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1.
Stem Cell Reports ; 19(5): 689-709, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38701778

RESUMEN

Embryo size, specification, and homeostasis are regulated by a complex gene regulatory and signaling network. Here we used gene expression signatures of Wnt-activated mouse embryonic stem cell (mESC) clones to reverse engineer an mESC regulatory network. We identify NKX1-2 as a novel master regulator of preimplantation embryo development. We find that Nkx1-2 inhibition reduces nascent RNA synthesis, downregulates genes controlling ribosome biogenesis, RNA translation, and transport, and induces severe alteration of nucleolus structure, resulting in the exclusion of RNA polymerase I from nucleoli. In turn, NKX1-2 loss of function leads to chromosome missegregation in the 2- to 4-cell embryo stages, severe decrease in blastomere numbers, alterations of tight junctions (TJs), and impairment of microlumen coarsening. Overall, these changes impair the blastocoel expansion-collapse cycle and embryo cavitation, leading to altered lineage specification and developmental arrest.


Asunto(s)
Desarrollo Embrionario , Regulación del Desarrollo de la Expresión Génica , Proteínas de Homeodominio , Animales , Ratones , Desarrollo Embrionario/genética , Proteínas de Homeodominio/metabolismo , Proteínas de Homeodominio/genética , Células Madre Embrionarias de Ratones/metabolismo , Células Madre Embrionarias de Ratones/citología , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Blastocisto/metabolismo , Blastocisto/citología , Vía de Señalización Wnt , Proteínas Wnt/metabolismo , Uniones Estrechas/metabolismo , Nucléolo Celular/metabolismo
2.
Psychiatr Danub ; 35(Suppl 3): 17-23, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37994057

RESUMEN

People with autism and intellectual disabilities, much like individuals with typical development, share a fundamental right and aspiration to realise their own life projects. However, this natural pursuit is uniquely challenging for individuals with autism and intellectual disabilities due to their communication and adaptive hurdles. This growing need has prompted the development of a specific procedure for crafting life projects geared toward enhancing their quality of life. In the present work, we will describe the six key steps and the corresponding assessment, support, and verification tools essential for establishing and actualising the life project for individuals with disabilities, as conceptualised by the Italian Society of Neurodevelopmental Disorders (SIDIN). We will start by delineating diverse preference and value assessment procedures, showcasing an array of tools tailored to accommodate the distinct characteristics of adaptive and communicative functioning in individuals with disabilities. Following this, we will provide a succinct overview of support needs assessment tools. Subsequently, we will introduce the Ecological Life Balance, which serves as an integrative tool for harmonising various assessment systems. We will propose methods for defining existential goals that prioritise quality of life and suggest strategies for implementing support plans. Lastly, we will delve into the methodologies for monitoring and verifying outcomes in the final section.


Asunto(s)
Trastorno Autístico , Personas con Discapacidad , Discapacidad Intelectual , Humanos , Calidad de Vida , Comunicación
3.
Minerva Pediatr (Torino) ; 74(5): 579-585, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35166482

RESUMEN

INTRODUCTION: In recent years, the quick spread of Internet has brought many children and teenagers to be increasingly connected online without adult control. The use of Internet offers many opportunities, but at the same time it exposes young users to multiple risks. Among these, the consumption of sexually explicit internet material (SEIM) is one of the most relevant. The aim of the present study is to describe the epidemiology of this phenomenon regarding its prevalence and distribution among sexes and different age groups. EVIDENCE ACQUISITION: A literature search was performed on PubMed and ScienceDirect using the query "(pornography OR sexually explicit internet material) AND (adolescent OR child OR young)." Only papers published between 2013 and 2018 were included in the analysis. EVIDENCE SYNTHESIS: According to selected studies (N.=21), the prevalence of boys approaching SEIM ranges from 56% to 100%, whereas the percentage widely varies between 7.6% and 82% for girls. The first exposure to SEIM happens in a purely accidental way in over half of cases and at a mean age of 12 years for males and 14.5 years for females. The risk of exposure is doubled for smartphone and tablet owners. CONCLUSIONS: The spread of pornography and SEIM among minors seems to be epidemic and even pandemic. We need to consider its possible effects on the psychophysical welfare of the very young, influencing their growth and development. Therefore, the impact that pornography may have on the physical, psychological, and sexual health of younger people warrants further investigation.


Asunto(s)
Literatura Erótica , Conducta Sexual , Adolescente , Masculino , Adulto , Niño , Femenino , Humanos , Literatura Erótica/psicología , Conducta Sexual/psicología , Recolección de Datos
4.
Acta Biomed ; 92(6): e2021397, 2022 01 19.
Artículo en Inglés | MEDLINE | ID: mdl-35075080

RESUMEN

Background and aim Falls and fall-related injuries are a major public health issue which needs global attention due to its clinical and socioeconomic impact. Important risk factors for falls are polypharmacy and the assumption of so-called Fall Risk Increasing Drugs (FRIDs). Aims of our study were to investigate the associations between falls and the use of medications among inpatients by conducting a retrospective case-control study in a rehabilitation hospital in Northern Italy in 2018. Methods A Conditional Logistic Regression was performed to analyze the impact that 13 types of FRIDs individually and the number of administrated FRIDs had on the risk of falling. A second regression model was obtained adjusting the case-control matching for CIRS, Morse and Barthel scores. Results We identified 148 cases and 444 controls. 3 types of FRIDs were significantly correlated (p < 0,05) with an increased risk of falling: Antipsychotics, Antidepressants, Diuretics. Antidepressants were the only type of FRID significantly correlated (p=0,008) even in the model adjusted for CIRS, Morse and Barthel scores. The unadjusted model showed that the addition of one type of FRID to therapy was significantly associated with the fall event (p<0.05). Conclusion Assumption of drugs, in particular antidepressant and polypharmacy, can play a role in hospital falling. The fall risk assessment tools available, suffer from low specificity and sensitivity and do not assess these risk factors. A holistic approach with a multidimensional evaluation of the patient through screening tools, functional assessment tools and a full medical evaluation should be pursued to improve prediction.


Asunto(s)
Accidentes por Caídas , Preparaciones Farmacéuticas , Estudios de Casos y Controles , Hospitales , Humanos , Estudios Retrospectivos , Factores de Riesgo
5.
Minerva Pediatr (Torino) ; 74(3): 332-339, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-30761817

RESUMEN

INTRODUCTION: Nowadays adolescents and children are more and more exposed to sexually explicit internet material (SEIM), but most parents and healthcare professionals neglect this issue. The aim of the present study was to evaluate the impact of online pornography on minors' health with a specific focus on the effects produced on their behavioural, psychophysical and social development. EVIDENCE ACQUISITION: A literature search was performed on PubMed and ScienceDirect in March 2018 with the query "(pornography OR sexually explicit internet material) AND (adolescent OR child OR young) AND (impact OR behaviour OR health)." Results published between 2013 and 2018 were analysed and compared with previous evidence. EVIDENCE SYNTHESIS: According to selected studies (N.=19), an association between consumption of online pornography and several behavioral, psychophysical and social outcomes - earlier sexual debut, engaging with multiple and/or occasional partners, emulating risky sexual behaviors, assimilating distorted gender roles, dysfunctional body perception, aggressiveness, anxious or depressive symptoms, compulsive pornography use - is confirmed. CONCLUSIONS: The impact of online pornography on minors' health appears to be relevant. The issue can no longer be neglected and must be targeted by global and multidisciplinary interventions. Empowering parents, teachers and healthcare professionals by means of educational programs targeting this issue will allow them to assist minors in developing critical thinking skills about pornography, decreasing its use and obtaining an affective and sex education that is more suitable for their developmental needs.


Asunto(s)
Menores , Conducta Sexual , Adolescente , Niño , Literatura Erótica/psicología , Humanos , Internet , Educación Sexual , Conducta Sexual/psicología
7.
J Clin Med ; 10(21)2021 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-34768513

RESUMEN

Fibromyalgia (FM) has been explained as a result of gene-environment interactions. The present study aims to verify DNA methylation differences in eleven candidate genome regions previously associated to FM, evaluating DNA methylation patterns as potential disease biomarkers. DNA methylation was analyzed through bisulfite sequencing, comparing 42 FM women and their 42 healthy sisters. The associations between the level of methylation in these regions were further explored through a network analysis. Lastly, a logistic regression model investigated the regions potentially associated with FM, when controlling for sociodemographic variables and depressive symptoms. The analysis highlighted significant differences in the GCSAML region methylation between patients and controls. Moreover, seventeen single CpGs, belonging to other genes, were significantly different, however, only one cytosine related to GCSAML survived the correction for multiple comparisons. The network structure of methylation sites was different for each group; GRM2 methylation represented a central node only for FM patients. Logistic regression revealed that depressive symptoms and DNA methylation in the GRM2 region were significantly associated with FM risk. Our study encourages better exploration of GCSAML and GRM2 functions and their possible role in FM affecting immune, inflammatory response, and central sensitization of pain.

8.
Epidemiol Prev ; 45(4): 271-280, 2021.
Artículo en Italiano | MEDLINE | ID: mdl-34549569

RESUMEN

BACKGROUND: communicating breast cancer screening (BCS) limits and overdiagnosis implies providing complete and balanced information to allow informed decision-making. OBJECTIVES: to describe women's perceptions, preconceptions, and information preferences regarding the breast cancer screening (BCS) programme paper and web information materials of the Agency for Health Protection of the Metropolitan Area of Milan (Lombardy Region, Northern Italy). DESIGN: qualitative, descriptive study. SETTING AND PARTICIPANTS: participants' voluntary recruitment took place in the registration departments of three hospitals. Participants were purposively recruited based on sociodemographic characteristics of the target population of the programme (44 women aged 40-74 years, living in the Metropolitan Area of Milan). In each material type subgroup, different health literacy levels and age classes were included, until thematic saturation was reached. MAIN OUTCOME MEASURES: thematic analysis of qualitative data collected during think-aloud interviews. RESULTS: the thematic analysis identified 5 main themes: 1. validation of the information reported in the materials, according to the interviewees' personal experiences;2. information preferences of particular subgroups of women, which led to a tailored approach for the web materials;3. negative emotions elicited while receiving information regarding BCS limits, which guided the rewriting of certain definitions; 4. disproportioned risk perception, with greater weight attributed to the risk of false negative results than the risk of overdiagnosis; 5. organizational preferences regarding the type and frequency of the provided tests and the age limits of the programme. CONCLUSIONS: in the present sample of women living in the Metropolitan Area of Milan, knowledge and comprehension of overdiagnosis are scarce. The main reasons for distrust in the BCS programme rely on the preexisting beliefs regarding the most appropriate tests and age limits. These beliefs were established from previously received information, inconsistent with that officially provided by the programme.


Asunto(s)
Neoplasias de la Mama , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/epidemiología , Detección Precoz del Cáncer , Femenino , Humanos , Italia/epidemiología , Mamografía , Percepción
9.
Scand J Pain ; 21(2): 372-383, 2021 04 27.
Artículo en Inglés | MEDLINE | ID: mdl-34387961

RESUMEN

OBJECTIVES: The present pilot study aims to investigate DNA methylation changes of genes related to fibromyalgia (FM) development and its main comorbid symptoms, including sleep impairment, inflammation, depression and other psychiatric disorders. Epigenetic modifications might trigger or perpetuate complex interplay between pain transduction/transmission, central pain processing and experienced stressors in vulnerable individuals. METHODS: We conducted DNA methylation analysis by targeted bisulfite NGS sequencing testing differential methylation in 112 genomic regions from leukocytes of eight women with FM and their eight healthy sisters as controls. RESULTS: Tests for differentially methylated regions and cytosines brought focus on the GRM2 gene, encoding the metabotropic glutamate receptor2. The slightly increased DNA methylation observed in the GRM2 region of FM patients may confirm the involvement of the glutamate pathway in this pathological condition. Logistic regression highlighted the simultaneous association of methylation levels of depression and inflammation-related genes with FM. CONCLUSIONS: Altogether, the results evidence the glutamate pathway involvement in FM and support the idea that a combination of methylated and unmethylated genes could represent a risk factor to FM or its consequence, more than single genes. Further studies on the identified biomarkers could contribute to unravel the causative underlying FM mechanisms, giving reliable directions to research, improving the diagnosis and effective therapies.


Asunto(s)
Metilación de ADN , Fibromialgia , Receptores de Glutamato Metabotrópico/genética , Depresión/genética , Femenino , Fibromialgia/genética , Humanos , Inflamación/genética , Proyectos Piloto
10.
Mol Cell ; 81(15): 3065-3081.e12, 2021 08 05.
Artículo en Inglés | MEDLINE | ID: mdl-34297911

RESUMEN

The chromatin fiber folds into loops, but the mechanisms controlling loop extrusion are still poorly understood. Using super-resolution microscopy, we visualize that loops in intact nuclei are formed by a scaffold of cohesin complexes from which the DNA protrudes. RNA polymerase II decorates the top of the loops and is physically segregated from cohesin. Augmented looping upon increased loading of cohesin on chromosomes causes disruption of Lamin at the nuclear rim and chromatin blending, a homogeneous distribution of chromatin within the nucleus. Altering supercoiling via either transcription or topoisomerase inhibition counteracts chromatin blending, increases chromatin condensation, disrupts loop formation, and leads to altered cohesin distribution and mobility on chromatin. Overall, negative supercoiling generated by transcription is an important regulator of loop formation in vivo.


Asunto(s)
Proteínas de Ciclo Celular/metabolismo , Cromatina/química , Cromatina/genética , Proteínas Cromosómicas no Histona/metabolismo , Transcripción Genética/fisiología , Proteínas de Ciclo Celular/química , Proteínas de Ciclo Celular/genética , Línea Celular , Núcleo Celular/genética , Proteoglicanos Tipo Condroitín Sulfato/genética , Proteoglicanos Tipo Condroitín Sulfato/metabolismo , Cromatina/metabolismo , Proteínas Cromosómicas no Histona/química , Proteínas Cromosómicas no Histona/genética , ADN-Topoisomerasas de Tipo I/genética , ADN-Topoisomerasas de Tipo I/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Femenino , Humanos , Laminas/genética , Laminas/metabolismo , ARN Polimerasa II/metabolismo , Imagen Individual de Molécula/métodos , Cohesinas
11.
Cell Rep ; 33(10): 108474, 2020 12 08.
Artículo en Inglés | MEDLINE | ID: mdl-33296649

RESUMEN

Bi-species, fusion-mediated, somatic cell reprogramming allows precise, organism-specific tracking of unknown lineage drivers. The fusion of Tcf7l1-/- murine embryonic stem cells with EBV-transformed human B cell lymphocytes, leads to the generation of bi-species heterokaryons. Human mRNA transcript profiling at multiple time points permits the tracking of the reprogramming of B cell nuclei to a multipotent state. Interrogation of a human B cell regulatory network with gene expression signatures identifies 8 candidate master regulator proteins. Of these 8 candidates, ectopic expression of BAZ2B, from the bromodomain family, efficiently reprograms hematopoietic committed progenitors into a multipotent state and significantly enhances their long-term clonogenicity, stemness, and engraftment in immunocompromised mice. Unbiased systems biology approaches let us identify the early driving events of human B cell reprogramming.


Asunto(s)
Reprogramación Celular/genética , Células Madre Hematopoyéticas/metabolismo , Factores Generales de Transcripción/metabolismo , Animales , Linfocitos B/metabolismo , Diferenciación Celular/genética , Linaje de la Célula/genética , Reprogramación Celular/fisiología , Trasplante de Células Madre de Sangre del Cordón Umbilical/métodos , Femenino , Sangre Fetal/metabolismo , Trasplante de Células Madre Hematopoyéticas/métodos , Humanos , Masculino , Ratones , Ratones Endogámicos NOD , Células Madre Multipotentes/metabolismo , Factores de Transcripción/metabolismo , Factores Generales de Transcripción/genética , Factores Generales de Transcripción/fisiología
12.
Eur J Phys Rehabil Med ; 56(5): 537-546, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32667147

RESUMEN

BACKGROUND: Controlling inappropriateness of care is an essential issue, especially in rehabilitation medicine. In fact, admitting a patient to a rehabilitation hospital or unit is a complex decision also due to the absence of shared and objective admission criteria. AIM: The aim was to define clinical admission criteria and rules in rehabilitation medicine. DESIGN: Survey based on the application of the Delphi method on a sample of rehabilitation medicine experts. SETTING: Administration of electronic online questionnaires concerning appropriateness of admission to intensive rehabilitation. POPULATION: Volunteer sample of 53 experts with the following inclusion criteria: being members of the Italian Society of Physical and Rehabilitation Medicine, having practical experience in the research field, agreeing to the confidentiality of the information and being skilled in both rehabilitation and healthcare organization. METHODS: A three-round Delphi survey was conducted according to international guidelines. The two initial rounds consisted of an electronic online questionnaire while in the third one a report of the results was provided to the participants. The experts had to score their agreement with each item in the questionnaires, based on either a Likert scale or a dichotomous statement. Consensus between the experts was assessed. RESULTS: A total of 53 health professionals completed the Delphi survey. 19 out of 20 Italian regions were represented. The first round consisted of 8 multiple-choice questions. The second round was designed according to the suggestions provided by the panelists in the previous one and consisted of a twelve items questionnaire. At the end of the survey, seven criteria of appropriateness of admission to rehabilitation were identified and five rules defining an appropriate admission to a rehabilitation facility were elaborated. CONCLUSIONS: This study represents an attempt to create a worthwhile and reliable tool for a more conscious clinical practice in admission to rehabilitation, based on a set of shared criteria and rules. CLINICAL REHABILITATION IMPACT: To increase appropriateness of admission to rehabilitation. Improving appropriateness in healthcare delivery must be a primary goal in order to improve healthcare quality, save money and ensure system sustainability.


Asunto(s)
Admisión del Paciente/normas , Centros de Rehabilitación/normas , Técnica Delphi , Medicina Basada en la Evidencia , Femenino , Humanos , Italia , Masculino
13.
Ann Ist Super Sanita ; 56(2): 215-221, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32567571

RESUMEN

Supporting individuals with NDD is extremely demanding, with significant exposure to critical contexts and events, and painful ongoing experiences. Stress and burnout condition is a main concern with growing interest in research, despite the lack of consensus on theoretical explanatory models and modification standards.The paper provides an up-to-date review of risk factors and involved processes, and presents evidence-based procedures and protocols to implement effective preventive actions addressing both organizational and individual factors. The aim is to offer a global understanding of the subject and offer examples of practical plans to increase the impact on the quality of life of clients and staff members.


Asunto(s)
Personal de Salud/psicología , Trastornos del Neurodesarrollo/rehabilitación , Estrés Psicológico/psicología , Adulto , Trastorno del Espectro Autista/rehabilitación , Agotamiento Profesional/epidemiología , Agotamiento Profesional/psicología , Niño , Humanos , Satisfacción en el Trabajo , Calidad de Vida , Estrés Psicológico/epidemiología
14.
Ann Ist Super Sanita ; 56(2): 230-240, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32567573

RESUMEN

For some years, the term "project of life" has become widely used in the field of neurodevelopmental disorders, and, at the same time, it has begun to make its way in many social and health planning documents. However, beyond its relatively widespread use, this term does not yet possess an adequate and shared frame of the main underlying decision-making processes. In particular, there is a need to identify the crucial questions for orienting the choice of goals within the adolescent transition, which represents the complex hinge between childhood and adulthood. Moreover, adulthood, which is often completely devoid of culturally and socially shared references, is still critical precisely because of the lack of future direction prompts usually represented by the stages of development. In this case, the themes of quality of life functioning as a guiding compass appear pertinent and much more relevant. The present contribution is, therefore, an attempt to present, in a unitary manner, the decision-making processes and questions at the basis of a construct of "project of life" shared within the scientific and associative communities.


Asunto(s)
Trastornos del Neurodesarrollo/psicología , Trastornos del Neurodesarrollo/rehabilitación , Planificación de Atención al Paciente/organización & administración , Calidad de Vida , Adulto , Niño , Humanos
16.
Int J Mol Sci ; 20(13)2019 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-31284509

RESUMEN

Alu retroelements, whose retrotransposition requires prior transcription by RNA polymerase III to generate Alu RNAs, represent the most numerous non-coding RNA (ncRNA) gene family in the human genome. Alu transcription is generally kept to extremely low levels by tight epigenetic silencing, but it has been reported to increase under different types of cell perturbation, such as viral infection and cancer. Alu RNAs, being able to act as gene expression modulators, may be directly involved in the mechanisms determining cellular behavior in such perturbed states. To directly address the regulatory potential of Alu RNAs, we generated IMR90 fibroblasts and HeLa cell lines stably overexpressing two slightly different Alu RNAs, and analyzed genome-wide the expression changes of protein-coding genes through RNA-sequencing. Among the genes that were upregulated or downregulated in response to Alu overexpression in IMR90, but not in HeLa cells, we found a highly significant enrichment of pathways involved in cell cycle progression and mitotic entry. Accordingly, Alu overexpression was found to promote transition from G1 to S phase, as revealed by flow cytometry. Therefore, increased Alu RNA may contribute to sustained cell proliferation, which is an important factor of cancer development and progression.


Asunto(s)
Elementos Alu/genética , Proteínas de Ciclo Celular/genética , Ciclo Celular/genética , Fibroblastos/metabolismo , Regulación de la Expresión Génica , ARN/genética , Secuencia de Bases , Proteínas de Ciclo Celular/metabolismo , Sitios Genéticos , Genoma Humano , Células HeLa , Humanos , ARN/metabolismo
17.
Emerg Top Life Sci ; 3(4): 343-355, 2019 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-33523206

RESUMEN

In the last two decades, we have witnessed an impressive crescendo of non-coding RNA studies, due to both the development of high-throughput RNA-sequencing strategies and an ever-increasing awareness of the involvement of newly discovered ncRNA classes in complex regulatory networks. Together with excitement for the possibility to explore previously unknown layers of gene regulation, these advancements led to the realization of the need for shared criteria of data collection and analysis and for novel integrative perspectives and tools aimed at making biological sense of very large bodies of molecular information. In the last few years, efforts to respond to this need have been devoted mainly to the regulatory interactions involving ncRNAs as direct or indirect regulators of protein-coding mRNAs. Such efforts resulted in the development of new computational tools, allowing the exploitation of the information spread in numerous different ncRNA data sets to interpret transcriptome changes under physiological and pathological cell responses. While experimental validation remains essential to identify key RNA regulatory interactions, the integration of ncRNA big data, in combination with systematic literature mining, is proving to be invaluable in identifying potential new players, biomarkers and therapeutic targets in cancer and other diseases.

18.
Noncoding RNA ; 3(1)2017 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-29657287

RESUMEN

Short Interspersed Element (SINE) retrotransposons are one of the most abundant DNA repeat elements in the human genome. They have been found to impact the expression of protein-coding genes, but the possible roles in cell physiology of their noncoding RNAs, generated by RNA polymerase (Pol) III, are just starting to be elucidated. For this reason, Short Interspersed Element (SINE) expression profiling is becoming mandatory to obtain a comprehensive picture of their regulatory roles. However, their repeated nature and frequent location within Pol II-transcribed genes represent a serious obstacle to the identification and quantification of genuine, Pol III-derived SINE transcripts at single-locus resolution on a genomic scale. Among the recent Next Generation Sequencing technologies, only RNA sequencing (RNA-Seq) holds the potential to solve these issues, even though both technical and biological matters need to be taken into account. A bioinformatic pipeline has been recently set up that, by exploiting RNA-seq features and knowledge of SINE transcription mechanisms, allows for easy identification and profiling of transcriptionally active genomic loci which are a source of genuine Pol III SINE transcripts.

19.
DNA Res ; 24(1): 59-69, 2017 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-28028040

RESUMEN

With more than 500,000 copies, mammalian-wide interspersed repeats (MIRs), a sub-group of SINEs, represent ∼2.5% of the human genome and one of the most numerous family of potential targets for the RNA polymerase (Pol) III transcription machinery. Since MIR elements ceased to amplify ∼130 myr ago, previous studies primarily focused on their genomic impact, while the issue of their expression has not been extensively addressed. We applied a dedicated bioinformatic pipeline to ENCODE RNA-Seq datasets of seven human cell lines and, for the first time, we were able to define the Pol III-driven MIR transcriptome at single-locus resolution. While the majority of Pol III-transcribed MIR elements are cell-specific, we discovered a small set of ubiquitously transcribed MIRs mapping within Pol II-transcribed genes in antisense orientation that could influence the expression of the overlapping gene. We also identified novel Pol III-transcribed ncRNAs, deriving from transcription of annotated MIR fragments flanked by unique MIR-unrelated sequences, and confirmed the role of Pol III-specific internal promoter elements in MIR transcription. Besides demonstrating widespread transcription at these retrotranspositionally inactive elements in human cells, the ability to profile MIR expression at single-locus resolution will facilitate their study in different cell types and states including pathological alterations.


Asunto(s)
Secuencias Repetitivas Esparcidas , Biología Computacional , Perfilación de la Expresión Génica , Células HeLa , Humanos , Plásmidos , Retroelementos , Análisis de Secuencia de ARN , Transcripción Genética
20.
Nucleic Acids Res ; 43(2): 817-35, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25550429

RESUMEN

Of the ∼ 1.3 million Alu elements in the human genome, only a tiny number are estimated to be active in transcription by RNA polymerase (Pol) III. Tracing the individual loci from which Alu transcripts originate is complicated by their highly repetitive nature. By exploiting RNA-Seq data sets and unique Alu DNA sequences, we devised a bioinformatic pipeline allowing us to identify Pol III-dependent transcripts of individual Alu elements. When applied to ENCODE transcriptomes of seven human cell lines, this search strategy identified ∼ 1300 Alu loci corresponding to detectable transcripts, with ∼ 120 of them expressed in at least three cell lines. In vitro transcription of selected Alus did not reflect their in vivo expression properties, and required the native 5'-flanking region in addition to internal promoter. We also identified a cluster of expressed AluYa5-derived transcription units, juxtaposed to snaR genes on chromosome 19, formed by a promoter-containing left monomer fused to an Alu-unrelated downstream moiety. Autonomous Pol III transcription was also revealed for Alus nested within Pol II-transcribed genes. The ability to investigate Alu transcriptomes at single-locus resolution will facilitate both the identification of novel biologically relevant Alu RNAs and the assessment of Alu expression alteration under pathological conditions.


Asunto(s)
Elementos Alu , ARN Polimerasa III/metabolismo , Transcripción Genética , Perfilación de la Expresión Génica , Silenciador del Gen , Sitios Genéticos , Genómica/métodos , Humanos , Análisis de Secuencia de ARN , Factores de Transcripción/metabolismo , Transcriptoma
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