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The biophysical properties of the cytoplasm are major determinants of key cellular processes and adaptation. Many yeasts produce dormant spores that can withstand extreme conditions. We show that spores of Saccharomyces cerevisiae exhibit extraordinary biophysical properties, including a highly viscous and acidic cytosol. These conditions alter the solubility of more than 100 proteins such as metabolic enzymes that become more soluble as spores transit to active cell proliferation upon nutrient repletion. A key regulator of this transition is the heat shock protein, Hsp42, which shows transient solubilization and phosphorylation, and is essential for the transformation of the cytoplasm during germination. Germinating spores therefore return to growth through the dissolution of protein assemblies, orchestrated in part by Hsp42 activity. The modulation of spores' molecular properties are likely key adaptive features of their exceptional survival capacities.
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Proteínas de Saccharomyces cerevisiae , Saccharomycetales , Proteoma/metabolismo , Solubilidad , Saccharomycetales/metabolismo , Esporas Fúngicas , Citoplasma/metabolismo , Saccharomyces cerevisiae/metabolismo , Esporas Bacterianas/metabolismo , Bacillus subtilis/metabolismo , Proteínas de Choque Térmico/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismoRESUMEN
As COVID-19 continues, an increasing number of patients develop long COVID symptoms varying in severity that last for weeks, months, or longer. Symptoms commonly include lingering loss of smell and taste, hearing loss, extreme fatigue, and "brain fog." Still, persistent cardiovascular and respiratory problems, muscle weakness, and neurologic issues have also been documented. A major problem is the lack of clear guidelines for diagnosing long COVID. Although some studies suggest that long COVID is due to prolonged inflammation after SARS-CoV-2 infection, the underlying mechanisms remain unclear. The broad range of COVID-19's bodily effects and responses after initial viral infection are also poorly understood. This workshop brought together multidisciplinary experts to showcase and discuss the latest research on long COVID and chronic inflammation that might be associated with the persistent sequelae following COVID-19 infection.
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COVID-19 , Síndrome Post Agudo de COVID-19 , Humanos , SARS-CoV-2 , Inflamación , Progresión de la EnfermedadRESUMEN
Ribosomes of Bacteroidia (formerly Bacteroidetes) fail to recognize Shine-Dalgarno (SD) sequences even though they harbor the anti-SD (ASD) of 16S rRNA. Inhibition of SD-ASD pairing is due to sequestration of the 3' tail of 16S rRNA in a pocket formed by bS21, bS18, and bS6 on the 30S platform. Interestingly, in many Flavobacteriales, the gene encoding bS21, rpsU, contains an extended SD sequence. In this work, we present genetic and biochemical evidence that bS21 synthesis in Flavobacterium johnsoniae is autoregulated via a subpopulation of ribosomes that specifically lack bS21. Mutation or depletion of bS21 in the cell increases translation of reporters with strong SD sequences, such as rpsU'-gfp, but has no effect on other reporters. Purified ribosomes lacking bS21 (or its C-terminal region) exhibit higher rates of initiation on rpsU mRNA and lower rates of initiation on other (SD-less) mRNAs than control ribosomes. The mechanism of autoregulation depends on extensive pairing between mRNA and 16S rRNA, and exceptionally strong SD sequences, with predicted pairing free energies of < -13 kcal/mol, are characteristic of rpsU across the Bacteroidota. This work uncovers a clear example of specialized ribosomes in bacteria.
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Proteínas Bacterianas , Flavobacterium , Proteínas Ribosómicas , Ribosomas , Flavobacterium/citología , Flavobacterium/metabolismo , Biosíntesis de Proteínas , Ribosomas/metabolismo , ARN Mensajero/metabolismo , ARN Ribosómico 16S/genética , Proteínas Bacterianas/metabolismo , Proteínas Ribosómicas/metabolismoRESUMEN
Diabetes is the leading cause of kidney disease that progresses to kidney failure. However, the key molecular and cellular pathways involved in diabetic kidney disease (DKD) pathogenesis are largely unknown. Here, we performed a comparative analysis of adult human kidneys by examining cell type-specific chromatin accessibility by single-nucleus ATAC-seq (snATAC-seq) and analyzing three-dimensional chromatin architecture via high-throughput chromosome conformation capture (Hi-C method) of paired samples. We mapped the cell type-specific and DKD-specific open chromatin landscape and found that genetic variants associated with kidney diseases were significantly enriched in the proximal tubule- (PT) and injured PT-specific open chromatin regions in samples from patients with DKD. BACH1 was identified as a core transcription factor of injured PT cells; its binding target genes were highly associated with fibrosis and inflammation, which were also key features of injured PT cells. Additionally, Hi-C analysis revealed global chromatin architectural changes in DKD, accompanied by changes in local open chromatin patterns. Combining the snATAC-seq and Hi-C data identified direct target genes of BACH1, and indicated that BACH1 binding regions showed increased chromatin contact frequency with promoters of their target genes in DKD. Thus, our multi-omics analysis revealed BACH1 target genes in injured PTs and highlighted the role of BACH1 as a novel regulator of tubular inflammation and fibrosis.
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Diabetes Mellitus , Nefropatías Diabéticas , Adulto , Humanos , Cromatina/genética , Nefropatías Diabéticas/genética , Cromosomas , Riñón , Fibrosis , Inflamación , Diabetes Mellitus/genéticaRESUMEN
Toxin- and drug-induced tubulointerstitial nephritis (TIN), characterized by interstitial infiltration of immune cells, frequently necessitates dialysis for patients due to irreversible fibrosis. However, agents modulating interstitial immune cells are lacking. Here, we addressed whether the housekeeping enzyme glutamyl-prolyl-transfer RNA synthetase 1 (EPRS1), responsible for attaching glutamic acid and proline to transfer RNA, modulates immune cell activity during TIN and whether its pharmacological inhibition abrogates fibrotic transformation. The immunological feature following TIN induction by means of an adenine-mixed diet was infiltration of EPRS1high T cells, particularly proliferating T and γδ T cells. The proliferation capacity of both CD4+ and CD8+ T cells, along with interleukin-17 production of γδ T cells, was higher in the kidneys of TIN-induced Eprs1+/+ mice than in the kidneys of TIN-induced Eprs1+/- mice. This discrepancy contributed to the fibrotic amelioration observed in kidneys of Eprs1+/- mice. TIN-induced fibrosis was also reduced in Rag1-/- mice adoptively transferred with Eprs1+/- T cells compared to the Rag1-/- mice transferred with Eprs1+/+ T cells. The use of an EPRS1-targeting small molecule inhibitor (bersiporocin) under clinical trials to evaluate its therapeutic potential against idiopathic pulmonary fibrosis alleviated immunofibrotic aggravation in TIN. EPRS1 expression was also observed in human kidney tissues and blood-derived T cells, and high expression was associated with worse patient outcomes. Thus, EPRS1 may emerge as a therapeutic target in toxin- and drug-induced TIN, modulating the proliferation and activity of infiltrated T cells.
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Aminoacil-ARNt Sintetasas , Nefritis Intersticial , Insuficiencia Renal , Animales , Humanos , Ratones , Aminoacil-ARNt Sintetasas/metabolismo , Linfocitos T CD8-positivos , Proliferación Celular , Fibrosis , Proteínas de Homeodominio , Nefritis Intersticial/inducido químicamente , Nefritis Intersticial/genética , Nefritis Intersticial/tratamiento farmacológicoRESUMEN
BACKGROUND: Nutrition plays a vital role in shaping the intestinal microbiome. However, many hospitalized children undergo periods of fasting during medical treatment. Changes to the small intestinal microbiota in early life in the setting of enteral deprivation have not been well described. OBJECTIVE: The aim of this study was to investigate the impact of enteral deprivation on the small intestinal mucosal microbiome and to identify factors that shape this interaction in infancy. METHODS: Intestinal biopsies were collected from proximal (fed) and distal (unfed) small bowel at the time of ostomy closure in children with a small intestinal enterostomy. Mucosal and luminal microbiome comparisons were performed including ß-diversity and differential abundance and correlations with clinical factors were analyzed. Host proteomics were compared between fed and unfed samples and correlated with microbiome parameters. Finally, microbial results were validated in another cohort of pediatric patients. RESULTS: Samples from 13 children (median age 84 d) were collected. Mucosal microbiome communities in the fed and unfed segments were strikingly similar [paired UniFrac distance (ß-diversity)], whereas luminal effluent differed significantly from fed samples (PERMANOVA, P = 0.003). Multivariate analysis revealed patient as the strongest predictor of the UniFrac distance. Environmental variables did not influence the intrapatient microbial dissimilarity. Host proteomics were similar intrapatient (paired fed-unfed Euclidian distance) and showed a correlation with the UniFrac distance (Spearman rho = 0.71, P < 0.001). Specific proteins and functional clusters were significantly different between paired samples, including lipid metabolism and intracellular trafficking, whereas no difference was seen in innate immune proteins. The microbiome results were validated in a different cohort with similar characteristics. CONCLUSION: We found the host to be the most dominant factor in the structure of the early life small intestinal mucosal microbiome. Nutrient deprivation was associated with specific changes in the host proteome. Further research is needed to better understand this host-microbe-nutrition interaction.
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Microbiota , Proteoma , Humanos , Niño , Anciano de 80 o más Años , Mucosa Intestinal , Intestinos , NutrientesRESUMEN
Condensation of water vapor on nonwetting surfaces, termed dropwise condensation, leads to rapid droplet removal and significantly improves heat transfer compared to wetting surfaces. However, the spatial distribution of heterogeneous nucleation sites during dropwise condensation is random. Furthermore, the low surface energy of the nonwetting substrate reduces the nucleation rate as predicted by classical nucleation theory. To achieve higher nucleation rates, biphilic surfaces having low nucleation energy barriers that rely on spatial heterogeneity of surface chemistry have been developed. Here, we use a robust method to create biphilic surfaces on flat and micropillar samples having various dimensions (pillar lengths: 10-15 µm, pillar heights: 0-15 µm) by utilizing lift-off microfabrication. Our fabrication approach leads to hydrophilic pillar tops and hydrophobic pillar sides and surrounding basal areas. To study water vapor condensation on the biphilic surfaces, we utilized optical microscopy in a controlled temperature and humidity environment. Interestingly, our studies show that while the majority of nucleation (≈100%) occurred only on the hydrophilic areas (pillar tops) for small pillar center-to-center spacing (pitch), the spatial control of heterogeneous nucleation broke down when the pitch increased. For larger pitches, we observed the nucleation of water droplets on the hydrophobic base in conjunction with hydrophilic pillar tops. Using theoretical models of vapor diffusion coupled with heat transfer and three-dimensional (3D) numerical simulations, we show that nucleation initiation on hydrophilic pillar tops leads to the formation of dry zones, preventing nucleation on hydrophobic regions. However, with increasing pitch, part of the hydrophobic region no longer feels the presence of the vapor depletion zone, resulting in subsequent nucleation at defect sites on the hydrophobic regions at the base. Our study offers insights into the fundamental limitations of biphilic condensation and offers avenues for their further improvement for applications such as boiling, icing, evaporation, and condensation.
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BACKGROUND: A small portion of patients are diagnosed with early gastric cancer (EGC) and undergo endoscopic submucosal dissection (ESD) at a young age. However, their clinical outcomes are rarely known. AIM: We investigated to identify the feasibility and clinical outcomes of ESD for EGC focusing on young patients. METHODS: We analyzed the clinical characteristics and outscomes of patients who had undergone ESD for the treatment of EGC at < 50 years of age. We enrolled patients who had been diagnosed with EGC and had undergone ESD between 2006 and 2020. We divided them by age as follows: ≤ 50 and > 50 years into the young age (YA) and other age (OA) groups, respectively. RESULTS: Altogether, 1681 patients underwent ESD for EGC (YA group: 124 [7.4%], OA group: 1557 [92.6%]). The YA group had less severe atrophy and more undifferentiated (37.1% vs. 13.9%, P < 0.001) and diffuse type (25% vs. 7.7%, P < 0.001) histology. The curative resection rate was not significantly different between the groups. However, among 1075 patients who had achieved curative resection and had been followed-up for > 12 months, the YA group had a lower incidence of MGN (5.2% vs. 17.5%, P = 0.004) and MGC (2.6% vs. 10.9%, P = 0.019) than those exhibited by the OA group. The YA group was a significant negative predictor of MGN (odds ratio [OR]: 2.983, 95% confidence interval [CI] 1.060-8.393, P = 0.038), and marginally negative predictor in MGC (OR: 3.909, 95% CI: 0.939-16.281, P = 0.061). CONCLUSION: ESD is a favorable and effective therapeutic modality for EGC patients aged < 50 years, once curative resection is achieved.
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Resección Endoscópica de la Mucosa , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/cirugía , Neoplasias Gástricas/patología , Resección Endoscópica de la Mucosa/métodos , Masculino , Femenino , Persona de Mediana Edad , Adulto , Pronóstico , Factores de Edad , Anciano , Estudios Retrospectivos , Resultado del Tratamiento , Mucosa Gástrica/cirugía , Mucosa Gástrica/patología , Estudios de FactibilidadRESUMEN
BACKGROUND: Diabetic kidney disease (DKD) stands as the predominant cause of chronic kidney disease and end-stage kidney disease. Its diverse range of manifestations complicates the treatment approach for patients. Although kidney biopsy is considered the gold standard for diagnosis, it lacks precision in predicting the progression of kidney dysfunction. Herein, we addressed whether the presence of glomerular crescents is linked to the outcomes in patients with biopsy-confirmed type 2 DKD. METHODS: We performed a retrospective evaluation, involving 327 patients diagnosed with biopsy-confirmed DKD in the context of type 2 diabetes, excluding cases with other glomerular diseases, from nine tertiary hospitals. Hazard ratios (HRs) were calculated using a Cox regression model to assess the risk of kidney disease progression, defined as either ≥ 50% decrease in estimated glomerular filtration rates or the development of end-stage kidney disease, based on the presence of glomerular crescents. RESULTS: Out of the 327 patients selected, ten patients had glomerular crescents observed in their biopsied tissues. Over the follow-up period (median of 19 months, with a maximum of 18 years), the crescent group exhibited a higher risk of kidney disease progression than the no crescent group, with an adjusted HR of 2.82 (1.32-6.06) (P = 0.008). The presence of heavy proteinuria was associated with an increased risk of developing glomerular crescents. CONCLUSION: The presence of glomerular crescents is indeed linked to the progression of type 2 DKD. Therefore, it is important to determine whether there is an additional immune-mediated glomerulonephritis requiring immunomodulation, and it may be prudent to monitor the histology and repeat a biopsy.
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Diabetes Mellitus Tipo 2 , Nefropatías Diabéticas , Progresión de la Enfermedad , Glomérulos Renales , Humanos , Nefropatías Diabéticas/patología , Estudios Retrospectivos , Masculino , Femenino , Persona de Mediana Edad , Diabetes Mellitus Tipo 2/complicaciones , Glomérulos Renales/patología , Anciano , Tasa de Filtración Glomerular , Estudios de Cohortes , Biopsia , Fallo Renal Crónico , Factores de RiesgoRESUMEN
OBJECTIVE: This study aims to evaluate the effect of an adaptive nutritional and educational intervention for patients on hemodialysis (HD) in a routine care setting, using real-world data from electronic health records. METHODS: Decentralized clinical trial of seven HD facilities recruited patients who have been on HD for over 3 months (N = 153) for an 8-week adaptive intervention protocol. Patients were divided into four groups: (1) control (2) education intervention (3) meal intervention (4) education and meal interventions. Educational contents were digitally delivered via mobile phones and premade meals tailored on laboratory findings were home-delivered. Changes in serum electrolytes and malnutrition inflammation score (MIS) were analyzed. RESULTS: Meal intervention statistically significantly stabilized serum phosphorus level (ß = -0.81 mg/dL, 95% confidence interval = [-1.40, -0.22]) at week 8, with increased likelihood of being within target serum value range (odds ratio = 1.21, 95% confidence interval = [1.04, 1.40]). Meal group showed better nutritional status (MIS = 3.65) than the education group (MIS = 5.10) at week 8 (adjusted p < .05). No significant changes were observed in serum potassium level, depression, and self-efficacy. CONCLUSION: It was demonstrated that an adaptive meal intervention in a real-world care setting may benefit serum phosphorus control and nutritional status of patients on HD, without negative effect on depression levels or self-efficacy. More work is needed to develop an effective educational intervention.
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Desnutrición , Estado Nutricional , Humanos , Inflamación/etiología , Desnutrición/prevención & control , Desnutrición/etiología , Fósforo , Diálisis Renal/efectos adversosRESUMEN
BACKGROUND: A poor diet is a risk factor for chronic obstructive pulmonary disease (COPD). The interaction between dietary factors and cigarette smoking in the development of COPD is unclear. We investigated the interactions between dietary patterns and smoking status on COPD-related outcomes. METHODS: We used data from the Anseong-Ansan cohort that has been followed for 20 years. A total of 6,221 individuals without COPD in the baseline survey were analyzed. Five dietary patterns were identified using a semi-quantitative food frequency questionnaire. Associations of dietary patterns with COPD and forced expiratory volume in 1 second (FEV1)/forced vital capacity (FVC) ratio in different strata of smoking status were evaluated using Cox regression and linear mixed models, respectively. RESULTS: The highest quartile of the "coffee" pattern (high coffee consumption) was associated with COPD (hazard ratio, 1.46; 95% confidence interval [CI], 1.03-2.08) and lower FEV1/FVC ratio (ß = -1.2%; 95% CI, -1.9% to -0.6%) using the lowest quartile as a reference for heavy smokers, but not light or never smokers (P value for interaction = 0.035 for COPD). Regarding the associations between various consumption levels of black coffee, combined coffee, and instant coffee and COPD, an association with COPD was only observed for instant coffee in heavy smokers. CONCLUSION: High instant coffee consumption is associated with COPD development in heavy smokers, but not in light or never smokers. This may be attributed to sugar and cream in instant coffee mixes.
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Fumar Cigarrillos , Enfermedad Pulmonar Obstructiva Crónica , Humanos , Café/efectos adversos , Estudios Prospectivos , Patrones Dietéticos , Enfermedad Pulmonar Obstructiva Crónica/epidemiología , Enfermedad Pulmonar Obstructiva Crónica/etiologíaRESUMEN
INTRODUCTION: Biomarkers of TDP-43 pathology are needed to distinguish frontotemporal lobar degeneration with TDP-43 pathology (FTLD-TDP) from phenotypically related disorders. While normal physiological TDP-43 is not a promising biomarker, low-resolution techniques have suggested truncated forms of TDP-43 may be specific to TDP-43 pathology. To advance biomarker efforts for FTLD-TDP, we employed a high-resolution structural technique to characterize TDP-43 post-translational modifications in FTLD-TDP. METHODS: High-resolution mass spectrometry was used to characterize TDP-43 proteoforms in brain tissue from FTLD-TDP, non-TDP-43 dementias and neuropathologically unaffected cases. Findings were then verified in a larger cohort of FTLD-TDP and non-TDP-43 dementias via targeted quantitative mass spectrometry. RESULTS: In the discovery phase, truncated TDP-43 identified FTLD-TDP with 85% sensitivity and 100% specificity. The verification phase revealed similar findings, with 83% sensitivity and 89% specificity. DISCUSSION: The concentration of truncated TDP-43 proteoforms-in particular, in vivo generated C-terminal fragments-have high diagnostic accuracy for FTLD-TDP. HIGHLIGHTS: Discovery: Truncated TDP-43 differentiates FTLD-TDP from related dementias. Verification: Truncated TDP-43 concentration has high accuracy for FTLD-TDP. TDP-43 proteoforms <28 kDa have highest discriminatory power for TDP-43 pathology.
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Demencia Frontotemporal , Degeneración Lobar Frontotemporal , Humanos , Demencia Frontotemporal/diagnóstico , Demencia Frontotemporal/genética , Proteínas de Unión al ADN/genética , Degeneración Lobar Frontotemporal/diagnóstico , Degeneración Lobar Frontotemporal/genética , Degeneración Lobar Frontotemporal/patología , BiomarcadoresRESUMEN
OBJECTIVE: To develop a preliminary risk scoring system to predict the prognosis of patients with diabetic forefoot ulcers based on the severity of vasculopathy and infection, which are the major risk factors for amputation. METHODS: Forefoot was defined as the distal part of the foot composed of the metatarsal bones and phalanges and associated soft tissue structures. The degree of vasculopathy was graded as V0, V1, or V2 according to transcutaneous partial oxygen tension values and toe pressure. The degree of infection was graded as I0, I1, or I2 according to tissue and bone biopsy culture results. The risk scores were calculated by adding the scores for the degree of vasculopathy and infection and ranged from 0 to 4. Wound healing outcomes were graded as healed without amputation, minor amputation, or major amputation. The authors evaluated wound healing outcomes according to risk scores. RESULTS: As the risk score increased, the proportion of patients who underwent both major and minor amputations increased (P < .001). In the multivariate logistic analysis, the odds ratios of amputation also increased as the risk score increased. Patients with a risk score of 4 were 75- and 19-fold more likely to undergo major and minor amputations, respectively, than patients with a risk score of 0 (P = .006 and P < .001). CONCLUSIONS: The risk score can be used as an indicator to predict the probability of amputation in patients with diabetic forefoot ulcers.
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Diabetes Mellitus , Pie Diabético , Humanos , Pie Diabético/diagnóstico , Pie Diabético/terapia , Úlcera , Pie , Cicatrización de Heridas , Amputación QuirúrgicaRESUMEN
Muscle-invasive urothelial carcinoma (MIUC) of the bladder shows highly aggressive tumor behavior, which has prompted the quest for robust biomarkers predicting invasion. To discover such biomarkers, we first employed high-throughput proteomic method and analyzed tissue biopsy cohorts from patients with bladder urothelial carcinoma (BUC), stratifying them according to their pT stage. Candidate biomarkers were selected through bioinformatic analysis, followed by validation. The latter comprised 2D and 3D invasion and migration assays, also a selection of external public datasets to evaluate mRNA expression and an in-house patient-derived tissue microarray (TMA) cohort to evaluate protein expression with immunohistochemistry (IHC). Our multilayered platform-based analysis identified tubulin beta 6 class V (TUBB6) as a promising prognostic biomarker predicting MIUC of the bladder. The in vitro 2D and 3D migration and invasion assays consistently showed that inhibition of TUBB6 mRNA significantly reduced cell migration and invasion ability in two BUC cell lines with aggressive phenotype (TUBB6 migration, P = .0509 and P < .0001; invasion, P = .0002 and P = .0044; TGFBI migration, P = .0214 and P = .0026; invasion, P < .0001 and P = .0001; T24 and J82, respectively). Validation through multiple public datasets, including The Cancer Genome Atlas (TCGA) and selected GSE (Genomic Spatial Event) databases, confirmed TUBB6 as a potential biomarker predicting MIUC. Further protein-based validation with our TMA cohort revealed concordant results, highlighting the clinical implication of TUBB6 expression in BUC patients (overall survival: P < .001). We propose TUBB6 as a novel IHC biomarker to predict invasion and poor prognosis, also select the optimal treatment in BUC patients.
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Carcinoma de Células Transicionales , Neoplasias de la Vejiga Urinaria , Humanos , Neoplasias de la Vejiga Urinaria/genética , Proteómica , Biomarcadores , Músculos , ARN Mensajero/genética , Pronóstico , Tubulina (Proteína)/genéticaRESUMEN
Viral protein genome-linked (VPg) protein plays an essential role in protein-primed replication of plus-stranded RNA viruses. VPg is covalently linked to the 5' end of the viral RNA genome via a phosphodiester bond typically at a conserved amino acid. Whereas most viruses have a single VPg, some viruses have multiple VPgs that are proposed to have redundant yet undefined roles in viral replication. Here, we use cricket paralysis virus (CrPV), a dicistrovirus that has four nonidentical copies of VPg, as a model to characterize the role of VPg copies in infection. Dicistroviruses contain two main open reading frames (ORFs) that are driven by distinct internal ribosome entry sites (IRESs). We systematically generated single and combinatorial deletions and mutations of VPg1 to VPg4 within the CrPV infectious clone and monitored viral yield in Drosophila S2 cells. Deletion of one to three VPg copies progressively decreased viral yield and delayed viral replication, suggesting a threshold number of VPgs for productive infection. Mass spectrometry analysis of CrPV VPg-linked RNAs revealed viral RNA linkage to either a serine or threonine in VPg, mutations of which in all VPgs attenuated infection. Mutating serine 4 in a single VPg abolished viral infection, indicating a dominant negative effect. Using viral minigenome reporters that monitor dicistrovirus 5' untranslated (UTR) and IRES translation revealed a relationship between VPg copy number and the ratio of distinct IRES translation activities. We uncovered a novel viral strategy whereby VPg copies in dicistrovirus genomes compensate for the relative IRES translation efficiencies to promote infection. IMPORTANCE Genetic duplication is exceedingly rare in small RNA viral genomes, as there is selective pressure to prevent RNA genomes from expanding. However, some small RNA viruses encode multiple copies of a viral protein, most notably an unusual viral protein that is linked to the viral RNA genome. Here, we investigate a family of viruses that contains multiple viral protein genome-linked proteins and reveal a novel viral strategy whereby viral protein copy number counterbalances differences in viral protein synthesis mechanisms.
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Dicistroviridae , Genoma Viral , Biosíntesis de Proteínas , Infecciones por Virus ARN , ARN Viral , Proteínas Virales , Regiones no Traducidas 5'/genética , Animales , Línea Celular , Dicistroviridae/genética , Dicistroviridae/metabolismo , Drosophila/citología , Drosophila/virología , Genoma Viral/genética , Sitios Internos de Entrada al Ribosoma/genética , Mutación , Infecciones por Virus ARN/virología , ARN Viral/genética , Serina/metabolismo , Treonina/metabolismo , Carga Viral , Proteínas Virales/biosíntesis , Proteínas Virales/genética , Proteínas Virales/metabolismoRESUMEN
Radiation-induced sarcoma (RIS) is a rare but serious late complication arising from radiotherapy. Despite unfavorable clinical outcomes, the genomic footprints of ionizing radiation in RIS development remain largely unknown. Hence, this study aimed to characterize RIS genomes and the genomic alterations in them. We analyzed whole-genome sequencing in 11 RIS genomes matched with normal genomes to identify somatic alterations potentially associated with RIS development. Furthermore, the abundance of mutations, mutation signatures, and structural variants in RIS were compared with those in radiation-naïve spontaneous sarcomas. The mutation abundance in RIS genomes, including one hypermutated genome, was variable. Cancer-related genes might show different types of genomic alterations. For instance, NF1, NF2, NOTCH1, NOTCH2, PIK3CA, RB1, and TP53 showed singleton somatic mutations; MYC, CDKN2A, RB1, and NF1 showed recurrent copy number alterations; and NF2, ARID1B, and RAD51B showed recurrent structural variations. The genomic footprints of nonhomologous end joining are prevalent at indels of RIS genomes compared with those in spontaneous sarcoma genomes, representing the genomic hallmark of RIS genomes. In addition, frequent chromothripsis was identified along with predisposing germline variants in the DNA-damage-repair pathways in RIS genomes. The characterization of RIS genomes on a whole-genome sequencing scale highlighted that the nonhomologous end joining pathway was associated with tumorigenesis, and it might pave the way for the development of advanced diagnostic and therapeutic strategies for RIS.
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Sarcoma , Neoplasias de los Tejidos Blandos , Humanos , Mutación , Oncogenes , Sarcoma/genética , Mutación de Línea Germinal , Neoplasias de los Tejidos Blandos/genética , ADNRESUMEN
BACKGROUND: Breast cancer brain metastasis (BCBM) is a growing therapeutic challenge and clinical concern. Stromal cancer-associated fibroblasts (CAFs) are crucial factors in the modulation of tumorigeneses and metastases. Herein, we investigated the relationship between the expression of stromal CAF markers in metastatic sites, platelet-derived growth factor receptor-beta (PDGFR-ß), and alpha-smooth muscle actin (α-SMA) and the clinical and prognostic variables in BCBM patients. METHODS: Immunohistochemistry (IHC) of the stromal expression of PDGFR-ß and α-SMA was performed on 50 cases of surgically resected BCBM. The expression of the CAF markers was analyzed in the context of clinico-pathological characteristics. RESULTS: Expression of PDGFR-ß and α-SMA was lower in the triple-negative (TN) subtype than in other molecular subtypes (p = 0.073 and p = 0.016, respectively). And their expressions were related to a specific pattern of CAF distribution (PDGFR-ß, p = 0.009; α-SMA, p = 0.043) and BM solidity (p = 0.009 and p = 0.002, respectively). High PDGFR-ß expression was significantly related to longer recurrence-free survival (RFS) (p = 0.011). TN molecular subtype and PDGFR-ß expression were independent prognostic factors of recurrence-free survival (p = 0.029 and p = 0.030, respectively) and TN molecular subtype was an independent prognostic factor of overall survival (p < 0.001). CONCLUSIONS: Expression of PDGFR-ß in the stroma of BM was associated with RFS in BCBM patients, and the clinical implication was uniquely linked to the low expression of PDGFR-ß and α-SMA in the aggressive form of the TN subtype.
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Neoplasias Encefálicas , Neoplasias de la Mama , Femenino , Humanos , Actinas/metabolismo , Biomarcadores de Tumor/metabolismo , Neoplasias de la Mama/patología , Relevancia Clínica , Fibroblastos/metabolismo , Pronóstico , Receptor beta de Factor de Crecimiento Derivado de Plaquetas/genética , Receptor beta de Factor de Crecimiento Derivado de Plaquetas/metabolismo , Neoplasias Encefálicas/secundarioRESUMEN
Hepatic stellate cells (HSCs) play an important role in liver fibrosis; however, owing to the heterogeneity and limited supply of primary HSCs, the development of in vitro liver fibrosis models has been impeded. In this study, we established and characterized a novel human HSC line (LSC-1), and applied it to various types of three-dimensional (3D) co-culture systems with differentiated HepaRG cells. Furthermore, we compared LSC-1 with a commercially available HSC line on conventional monolayer culture. LSC-1 exhibited an overall upregulation of the expression of fibrogenic genes along with increased levels of matrix and adhesion proteins, suggesting a myofibroblast-like or transdifferentiated state. However, activated states reverted to a quiescent-like phenotype when cultured in different 3D culture formats with a relatively soft microenvironment. Additionally, LSC-1 exerted an overall positive effect on co-cultured differentiated HepaRG, which significantly increased hepatic functionality upon long-term cultivation compared with that achieved with other HSC line. In 3D spheroid culture, LSC-1 exhibited enhanced responsiveness to transforming growth factor beta 1 exposure that is caused by a different matrix-related protein expression mechanism. Therefore, the LSC-1 line developed in this study provides a reliable candidate model that can be used to address unmet needs, such as development of antifibrotic therapies.