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1.
Cell ; 163(5): 1204-1213, 2015 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-26582133

RESUMEN

Duchenne muscular dystrophy (DMD), caused by mutations at the dystrophin gene, is the most common form of muscular dystrophy. There is no cure for DMD and current therapeutic approaches to restore dystrophin expression are only partially effective. The absence of dystrophin in muscle results in dysregulation of signaling pathways, which could be targets for disease therapy and drug discovery. Previously, we identified two exceptional Golden Retriever muscular dystrophy (GRMD) dogs that are mildly affected, have functional muscle, and normal lifespan despite the complete absence of dystrophin. Now, our data on linkage, whole-genome sequencing, and transcriptome analyses of these dogs compared to severely affected GRMD and control animals reveals that increased expression of Jagged1 gene, a known regulator of the Notch signaling pathway, is a hallmark of the mild phenotype. Functional analyses demonstrate that Jagged1 overexpression ameliorates the dystrophic phenotype, suggesting that Jagged1 may represent a target for DMD therapy in a dystrophin-independent manner. PAPERCLIP.


Asunto(s)
Proteínas de Unión al Calcio/genética , Modelos Animales de Enfermedad , Péptidos y Proteínas de Señalización Intercelular/genética , Proteínas de la Membrana/genética , Distrofia Muscular de Duchenne/genética , Animales , Proliferación Celular , Enfermedades de los Perros/genética , Perros , Distrofina/deficiencia , Distrofina/genética , Femenino , Estudio de Asociación del Genoma Completo , Proteína Jagged-1 , Masculino , Ratones , Distrofia Muscular Animal/genética , Linaje , Penetrancia , Proteínas Serrate-Jagged , Transcriptoma , Pez Cebra , Proteínas de Pez Cebra
2.
Brief Bioinform ; 25(2)2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38279652

RESUMEN

Cleavage Under Targets and Release Using Nuclease (CUT&RUN) is a recent development for epigenome mapping, but its unique methodology can hamper proper quantitative analyses. As traditional normalization approaches have been shown to be inaccurate, we sought to determine endogenous normalization factors based on the human genome regions of constant nonspecific signal. This constancy was determined by applying Shannon's information entropy, and the set of normalizer regions, which we named the 'Greenlist', was extensively validated using publicly available datasets. We demonstrate here that the greenlist normalization outperforms the current top standards, and remains consistent across different experimental setups, cell lines and antibodies; the approach can even be applied to different species or to CUT&Tag. Requiring no additional experimental steps and no added cost, this approach can be universally applied to CUT&RUN experiments to greatly minimize the interference of technical variation over the biological epigenome changes of interest.


Asunto(s)
Epigenoma , Genómica , Humanos , Genoma
3.
Mol Biol Evol ; 41(7)2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38913688

RESUMEN

The outstanding human cognitive capacities are computed in the cerebral cortex, a mammalian-specific brain region and the place of massive biological innovation. Long noncoding RNAs have emerged as gene regulatory elements with higher evolutionary turnover than mRNAs. The many long noncoding RNAs identified in neural tissues make them candidates for molecular sources of cerebral cortex evolution and disease. Here, we characterized the genomic and cellular shifts that occurred during the evolution of the long noncoding RNA repertoire expressed in the developing cerebral cortex and explored putative roles for these long noncoding RNAs in the evolution of the human brain. Using transcriptomics and comparative genomics, we comprehensively annotated the cortical transcriptomes of humans, rhesus macaques, mice, and chickens and classified human cortical long noncoding RNAs into evolutionary groups as a function of their predicted minimal ages. Long noncoding RNA evolutionary groups showed differences in expression levels, splicing efficiencies, transposable element contents, genomic distributions, and transcription factor binding to their promoters. Furthermore, older long noncoding RNAs showed preferential expression in germinative zones, outer radial glial cells, and cortical inhibitory (GABAergic) neurons. In comparison, younger long noncoding RNAs showed preferential expression in cortical excitatory (glutamatergic) neurons, were enriched in primate and human-specific gene co-expression modules, and were dysregulated in neurodevelopmental disorders. These results suggest different evolutionary routes for older and younger cortical long noncoding RNAs, highlighting old long noncoding RNAs as a possible source of molecular evolution of conserved developmental programs; conversely, we propose that the de novo expression of primate- and human-specific young long noncoding RNAs is a putative source of molecular evolution and dysfunction of cortical excitatory neurons, warranting further investigation.


Asunto(s)
Corteza Cerebral , Macaca mulatta , Neuronas , ARN Largo no Codificante , ARN Largo no Codificante/genética , Humanos , Corteza Cerebral/metabolismo , Animales , Ratones , Neuronas/metabolismo , Pollos/genética , Evolución Molecular , Transcriptoma
4.
PLoS Pathog ; 19(5): e1011369, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37146077

RESUMEN

The trematode parasite Schistosoma mansoni causes schistosomiasis, which affects over 200 million people worldwide. Schistosomes are dioecious, with egg laying depending on the females' obligatory pairing with males. Long non-coding RNAs (lncRNAs) are transcripts longer than 200 nucleotides with low or no protein-coding potential that have been involved in other species with reproduction, stem cell maintenance, and drug resistance. In S. mansoni, we recently showed that the knockdown of one lncRNA affects the pairing status of these parasites. Here, we re-analyzed public RNA-Seq data from paired and unpaired adult male and female worms and their gonads, obtained from mixed-sex or single-sex cercariae infections, and found thousands of differentially expressed pairing-dependent lncRNAs among the 23 biological samples that were compared. The expression levels of selected lncRNAs were validated by RT-qPCR using an in vitro unpairing model. In addition, the in vitro silencing of three selected lncRNAs showed that knockdown of these pairing-dependent lncRNAs reduced cell proliferation in adult worms and their gonads, and are essential for female vitellaria maintenance, reproduction, and/or egg development. Remarkably, in vivo silencing of each of the three selected lncRNAs significantly reduced worm burden in infected mice by 26 to 35%. Whole mount in situ hybridization experiments showed that these pairing-dependent lncRNAs are expressed in reproductive tissues. These results show that lncRNAs are key components intervening in S. mansoni adult worm homeostasis, which affects pairing status and survival in the mammalian host, thus presenting great potential as new therapeutic target candidates.


Asunto(s)
Parásitos , ARN Largo no Codificante , Esquistosomiasis mansoni , Masculino , Femenino , Animales , Ratones , Schistosoma mansoni/genética , ARN Largo no Codificante/genética , Fertilidad/genética , Reproducción , Parásitos/genética , Esquistosomiasis mansoni/parasitología , Mamíferos
5.
Hum Mol Genet ; 29(9): 1465-1475, 2020 06 03.
Artículo en Inglés | MEDLINE | ID: mdl-32280986

RESUMEN

Amyotrophic lateral sclerosis type 8 (ALS8) is an autosomal dominant form of ALS, which is caused by pathogenic variants in the VAPB gene. Here we investigated five ALS8 patients, classified as 'severe' and 'mild' from a gigantic Brazilian kindred, carrying the same VAPB mutation but displaying different clinical courses. Copy number variation and whole exome sequencing analyses in such individuals ruled out previously described genetic modifiers of pathogenicity. After deriving induced pluripotent stem cells (iPSCs) for each patient (N = 5) and controls (N = 3), motor neurons were differentiated, and high-throughput RNA-Seq gene expression measurements were performed. Functional cell death and oxidative metabolism assays were also carried out in patients' iPSC-derived motor neurons. The degree of cell death and mitochondrial oxidative metabolism were similar in iPSC-derived motor neurons from mild patients and controls and were distinct from those of severe patients. Similar findings were obtained when RNA-Seq from such cells was performed. Overall, 43 genes were upregulated and 66 downregulated in the two mild ALS8 patients when compared with severe ALS8 individuals and controls. Interestingly, significantly enriched pathways found among differentially expressed genes, such as protein translation and protein targeting to the endoplasmic reticulum (ER), are known to be associated with neurodegenerative processes. Taken together, the mitigating mechanisms here presented appear to maintain motor neuron survival by keeping translational activity and protein targeting to the ER in such cells. As ALS8 physiopathology has been associated with proteostasis mechanisms in ER-mitochondria contact sites, such differentially expressed genes appear to relate to the bypass of VAPB deficiency.


Asunto(s)
Esclerosis Amiotrófica Lateral/genética , Mitocondrias/genética , Degeneración Nerviosa/genética , Proteínas de Transporte Vesicular/genética , Anciano , Esclerosis Amiotrófica Lateral/metabolismo , Esclerosis Amiotrófica Lateral/patología , Diferenciación Celular/genética , Retículo Endoplásmico/genética , Femenino , Regulación de la Expresión Génica/genética , Humanos , Células Madre Pluripotentes Inducidas/metabolismo , Células Madre Pluripotentes Inducidas/patología , Masculino , Persona de Mediana Edad , Mitocondrias/metabolismo , Neuronas Motoras/metabolismo , Neuronas Motoras/patología , Degeneración Nerviosa/patología , Estrés Oxidativo/genética , RNA-Seq , Proteínas de Transporte Vesicular/deficiencia
6.
Parasitol Res ; 121(4): 1091-1115, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34859292

RESUMEN

Long non-coding RNAs (lncRNAs) emerged in the past 20 years due to massive amounts of scientific data regarding transcriptomic analyses. They have been implicated in a plethora of cellular processes in higher eukaryotes. However, little is known about lncRNA possible involvement in parasitic diseases, with most studies only detecting their presence in parasites of human medical importance. Here, we review the progress on lncRNA studies and their functions in protozoans and helminths. In addition, we show an example of knockdown of one lncRNA in Schistosoma mansoni, SmLINC156349, which led to in vitro parasite adhesion, motility, and pairing impairment, with a 20% decrease in parasite viability and 33% reduction in female oviposition. Other observed phenotypes were a decrease in the proliferation rate of both male and female worms and their gonads, and reduced female lipid and vitelline droplets that are markers for well-developed vitellaria. Impairment of female worms' vitellaria in SmLINC156349-silenced worms led to egg development deficiency. All those results demonstrate the great potential of the tools and methods to characterize lncRNAs as potential new therapeutic targets. Further, we discuss the challenges and limitations of current methods for studying lncRNAs in parasites and possible solutions to overcome them, and we highlight the future directions of this exciting field.


Asunto(s)
Helmintos , Parásitos , Enfermedades Parasitarias , ARN Largo no Codificante , Animales , Femenino , Perfilación de la Expresión Génica , Helmintos/genética , Masculino , Parásitos/genética , ARN Largo no Codificante/genética , Schistosoma mansoni/genética
7.
Cell Commun Signal ; 19(1): 5, 2021 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-33430890

RESUMEN

BACKGROUND: Androgen receptor (AR) and polycomb repressive complex 2 (PRC2) are known to co-occupy the loci of genes that are downregulated by androgen-stimulus. Long intergenic non-coding RNA (lincRNA) PVT1 is an overexpressed oncogene that is associated with AR in LNCaP prostate cancer cells, and with PRC2 in HeLa and many other types of cancer cells. The possible involvement of PVT1 in mediating androgen-induced gene expression downregulation in prostate cancer has not been explored. METHODS: LNCaP cell line was used. Native RNA-binding-protein immunoprecipitation with anti-AR or anti-EZH2 was followed by RT-qPCR with primers for PVT1. Knockdown of PVT1 with specific GapmeRs (or a control with scrambled GapmeR) was followed by differentially expressed genes (DEGs) determination with Agilent microarrays and with Significance Analysis of Microarrays statistical test. DEGs were tested as a tumor risk classifier with a machine learning Random Forest algorithm run with gene expression data from all TCGA-PRAD (prostate adenocarcinoma) tumors as input. ChIP-qPCR was performed for histone marks at the promoter of one DEG. RESULTS: We show that PVT1 knockdown in androgen-stimulated LNCaP cells caused statistically significant expression upregulation/downregulation of hundreds of genes. Interestingly, PVT1 knockdown caused upregulation of 160 genes that were repressed by androgen, including a significantly enriched set of tumor suppressor genes, and among them FAS, NOV/CCN3, BMF, HRK, IFIT2, AJUBA, DRAIC and TNFRSF21. A 121-gene-set (out of the 160) was able to correctly predict the classification of all 293 intermediate- and high-risk TCGA-PRAD tumors, with a mean ROC area under the curve AUC = 0.89 ± 0.04, pointing to the relevance of these genes in cancer aggressiveness. Native RIP-qPCR in LNCaP showed that PVT1 was associated with EZH2, a component of PRC2. PVT1 knockdown followed by ChIP-qPCR showed significant epigenetic remodeling at the enhancer and promoter regions of tumor suppressor gene NOV, one of the androgen-repressed genes that were upregulated upon PVT1 silencing. CONCLUSIONS: Overall, we provide first evidence that PVT1 was involved in signaling a genome-wide androgen-dependent transcriptional repressive program of tumor suppressor protein-coding genes in prostate cancer cells. Identification of transcriptional inhibition of tumor suppressor genes by PVT1 highlights the pathway to the investigation of mechanisms that lie behind the oncogenic role of PVT1 in cancer. Video Abstract.


Asunto(s)
Regulación Neoplásica de la Expresión Génica , Neoplasias de la Próstata/genética , ARN Largo no Codificante/genética , Andrógenos , Línea Celular Tumoral , Proteína Potenciadora del Homólogo Zeste 2/genética , Humanos , Estimación de Kaplan-Meier , Masculino , Neoplasias de la Próstata/mortalidad , Receptores Androgénicos/genética , Transducción de Señal , Proteínas Supresoras de Tumor/genética
8.
Alzheimers Dement ; 17(11): 1818-1831, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-33881211

RESUMEN

INTRODUCTION: Dementia has been associated with COVID-19 prevalence, but whether this reflects higher infection, older age of patients, or disease severity remains unclear. METHODS: We investigated a cohort of 12,863 UK Biobank community-dwelling individuals > 65 years old (1814 individuals ≥ 80 years old) tested for COVID-19. Individuals were stratified by age to account for age as a confounder. Risk factors were analyzed for COVID-19-positive diagnosis, hospitalization, and death. RESULTS: All-cause dementia, Alzheimer's disease (AD), and Parkinson's disease (PD) were associated with COVID-19-positive diagnosis, and all-cause dementia and AD remained associated in individuals ≥ 80 years old. All-cause dementia, AD, or PD were not risk factors for overall hospitalization, but increased the risk of hospitalization of COVID-19 patients. All-cause dementia and AD increased the risk of COVID-19-related death, and all-cause dementia was uniquely associated with increased death in ≥ 80-year-old patients. DISCUSSION: All-cause dementia and AD are age-independent risk factors for disease severity and death in COVID-19.


Asunto(s)
COVID-19/mortalidad , Demencia/epidemiología , Factores de Edad , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/complicaciones , Enfermedad de Alzheimer/epidemiología , COVID-19/complicaciones , Comorbilidad , Demencia/complicaciones , Femenino , Hospitalización , Humanos , Vida Independiente , Pacientes Internos , Masculino , Enfermedad de Parkinson/complicaciones , Enfermedad de Parkinson/epidemiología , Prevalencia , Estudios Prospectivos , Factores de Riesgo , Índice de Severidad de la Enfermedad , Reino Unido/epidemiología
9.
Phytopathology ; 110(11): 1751-1755, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32520631

RESUMEN

Xylella fastidiosa subsp. pauca, once confined to South America and infecting mainly citrus and coffee plants, has been found to be associated with other hosts and in other geographic regions. We present high-quality draft genome sequences of X. fastidiosa subsp. pauca strains J1a12, B111, U24D, and XRB isolated from citrus plants in Brazil, strain Fb7 isolated from a citrus plant in Argentina and strains 3124, Pr8x, and Hib4 isolated, respectively, from coffee, plum, and hibiscus plants in Brazil. Sequencing was performed using Roche 454-GS FLX, MiSeq-Illumina or Pacific Biosciences platforms. These high-quality genome assemblies will be useful for further studies about the genomic diversity, evolution, and biology of X. fastidiosa.


Asunto(s)
Citrus , Hibiscus , Prunus domestica , Xylella , Argentina , Brasil , Café , Enfermedades de las Plantas , Xylella/genética
10.
Proc Natl Acad Sci U S A ; 114(9): E1587-E1596, 2017 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-28193876

RESUMEN

Infection of pregnant women by Asian lineage strains of Zika virus (ZIKV) has been linked to brain abnormalities in their infants, yet it is uncertain when during pregnancy the human conceptus is most vulnerable to the virus. We have examined two models to study susceptibility of human placental trophoblast to ZIKV: cytotrophoblast and syncytiotrophoblast derived from placental villi at term and colonies of trophoblast differentiated from embryonic stem cells (ESC). The latter appear to be analogous to the primitive placenta formed during implantation. The cells from term placentas, which resist infection, do not express genes encoding most attachment factors implicated in ZIKV entry but do express many genes associated with antiviral defense. By contrast, the ESC-derived trophoblasts possess a wide range of attachment factors for ZIKV entry and lack components of a robust antiviral response system. These cells, particularly areas of syncytiotrophoblast within the colonies, quickly become infected, produce infectious virus and undergo lysis within 48 h after exposure to low titers (multiplicity of infection > 0.07) of an African lineage strain (MR766 Uganda: ZIKVU) considered to be benign with regards to effects on fetal development. Unexpectedly, lytic effects required significantly higher titers of the presumed more virulent FSS13025 Cambodia (ZIKVC). Our data suggest that the developing fetus might be most vulnerable to ZIKV early in the first trimester before a protective zone of mature villous trophoblast has been established. Additionally, MR766 is highly trophic toward primitive trophoblast, which may put the early conceptus of an infected mother at high risk for destruction.


Asunto(s)
Placenta/virología , Trofoblastos/virología , Infección por el Virus Zika/virología , Virus Zika/patogenicidad , Cambodia , Células Cultivadas , Células Madre Embrionarias/virología , Femenino , Humanos , Embarazo , Primer Trimestre del Embarazo/fisiología , Uganda
11.
Proc Natl Acad Sci U S A ; 114(23): 6080-6085, 2017 06 06.
Artículo en Inglés | MEDLINE | ID: mdl-28533404

RESUMEN

Duchenne muscular dystrophy (DMD) is a progressive muscle wasting disease caused by X-linked inherited mutations in the DYSTROPHIN (DMD) gene. Absence of dystrophin protein from the sarcolemma causes severe muscle degeneration, fibrosis, and inflammation, ultimately leading to cardiorespiratory failure and premature death. Although there are several promising strategies under investigation to restore dystrophin protein expression, there is currently no cure for DMD, and identification of genetic modifiers as potential targets represents an alternative therapeutic strategy. In a Brazilian golden retriever muscular dystrophy (GRMD) dog colony, two related dogs demonstrated strikingly mild dystrophic phenotypes compared with those typically observed in severely affected GRMD dogs despite lacking dystrophin. Microarray analysis of these "escaper" dogs revealed reduced expression of phosphatidylinositol transfer protein-α (PITPNA) in escaper versus severely affected GRMD dogs. Based on these findings, we decided to pursue investigation of modulation of PITPNA expression on dystrophic pathology in GRMD dogs, dystrophin-deficient sapje zebrafish, and human DMD myogenic cells. In GRMD dogs, decreased expression of Pitpna was associated with increased phosphorylated Akt (pAkt) expression and decreased PTEN levels. PITPNA knockdown by injection of morpholino oligonucleotides in sapje zebrafish also increased pAkt, rescued the abnormal muscle phenotype, and improved long-term sapje mutant survival. In DMD myotubes, PITPNA knockdown by lentiviral shRNA increased pAkt and increased myoblast fusion index. Overall, our findings suggest PIPTNA as a disease modifier that accords benefits to the abnormal signaling, morphology, and function of dystrophic skeletal muscle, and may be a target for DMD and related neuromuscular diseases.


Asunto(s)
Distrofia Muscular de Duchenne/metabolismo , Proteínas de Transferencia de Fosfolípidos/metabolismo , Proteínas de Transferencia de Fosfolípidos/fisiología , Animales , Línea Celular , Modelos Animales de Enfermedad , Perros , Distrofina/genética , Distrofina/metabolismo , Humanos , Células Musculares/fisiología , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/metabolismo , Distrofia Muscular Animal/genética , Distrofia Muscular de Duchenne/fisiopatología , Mutación , Fosforilación , Proteínas Proto-Oncogénicas c-akt , Pez Cebra/metabolismo
12.
Biochim Biophys Acta Mol Basis Dis ; 1863(2): 450-461, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27840303

RESUMEN

New drug development for neoplasm treatment is nowadays based on molecular targets that participate in the disease pathogenesis and tumor phenotype. Herein, we describe a new specific pharmacological hematopoietic cell kinase (HCK) inhibitor (iHCK-37) that was able to reduce PI3K/AKT and MAPK/ERK pathways activation after erythropoietin induction in cells with high HCK expression: iHCK-37 treatment increased leukemic cells death and, very importantly, did not affect normal hematopoietic stem cells. We also present evidence that HCK, one of Src kinase family (SFK) member, regulates early-stage erythroid cell differentiation by acting as an upstream target of a frequently deregulated pathway in hematologic neoplasms, PI3K/AKT and MAPK/ERK. Notably, HCK levels were highly increased in stem cells from patients with some diseases, as Myelodysplastic Syndromes (MDS) and Acute Myeloid Leukemia (AML), that are associated with ineffective erythropoiesis These discoveries support the exploration of the new pharmacological iHCK-37 in future preclinical and clinical studies.


Asunto(s)
Inhibidores Enzimáticos/farmacología , Eritropoyetina/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-hck/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-hck/metabolismo , Transducción de Señal/efectos de los fármacos , Adulto , Anciano , Muerte Celular/efectos de los fármacos , Eritropoyesis/efectos de los fármacos , Femenino , Factor de Transcripción GATA1/metabolismo , Células Madre Hematopoyéticas/efectos de los fármacos , Células Madre Hematopoyéticas/metabolismo , Humanos , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/metabolismo , Masculino , Persona de Mediana Edad , Terapia Molecular Dirigida , Síndromes Mielodisplásicos/tratamiento farmacológico , Síndromes Mielodisplásicos/metabolismo , Adulto Joven
13.
Biochim Biophys Acta Gen Subj ; 1861(1 Pt A): 3490-3497, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27639541

RESUMEN

BACKGROUND: The Micro-Exon Gene-14 (MEG-14) displays a remarkable structure that allows the generation of antigenic variation in Schistosomes. Previous studies showed that the soluble portion of the MEG-14 protein displays features of an intrinsically disordered protein and is expressed exclusively in the parasite esophageal gland. These features indicated a potential for interaction with host proteins present in the plasma and cells from ingested blood. METHODS: A yeast two-hybrid experiment using as bait the soluble domain of Schistosoma mansoni MEG-14 (sMEG-14) against a human leukocyte cDNA library was performed. Pull-down and surface plasmon resonance (SPR) experiments were used to validate the interaction between sMEG-14 and human S100A9. Synchrotron radiation circular dichroism (SRCD) were used to detect structural changes upon interaction between sMEG-14 and human S100A9. Feeding of live parasites with S100A9 attached to a fluorophore allowed the tracking of the fate of this protein in the parasite digestive system. RESULTS: S100A9 interacted with sMEG-14 consistently in yeast two-hybrid assay, pull-down and SPR experiments. SRCD suggested that MEG-14 acquired a more regular structure as a result of the interaction with S100A9. Accumulation of recombinant S100A9 in the parasite's esophageal gland, when ingested by live worms suggests that such interaction may occur in vivo. CONCLUSION: S100A9, a protein previously described to be involved in modulation of inflammatory response, was found to interact with sMEG-14. GENERAL SIGNIFICANCE: Our results allow proposing a mechanism involving MEG-14 for the parasite to block inflammatory signaling, which would occur upon release of S100A9 when ingested blood cells are lysed.


Asunto(s)
Esófago/metabolismo , Inflamación/patología , Proteínas Protozoarias/metabolismo , Proteínas S100/metabolismo , Schistosoma mansoni/metabolismo , Empalme Alternativo/genética , Animales , Dicroismo Circular , Cricetinae , Electroforesis en Gel de Poliacrilamida , Humanos , Unión Proteica , Estructura Secundaria de Proteína , Resonancia por Plasmón de Superficie , Técnicas del Sistema de Dos Híbridos
14.
Tumour Biol ; 37(10): 13855-13870, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27485113

RESUMEN

Breast carcinoma (BC) corresponds to 23 % of all cancers in women, with 1.38 million new cases and 460,000 deaths worldwide annually. Despite the significant advances in the identification of molecular markers and different modalities of treatment for primary BC, the ability to predict its metastatic behavior is still limited. The purpose of this study was to identify novel molecular markers associated with distinct clinical outcomes in a Brazilian cohort of BC patients. We generated global gene expression profiles using tumor samples from 24 patients with invasive ductal BC who were followed for at least 5 years, including a group of 15 patients with favorable outcomes and another with nine patients who developed metastasis. We identified a set of 58 differentially expressed genes (p ≤ 0.01) between the two groups. The prognostic value of this metastasis signature was corroborated by its ability to stratify independent BC patient datasets according to disease-free survival and overall survival. The upregulation of B3GNT7, PPM1D, TNKS2, PHB, and GTSE1 in patients with poor outcomes was confirmed by quantitative reverse transcription polymerase chain reaction (RT-qPCR) in an independent sample of patients with BC (47 with good outcomes and eight that presented metastasis). The expression of BCL2-associated agonist of cell death (BAD) protein was determined in 1276 BC tissue samples by immunohistochemistry and was consistent with the reduced BAD mRNA expression levels in metastatic cases, as observed in the oligoarray data. These findings point to novel prognostic markers that can distinguish breast carcinomas with metastatic potential from those with favorable outcomes.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Neoplasias de la Mama/patología , Carcinoma Ductal de Mama/secundario , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/genética , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Carcinoma Ductal de Mama/genética , Carcinoma Ductal de Mama/metabolismo , Femenino , Estudios de Seguimiento , Humanos , Técnicas para Inmunoenzimas , Proteínas Asociadas a Microtúbulos/genética , Proteínas Asociadas a Microtúbulos/metabolismo , Persona de Mediana Edad , N-Acetilglucosaminiltransferasas/genética , N-Acetilglucosaminiltransferasas/metabolismo , Clasificación del Tumor , Invasividad Neoplásica , Metástasis de la Neoplasia , Estadificación de Neoplasias , Pronóstico , Prohibitinas , Proteína Fosfatasa 2C/genética , Proteína Fosfatasa 2C/metabolismo , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Proteínas Represoras/genética , Proteínas Represoras/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Tasa de Supervivencia , Tanquirasas/genética , Tanquirasas/metabolismo , Adulto Joven
15.
Nucleic Acids Res ; 42(13): 8343-55, 2014 07.
Artículo en Inglés | MEDLINE | ID: mdl-24992962

RESUMEN

BCL-X mRNA alternative splicing generates pro-apoptotic BCL-XS or anti-apoptotic BCL-XL gene products and the mechanism that regulates splice shifting is incompletely understood. We identified and characterized a long non-coding RNA (lncRNA) named INXS, transcribed from the opposite genomic strand of BCL-X, that was 5- to 9-fold less abundant in tumor cell lines from kidney, liver, breast and prostate and in kidney tumor tissues compared with non-tumors. INXS is an unspliced 1903 nt-long RNA, is transcribed by RNA polymerase II, 5'-capped, nuclear enriched and binds Sam68 splicing-modulator. Three apoptosis-inducing agents increased INXS lncRNA endogenous expression in the 786-O kidney tumor cell line, increased BCL-XS/BCL-XL mRNA ratio and activated caspases 3, 7 and 9. These effects were abrogated in the presence of INXS knockdown. Similarly, ectopic INXS overexpression caused a shift in splicing toward BCL-XS and activation of caspases, thus leading to apoptosis. BCL-XS protein accumulation was detected upon INXS overexpression. In a mouse xenograft model, intra-tumor injections of an INXS-expressing plasmid caused a marked reduction in tumor weight, and an increase in BCL-XS isoform, as determined in the excised tumors. We revealed an endogenous lncRNA that induces apoptosis, suggesting that INXS is a possible target to be explored in cancer therapies.


Asunto(s)
Apoptosis , ARN Largo no Codificante/fisiología , Proteína bcl-X/metabolismo , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Animales , Caspasas/metabolismo , Línea Celular Tumoral , Proteínas de Unión al ADN/metabolismo , Humanos , Neoplasias Renales/genética , Neoplasias Renales/patología , Ratones , Ratones Desnudos , Datos de Secuencia Molecular , Regiones Promotoras Genéticas , Isoformas de Proteínas/análisis , Isoformas de Proteínas/genética , Empalme del ARN , ARN Largo no Codificante/análisis , ARN Largo no Codificante/biosíntesis , ARN Largo no Codificante/genética , Proteínas de Unión al ARN/metabolismo , Proteína bcl-X/análisis , Proteína bcl-X/genética
16.
PLoS Genet ; 9(8): e1003705, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23990798

RESUMEN

The down-regulation of the tumor-suppressor gene RASSF1A has been shown to increase cell proliferation in several tumors. RASSF1A expression is regulated through epigenetic events involving the polycomb repressive complex 2 (PRC2); however, the molecular mechanisms modulating the recruitment of this epigenetic modifier to the RASSF1 locus remain largely unknown. Here, we identify and characterize ANRASSF1, an endogenous unspliced long noncoding RNA (lncRNA) that is transcribed from the opposite strand on the RASSF1 gene locus in several cell lines and tissues and binds PRC2. ANRASSF1 is transcribed through RNA polymerase II and is 5'-capped and polyadenylated; it exhibits nuclear localization and has a shorter half-life compared with other lncRNAs that bind PRC2. ANRASSF1 endogenous expression is higher in breast and prostate tumor cell lines compared with non-tumor, and an opposite pattern is observed for RASSF1A. ANRASSF1 ectopic overexpression reduces RASSF1A abundance and increases the proliferation of HeLa cells, whereas ANRASSF1 silencing causes the opposite effects. These changes in ANRASSF1 levels do not affect the RASSF1C isoform abundance. ANRASSF1 overexpression causes a marked increase in both PRC2 occupancy and histone H3K27me3 repressive marks, specifically at the RASSF1A promoter region. No effect of ANRASSF1 overexpression was detected on PRC2 occupancy and histone H3K27me3 at the promoter regions of RASSF1C and the four other neighboring genes, including two well-characterized tumor suppressor genes. Additionally, we demonstrated that ANRASSF1 forms an RNA/DNA hybrid and recruits PRC2 to the RASSF1A promoter. Together, these results demonstrate a novel mechanism of epigenetic repression of the RASSF1A tumor suppressor gene involving antisense unspliced lncRNA, in which ANRASSF1 selectively represses the expression of the RASSF1 isoform overlapping the antisense transcript in a location-specific manner. In a broader perspective, our findings suggest that other non-characterized unspliced intronic lncRNAs transcribed in the human genome might contribute to a location-specific epigenetic modulation of genes.


Asunto(s)
Proliferación Celular , Complejo Represivo Polycomb 2/genética , ARN Largo no Codificante/metabolismo , Proteínas Supresoras de Tumor/genética , Islas de CpG , Metilación de ADN/genética , Regulación Neoplásica de la Expresión Génica , Silenciador del Gen , Células HeLa , Histonas/genética , Histonas/metabolismo , Humanos , Intrones/genética , Complejo Represivo Polycomb 2/metabolismo , Regiones Promotoras Genéticas , ARN Largo no Codificante/genética , Proteínas Supresoras de Tumor/metabolismo
17.
Parasitol Res ; 115(2): 817-28, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26547565

RESUMEN

Schistosoma mansoni and its vertebrate host have a complex and intimate connection in which several molecular stimuli are exchanged and affect both organisms. Human tumor necrosis factor alpha (hTNF-α), a pro-inflammatory cytokine, is known to induce large-scale gene expression changes in the parasite and to affect several parasite biological processes such as metabolism, egg laying, and worm development. Until now, the molecular mechanisms for TNF-α activity in worms are not completely understood. Here, we aimed at exploring the effect of hTNF-α on S. mansoni protein phosphorylation by 2D gel electrophoresis followed by a quantitative analysis of phosphoprotein staining and protein identification by mass spectrometry. We analyzed three biological replicates of adult male worms exposed to hTNF-α and successfully identified 32 protein spots with a statistically significant increase in phosphorylation upon in vitro exposure to hTNF-α. Among the differentially phosphorylated proteins, we found proteins involved in metabolism, such as glycolysis, galactose metabolism, urea cycle, and aldehyde metabolism, as well as proteins related to muscle contraction and to cytoskeleton remodeling. The most differentially phosphorylated protein (30-fold increase in phosphorylation) was 14-3-3, whose function is known to be modulated by phosphorylation, belonging to a signal transduction protein family that regulates a variety of processes in all eukaryotic cells. Further, 75% of the identified proteins are known in mammals to be related to TNF-α signaling, thus suggesting that TNF-α response may be conserved in the parasite. We propose that this work opens new perspectives to be explored in the study of the molecular crosstalk between host and pathogen.


Asunto(s)
Fosfoproteínas/metabolismo , Schistosoma mansoni/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Factor de Necrosis Tumoral alfa/farmacología , Animales , Metabolismo Energético/efectos de los fármacos , Ontología de Genes , Proteínas del Helminto/genética , Proteínas del Helminto/metabolismo , Interacciones Huésped-Parásitos , Humanos , Masculino , Espectrometría de Masas , Fosfoproteínas/genética , Fosforilación/efectos de los fármacos , Schistosoma mansoni/genética , Schistosoma mansoni/fisiología
18.
PLoS Pathog ; 9(6): e1003448, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23785292

RESUMEN

Schistosome parasites cause schistosomiasis, one of the most prevalent parasitemias worldwide affecting humans and animals. Constant pairing of schistosomes is essential for female sexual maturation and egg production, which causes pathogenesis. Female maturation involves signaling pathways controlling mitosis and differentiation within the gonads. In vitro studies had shown before that a Src-specific inhibitor, Herbimycin A (Herb A), and a TGFß receptor (TßR) inhibitor (TRIKI) have physiological effects such as suppressed mitoses and egg production in paired females. As one Herb A target, the gonad-specifically expressed Src kinase SmTK3 was identified. Here, we comparatively analyzed the transcriptome profiles of Herb A- and TRIKI-treated females identifying transcriptional targets of Src-kinase and TßRI pathways. After demonstrating that TRIKI inhibits the schistosome TGFßreceptor SmTßRI by kinase assays in Xenopus oocytes, couples were treated with Herb A, TRIKI, or both inhibitors simultaneously in vitro. RNA was isolated from females for microarray hybridizations and transcription analyses. The obtained data were evaluated by Gene Ontology (GO) and Ingenuity Pathway Analysis (IPA), but also by manual classification and intersection analyses. Finally, extensive qPCR experiments were done to verify differential transcription of candidate genes under inhibitor influence but also to functionally reinforce specific physiological effects. A number of genes found to be differentially regulated are associated with mitosis and differentiation. Among these were calcium-associated genes and eggshell-forming genes. In situ hybridization confirmed transcription of genes coding for the calcium sensor hippocalcin, the calcium transporter ORAI-1, and the calcium-binding protein calmodulin-4 in the reproductive system pointing to a role of calcium in parasite reproduction. Functional qPCR results confirmed an inhibitor-influenced, varying dependence of the transcriptional activities of Smp14, Smp48, fs800, a predicted eggshell precursor protein and SmTYR1. The results show that eggshell-formation is regulated by at least two pathways cooperatively operating in a balanced manner to control egg production.


Asunto(s)
Inhibidores Enzimáticos/farmacología , Proteínas del Helminto/metabolismo , Mitosis/efectos de los fármacos , Oocitos/metabolismo , Receptores de Factores de Crecimiento Transformadores beta/antagonistas & inhibidores , Rifabutina/análogos & derivados , Schistosoma/metabolismo , Transcriptoma/efectos de los fármacos , Familia-src Quinasas/antagonistas & inhibidores , Animales , Cricetinae , Femenino , Proteínas del Helminto/antagonistas & inhibidores , Proteínas del Helminto/genética , Mesocricetus , Mitosis/genética , Oocitos/citología , Receptores de Factores de Crecimiento Transformadores beta/genética , Receptores de Factores de Crecimiento Transformadores beta/metabolismo , Rifabutina/farmacología , Schistosoma/genética , Transcriptoma/genética , Xenopus laevis , Familia-src Quinasas/genética , Familia-src Quinasas/metabolismo
19.
RNA Biol ; 12(8): 877-92, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26151857

RESUMEN

Long noncoding RNAs (lncRNAs) that map to intragenic regions of the human genome with the same (intronic lncRNAs) or opposite orientation (antisense lncRNAs) relative to protein-coding mRNAs have been largely dismissed from biochemical and functional characterization due to the belief that they are mRNA precursors, byproducts of RNA splicing or simply transcriptional noise. In this work, we used a custom microarray to investigate aspects of the biogenesis, processing, stability, evolutionary conservation, and cellular localization of ∼ 6,000 intronic lncRNAs and ∼ 10,000 antisense lncRNAs. Most intronic (2,903 of 3,427, 85%) and antisense lncRNAs (4,945 of 5,214, 95%) expressed in HeLa cells showed evidence of 5' cap modification, compatible with their transcription by RNAP II. Antisense lncRNAs (median t1/2 = 3.9 h) were significantly (p < 0.0001) more stable than mRNAs (median t1/2 = 3.2 h), whereas intronic lncRNAs (median t1/2 = 2.1 h) comprised a more heterogeneous class that included both stable (t1/2 > 3 h) and unstable (t1/2 < 1 h) transcripts. Intragenic lncRNAs display evidence of evolutionary conservation, have little/no coding potential and were ubiquitously detected in the cytoplasm. Notably, a fraction of the intronic and antisense lncRNAs (13 and 15%, respectively) were expressed from loci at which the corresponding host mRNA was not detected. The abundances of a subset of intronic/antisense lncRNAs were correlated (r ≥ |0.8|) with those of genes encoding proteins involved in cell division and DNA replication. Taken together, the findings of this study contribute novel biochemical and genomic information regarding intronic and antisense lncRNAs, supporting the notion that these classes include independently transcribed RNAs with potentials for exerting regulatory functions in the cell.


Asunto(s)
Perfilación de la Expresión Génica/métodos , Genoma Humano/genética , Intrones/genética , ARN sin Sentido/genética , ARN Largo no Codificante/genética , Alfa-Amanitina/farmacología , Azacitidina/análogos & derivados , Azacitidina/farmacología , Línea Celular Tumoral , Metilasas de Modificación del ADN/antagonistas & inhibidores , Metilasas de Modificación del ADN/metabolismo , Dactinomicina/farmacología , Decitabina , Células HeLa , Humanos , Células MCF-7 , Inhibidores de la Síntesis del Ácido Nucleico , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , ARN Polimerasa II/antagonistas & inhibidores , ARN Polimerasa II/metabolismo , Estabilidad del ARN , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
20.
Biochim Biophys Acta ; 1832(2): 365-74, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23200924

RESUMEN

BACKGROUND: Several Rho GTPase-activating proteins (RhoGAPs) are implicated in tumor progression through their effects on Rho GTPase activity. ARHGAP21 is a RhoGAP with increased expression in head and neck squamous cell carcinoma and with a possible role in glioblastoma tumor progression, yet little is known about the function of ARHGAP21 in cancer cells. Here we studied the role of ARHGAP21 in two prostate adenocarcinoma cell lines, LNCaP and PC3, which respectively represent initial and advanced stages of prostate carcinogenesis. RESULTS: ARHGAP21 is located in the nucleus and cytoplasm of both cell lines and its depletion resulted in decreased proliferation and increased migration of PC3 cells but not LNCaP cells. In PC3 cells, ARHGAP21 presented GAP activity for RhoA and RhoC and induced changes in cell morphology. Moreover, its silencing altered the expression of genes involved in cell proliferation and cytoskeleton organization, as well as the endothelin-1 canonical pathway. CONCLUSIONS: Our results reveal new functions and signaling pathways regulated by ARHGAP21, and indicate that it could contribute to prostate cancer progression.


Asunto(s)
Adenocarcinoma/patología , Movimiento Celular , Proliferación Celular , Proteínas Activadoras de GTPasa/fisiología , Neoplasias de la Próstata/patología , Adenocarcinoma/metabolismo , Secuencia de Bases , Línea Celular Tumoral , Cartilla de ADN , Proteínas Activadoras de GTPasa/genética , Silenciador del Gen , Humanos , Etiquetado Corte-Fin in Situ , Masculino , Neoplasias de la Próstata/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
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