioperative Integrated Skincare for Noninvasive Energy-Based Device Aesthetic Procedures in Clinical Practice in China'.


Asunto(s)
Técnicas Cosméticas , Humanos , China , Atención Perioperativa , Consenso , Rejuvenecimiento , Cuidados de la Piel/métodos , Envejecimiento de la Piel , Estética
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