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1.
Acta Neuropathol Commun ; 12(1): 77, 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38762464

RESUMO

Glioblastoma (GBM) is the most common malignant brain tumor in adults, which remains incurable and often recurs rapidly after initial therapy. While large efforts have been dedicated to uncover genomic/transcriptomic alternations associated with the recurrence of GBMs, the evolutionary trajectories of matched pairs of primary and recurrent (P-R) GBMs remain largely elusive. It remains challenging to identify genes associated with time to relapse (TTR) and construct a stable and effective prognostic model for predicting TTR of primary GBM patients. By integrating RNA-sequencing and genomic data from multiple datasets of patient-matched longitudinal GBMs of isocitrate dehydrogenase wild-type (IDH-wt), here we examined the associations of TTR with heterogeneities between paired P-R GBMs in gene expression profiles, tumor mutation burden (TMB), and microenvironment. Our results revealed a positive correlation between TTR and transcriptomic/genomic differences between paired P-R GBMs, higher percentages of non-mesenchymal-to-mesenchymal transition and mesenchymal subtype for patients with a short TTR than for those with a long TTR, a high correlation between paired P-R GBMs in gene expression profiles and TMB, and a negative correlation between the fitting level of such a paired P-R GBM correlation and TTR. According to these observations, we identified 55 TTR-associated genes and thereby constructed a seven-gene (ZSCAN10, SIGLEC14, GHRHR, TBX15, TAS2R1, CDKL1, and CD101) prognostic model for predicting TTR of primary IDH-wt GBM patients using univariate/multivariate Cox regression analyses. The risk scores estimated by the model were significantly negatively correlated with TTR in the training set and two independent testing sets. The model also segregated IDH-wt GBM patients into two groups with significantly divergent progression-free survival outcomes and showed promising performance for predicting 1-, 2-, and 3-year progression-free survival rates in all training and testing sets. Our findings provide new insights into the molecular understanding of GBM progression at recurrence and potential targets for therapeutic treatments.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Isocitrato Desidrogenase , Recidiva Local de Neoplasia , Transcriptoma , Humanos , Glioblastoma/genética , Glioblastoma/patologia , Isocitrato Desidrogenase/genética , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Recidiva Local de Neoplasia/genética , Masculino , Feminino , Genômica/métodos , Mutação , Pessoa de Meia-Idade , Fatores de Tempo
2.
Nucleic Acids Res ; 52(D1): D115-D123, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-37823705

RESUMO

Circular RNAs (circRNAs) are RNA molecules with a continuous loop structure characterized by back-splice junctions (BSJs). While analyses of short-read RNA sequencing have identified millions of BSJ events, it is inherently challenging to determine exact full-length sequences and alternatively spliced (AS) isoforms of circRNAs. Recent advances in nanopore long-read sequencing with circRNA enrichment bring an unprecedented opportunity for investigating the issues. Here, we developed FL-circAS (https://cosbi.ee.ncku.edu.tw/FL-circAS/), which collected such long-read sequencing data of 20 cell lines/tissues and thereby identified 884 636 BSJs with 1 853 692 full-length circRNA isoforms in human and 115 173 BSJs with 135 617 full-length circRNA isoforms in mouse. FL-circAS also provides multiple circRNA features. For circRNA expression, FL-circAS calculates expression levels for each circRNA isoform, cell line/tissue specificity at both the BSJ and isoform levels, and AS entropy for each BSJ across samples. For circRNA biogenesis, FL-circAS identifies reverse complementary sequences and RNA binding protein (RBP) binding sites residing in flanking sequences of BSJs. For functional patterns, FL-circAS identifies potential microRNA/RBP binding sites and several types of evidence for circRNA translation on each full-length circRNA isoform. FL-circAS provides user-friendly interfaces for browsing, searching, analyzing, and downloading data, serving as the first resource for discovering full-length circRNAs at the isoform level.


Assuntos
Bases de Dados de Ácidos Nucleicos , RNA Circular , Animais , Humanos , Camundongos , Processamento Alternativo/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Sequenciamento por Nanoporos , RNA Circular/genética , Isoformas de RNA/genética
3.
Nat Methods ; 20(8): 1159-1169, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37443337

RESUMO

The detection of circular RNA molecules (circRNAs) is typically based on short-read RNA sequencing data processed using computational tools. Numerous such tools have been developed, but a systematic comparison with orthogonal validation is missing. Here, we set up a circRNA detection tool benchmarking study, in which 16 tools detected more than 315,000 unique circRNAs in three deeply sequenced human cell types. Next, 1,516 predicted circRNAs were validated using three orthogonal methods. Generally, tool-specific precision is high and similar (median of 98.8%, 96.3% and 95.5% for qPCR, RNase R and amplicon sequencing, respectively) whereas the sensitivity and number of predicted circRNAs (ranging from 1,372 to 58,032) are the most significant differentiators. Of note, precision values are lower when evaluating low-abundance circRNAs. We also show that the tools can be used complementarily to increase detection sensitivity. Finally, we offer recommendations for future circRNA detection and validation.


Assuntos
Benchmarking , RNA Circular , Humanos , RNA Circular/genética , RNA/genética , RNA/metabolismo , Análise de Sequência de RNA/métodos
4.
Nucleic Acids Res ; 51(15): 7777-7797, 2023 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-37497782

RESUMO

Trans-spliced RNAs (ts-RNAs) are a type of non-co-linear (NCL) transcripts that consist of exons in an order topologically inconsistent with the corresponding DNA template. Detecting ts-RNAs is often interfered by experimental artifacts, circular RNAs (circRNAs) and genetic rearrangements. Particularly, intragenic ts-RNAs, which are derived from separate precursor mRNA molecules of the same gene, are often mistaken for circRNAs through analyses of RNA-seq data. Here we developed a bioinformatics pipeline (NCLscan-hybrid), which integrated short and long RNA-seq reads to minimize false positives and proposed out-of-circle and rolling-circle long reads to distinguish between intragenic ts-RNAs and circRNAs. Combining NCLscan-hybrid screening and multiple experimental validation steps successfully confirmed that four NCL events, which were previously regarded as circRNAs in databases, originated from trans-splicing. CRISPR-based endogenous genome modification experiments further showed that flanking intronic complementary sequences can significantly contribute to ts-RNA formation, providing an efficient/specific method to deplete ts-RNAs. We also experimentally validated that one ts-RNA (ts-ARFGEF1) played an important role for p53-mediated apoptosis through affecting the PERK/eIF2a/ATF4/CHOP signaling pathway in breast cancer cells. This study thus described both bioinformatics procedures and experimental validation steps for rigorous characterization of ts-RNAs, expanding future studies for identification, biogenesis, and function of these important but understudied transcripts.


Assuntos
Análise de Sequência de RNA , Trans-Splicing , Genoma , Splicing de RNA , RNA Circular , Análise de Sequência de RNA/métodos
5.
Life Sci Alliance ; 6(5)2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36849251

RESUMO

Circular RNAs (circRNAs) are non-polyadenylated RNAs with a continuous loop structure characterized by a non-colinear back-splice junction (BSJ). Although millions of circRNA candidates have been identified, it remains a major challenge for determining circRNA reliability because of various types of false positives. Here, we systematically assess the impacts of numerous factors related to circRNA identification, conservation, biogenesis, and function on circRNA reliability by comparisons of circRNA expression from mock and the corresponding colinear/polyadenylated RNA-depleted datasets based on three different RNA treatment approaches. Eight important indicators of circRNA reliability are determined. The relative contribution to variability explained analyses reveal that the relative importance of these factors in affecting circRNA reliability in descending order is the conservation level of circRNA, full-length circular sequences, supporting BSJ read count, both BSJ donor and acceptor splice sites at the same colinear transcript isoforms, both BSJ donor and acceptor splice sites at the annotated exon boundaries, BSJs detected by multiple tools, supporting functional features, and both BSJ donor and acceptor splice sites undergoing alternative splicing. This study thus provides a useful guideline and an important resource for selecting high-confidence circRNAs for further investigations.


Assuntos
RNA Circular , RNA , RNA Circular/genética , Reprodutibilidade dos Testes , RNA/genética , Processamento Alternativo/genética , Éxons/genética
6.
Mol Psychiatry ; 27(11): 4695-4706, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35962193

RESUMO

Genetic risk variants and transcriptional expression changes in autism spectrum disorder (ASD) were widely investigated, but their causal relationship remains largely unknown. Circular RNAs (circRNAs) are abundant in brain and often serve as upstream regulators of mRNAs. By integrating RNA-sequencing with genotype data from autistic brains, we assessed expression quantitative trait loci of circRNAs (circQTLs) that cis-regulated expression of nearby circRNAs and trans-regulated expression of distant genes (trans-eGenes) simultaneously. We thus identified 3619 circQTLs that were also trans-eQTLs and constructed 19,804 circQTL-circRNA-trans-eGene regulatory axes. We conducted two different types of approaches, mediation and partial correlation tests (MPT), to determine the axes with mediation effects of circQTLs on trans-eGene expression through circRNA expression. We showed that the mediation effects of the circQTLs (trans-eQTLs) on circRNA expression were positively correlated with the magnitude of circRNA-trans-eGene correlation of expression profile. The positive correlation became more significant after adjustment for the circQTLs. Of the 19,804 axes, 8103 passed MPT. Meanwhile, we performed causal inference test (CIT) and identified 2070 circQTL-trans-eGene-ASD diagnosis propagation paths. We showed that the CIT-passing genes were significantly enriched for ASD risk genes, genes encoding postsynaptic density proteins, and other ASD-relevant genes, supporting the relevance of the CIT-passing genes to ASD pathophysiology. Integration of MPT- and CIT-passing axes further constructed 352 circQTL-circRNA-trans-eGene-ASD diagnosis propagation paths, wherein the circRNA-trans-eGene axes may act as causal mediators for the circQTL-ASD diagnosis associations. These analyses were also successfully applied to an independent dataset from schizophrenia brains. Collectively, this study provided the first framework for systematically investigating trans-genetic effects of circQTLs and inferring the corresponding causal relations in diseases. The identified circQTL-circRNA-trans-eGene regulatory interactions, particularly the internal modules that were previously implicated in the examined disorders, also provided a helpful dataset for further investigating causative biology and cryptic regulatory mechanisms underlying the neuropsychiatric diseases.


Assuntos
Transtorno do Espectro Autista , MicroRNAs , Humanos , RNA Circular/genética , Transtorno do Espectro Autista/genética , Locos de Características Quantitativas/genética , RNA Mensageiro/genética , Análise de Sequência de RNA , MicroRNAs/genética , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , RNA/genética
7.
Cells ; 10(11)2021 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-34831338

RESUMO

The developmental potential within pluripotent cells in the canonical model is restricted to embryonic tissues, whereas totipotent cells can differentiate into both embryonic and extraembryonic tissues. Currently, the ability to culture in vitro totipotent cells possessing molecular and functional features like those of an early embryo in vivo has been a challenge. Recently, it was reported that treatment with a single spliceosome inhibitor, pladienolide B (plaB), can successfully reprogram mouse pluripotent stem cells into totipotent blastomere-like cells (TBLCs) in vitro. The TBLCs exhibited totipotency transcriptionally and acquired expanded developmental potential with the ability to yield various embryonic and extraembryonic tissues that may be employed as novel mouse developmental cell models. However, it is disputed whether TBLCs are 'true' totipotent stem cells equivalent to in vivo two-cell stage embryos. To address this question, single-cell RNA sequencing was applied to TBLCs and cells from early mouse embryonic developmental stages and the data were integrated using canonical correlation analyses. Differential expression analyses were performed between TBLCs and multi-embryonic cell stages to identify differentially expressed genes. Remarkably, a subpopulation within the TBLCs population expressed a high level of the totipotent-related genes Zscan4s and displayed transcriptomic features similar to mouse two-cell stage embryonic cells. This study underscores the subtle differences between in vitro derived TBLCs and in vivo mouse early developmental cell stages at the single-cell transcriptomic level. Our study has identified a new experimental model for stem cell biology, namely 'cluster 3', as a subpopulation of TBLCs that can be molecularly defined as near totipotent cells.


Assuntos
Blastômeros/citologia , Embrião de Mamíferos/citologia , Células-Tronco Embrionárias Murinas/citologia , Análise de Célula Única , Células-Tronco Totipotentes/citologia , Transcriptoma/genética , Animais , Análise por Conglomerados , Regulação da Expressão Gênica , Ontologia Genética , Camundongos , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/metabolismo , Transdução de Sinais , Zigoto/metabolismo
8.
Res Nurs Health ; 44(4): 643-652, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34125441

RESUMO

This prospective study tested a model to depict associations between a number of individual characteristics and 6-month glycated hemoglobin (HbA1c) levels in adolescents with type 1 diabetes (T1D). Adolescents (N = 232) aged 10-19 years with T1D were recruited from a medical center in Taiwan. Demographic characteristics, emotional autonomy, problem-solving ability, self-efficacy at baseline, and self-management information three months after baseline were collected using a self-reported questionnaire. HbA1c levels 6 months after study commencement were obtained from medical records. Structural equation modeling was used to test the model. Higher baseline self-efficacy and self-management at 3 months were directly associated with lower 6-month HbA1c levels. Higher baseline problem-solving ability and self-efficacy were directly associated with higher 3-month self-management, and higher baseline problem-solving ability was directly associated with higher baseline self-efficacy. Higher baseline emotional autonomy was directly associated with lower 6-month HbA1c levels but indirectly associated with higher 6-month HbA1c levels through the mediation of lower problem-solving ability, self-efficacy, and 3-month self-management. Findings indicate that improving self-management is essential to improving subsequent glycemic control, which might be achieved by enhancing problem-solving ability and self-efficacy. Strengthening problem-solving ability could diminish the negative impact of emotional autonomy on subsequent glycemic control in adolescents with T1D.


Assuntos
Controle Glicêmico , Autonomia Pessoal , Resolução de Problemas , Autoeficácia , Autogestão , Adolescente , Diabetes Mellitus Tipo 1/psicologia , Feminino , Hemoglobinas Glicadas/análise , Humanos , Masculino , Estudos Prospectivos , Autorrelato , Inquéritos e Questionários , Taiwan
9.
J Pediatr Nurs ; 55: e263-e269, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32493633

RESUMO

BACKGROUND: High emotional autonomy has a negative association, whereas good problem-solving ability and parent-adolescent relationships have positive association with self-management in adolescents with type 1 diabetes (T1D). Exploring roles of these variables is crucial to design specific interventions to improve self-management in such afflicted adolescents. PURPOSE: To explore the roles of emotional autonomy, problem-solving ability and parent-adolescent relationships on self-management in adolescents with T1D. DESIGN AND METHODS: Cross-sectional design was used in this study. A total of 242 adolescents with T1D were recruited from an outpatient clinic of a medical center by convenience sampling in Taiwan. Self-reported questionnaires were used to collect personal characteristics, self-management, emotional autonomy, problem-solving ability, and parent-adolescent relationships. RESULTS: Hierarchical multiple regressions indicated that body mass index, problem-solving ability, father-adolescent relationship, and emotional autonomy were significant factors associated with self-management. The interactions of emotional autonomy with problem-solving ability and with parent-adolescents relationship were not significantly associated with self-management. The overall model explained 47.5% variance of self-management. CONCLUSIONS: High emotional autonomy was significantly associated with poor self-management. Problem-solving ability and father-adolescent relationships could not moderate, but were independently and significantly associated with self-management in adolescents with T1D. PRACTICE IMPLICATION: Healthcare providers should evaluate emotional autonomy earlier and provide more timely help to reduce any negative impact on self-management in adolescents with T1D. Improving problem-solving ability and encouraging fathers to develop optimal father-adolescents relationship might be promising strategies to enhance self-management in adolescents with T1D.


Assuntos
Diabetes Mellitus Tipo 1 , Autogestão , Adolescente , Estudos Transversais , Diabetes Mellitus Tipo 1/diagnóstico , Diabetes Mellitus Tipo 1/terapia , Humanos , Pais , Autocuidado , Taiwan
10.
Genome Res ; 30(3): 375-391, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32127416

RESUMO

Circular RNAs (circRNAs), a class of long noncoding RNAs, are known to be enriched in mammalian neural tissues. Although a wide range of dysregulation of gene expression in autism spectrum disorder (ASD) have been reported, the role of circRNAs in ASD remains largely unknown. Here, we performed genome-wide circRNA expression profiling in postmortem brains from individuals with ASD and controls and identified 60 circRNAs and three coregulated modules that were perturbed in ASD. By integrating circRNA, microRNA, and mRNA dysregulation data derived from the same cortex samples, we identified 8170 ASD-associated circRNA-microRNA-mRNA interactions. Putative targets of the axes were enriched for ASD risk genes and genes encoding inhibitory postsynaptic density (PSD) proteins, but not for genes implicated in monogenetic forms of other brain disorders or genes encoding excitatory PSD proteins. This reflects the previous observation that ASD-derived organoids show overproduction of inhibitory neurons. We further confirmed that some ASD risk genes (NLGN1, STAG1, HSD11B1, VIP, and UBA6) were regulated by an up-regulated circRNA (circARID1A) via sponging a down-regulated microRNA (miR-204-3p) in human neuronal cells. Particularly, alteration of NLGN1 expression is known to affect the dynamic processes of memory consolidation and strengthening. To the best of our knowledge, this is the first systems-level view of circRNA regulatory networks in ASD cortex samples. We provided a rich set of ASD-associated circRNA candidates and the corresponding circRNA-microRNA-mRNA axes, particularly those involving ASD risk genes. Our findings thus support a role for circRNA dysregulation and the corresponding circRNA-microRNA-mRNA axes in ASD pathophysiology.


Assuntos
Transtorno do Espectro Autista/genética , Regulação da Expressão Gênica , MicroRNAs/metabolismo , RNA Circular/metabolismo , RNA Mensageiro/metabolismo , Astrócitos/metabolismo , Transtorno do Espectro Autista/metabolismo , Encéfalo/metabolismo , Linhagem Celular , Genoma Humano , Humanos , Células-Tronco Neurais/metabolismo , Neurônios/metabolismo
12.
Acta Neuropathol Commun ; 7(1): 50, 2019 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-30922385

RESUMO

TAR DNA-binding protein (TDP-43) is a ubiquitously expressed nuclear protein, which participates in a number of cellular processes and has been identified as the major pathological factor in amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD). Here we constructed a conditional TDP-43 mouse with depletion of TDP-43 in the mouse forebrain and find that the mice exhibit a whole spectrum of age-dependent frontotemporal dementia-like behaviour abnormalities including perturbation of social behaviour, development of dementia-like behaviour, changes of activities of daily living, and memory loss at a later stage of life. These variations are accompanied with inflammation, neurodegeneration, and abnormal synaptic plasticity of the mouse CA1 neurons. Importantly, analysis of the cortical RNA transcripts of the conditional knockout mice at the pre-/post-symptomatic stages and the corresponding wild type mice reveals age-dependent alterations in the expression levels and RNA processing patterns of a set of genes closely associated with inflammation, social behaviour, synaptic plasticity, and neuron survival. This study not only supports the scenario that loss-of-function of TDP-43 in mice may recapitulate key behaviour features of the FTLD diseases, but also provides a list of TDP-43 target genes/transcript isoforms useful for future therapeutic research.


Assuntos
Proteínas de Ligação a DNA/deficiência , Demência Frontotemporal/metabolismo , Neurônios/metabolismo , Prosencéfalo/metabolismo , Transcriptoma/fisiologia , Fatores Etários , Animais , Proteínas de Ligação a DNA/genética , Demência Frontotemporal/genética , Demência Frontotemporal/patologia , Perfilação da Expressão Gênica/métodos , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Neurônios/patologia , Prosencéfalo/patologia
13.
BMC Bioinformatics ; 20(1): 3, 2019 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-30606103

RESUMO

BACKGROUND: Non-co-linear (NCL) transcripts consist of exonic sequences that are topologically inconsistent with the reference genome in an intragenic fashion (circular or intragenic trans-spliced RNAs) or in an intergenic fashion (fusion or intergenic trans-spliced RNAs). On the basis of RNA-seq data, numerous NCL event detectors have been developed and detected thousands of NCL events in diverse species. However, there are great discrepancies in the identification results among detectors, indicating a considerable proportion of false positives in the detected NCL events. Although several helpful guidelines for evaluating the performance of NCL event detectors have been provided, a systematic guideline for measurement of NCL events identified by existing tools has not been available. RESULTS: We develop a software, NCLcomparator, for systematically post-screening the intragenic or intergenic NCL events identified by various NCL detectors. NCLcomparator first examine whether the input NCL events are potentially false positives derived from ambiguous alignments (i.e., the NCL events have an alternative co-linear explanation or multiple matches against the reference genome). To evaluate the reliability of the identified NCL events, we define the NCL score (NCLscore) based on the variation in the number of supporting NCL junction reads identified by the tools examined. Of the input NCL events, we show that the ambiguous alignment-derived events have relatively lower NCLscore values than the other events, indicating that an NCL event with a higher NCLscore has a higher level of reliability. To help selecting highly expressed NCL events, NCLcomparator also provides a series of useful measurements such as the expression levels of the detected NCL events and their corresponding host genes and the junction usage of the co-linear splice junctions at both NCL donor and acceptor sites. CONCLUSION: NCLcomparator provides useful guidelines, with the input of identified NCL events from various detectors and the corresponding paired-end RNA-seq data only, to help users selecting potentially high-confidence NCL events for further functional investigation. The software thus helps to facilitate future studies into NCL events, shedding light on the fundamental biology of this important but understudied class of transcripts. NCLcomparator is freely accessible at https://github.com/TreesLab/NCLcomparator .


Assuntos
Fusão Gênica/genética , Genoma/genética , Splicing de RNA/genética , RNA/genética , Análise de Sequência de RNA/métodos
14.
Front Microbiol ; 9: 882, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29867797

RESUMO

In this study, we investigated gene expression changes in three bacterial strains (Escherichia coli C3000, Escherichia coli O157:H7 B6914, and Enterococcus faecalis ATCC 29212), commonly used as indicators of water quality and as control strains in clinical, food, and water microbiology laboratories. Bacterial transcriptome responses from pure cultures were monitored in microcosms containing water amended with manure-derived dissolved organic matter (DOM), previously exposed to simulated sunlight for 12 h. We used RNA sequencing (RNA-seq) and quantitative real-time reverse transcriptase (qRT-PCR) to compare differentially expressed temporal transcripts between bacteria incubated in microcosms containing sunlight irradiated and non-irradiated DOM, for up to 24 h. In addition, we used whole genome sequencing simultaneously with RNA-seq to identify single nucleotide variants (SNV) acquired in bacterial populations during incubation. These results indicate that E. coli and E. faecalis have different mechanisms for removal of reactive oxygen species (ROS) produced from irradiated DOM. They are also able to produce micromolar concentrations of H2O2 from non-irradiated DOM, that should be detrimental to other bacteria present in the environment. Notably, this study provides an assessment of the role of two conjugative plasmids carried by the E. faecalis and highlights the differences in the overall survival dynamics of environmentally-relevant bacteria in the presence of naturally-produced ROS.

15.
Nucleic Acids Res ; 46(7): 3671-3691, 2018 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-29385530

RESUMO

Transcriptionally non-co-linear (NCL) transcripts can originate from trans-splicing (trans-spliced RNA; 'tsRNA') or cis-backsplicing (circular RNA; 'circRNA'). While numerous circRNAs have been detected in various species, tsRNAs remain largely uninvestigated. Here, we utilize integrative transcriptome sequencing of poly(A)- and non-poly(A)-selected RNA-seq data from diverse human cell lines to distinguish between tsRNAs and circRNAs. We identified 24,498 NCL events and found that a considerable proportion (20-35%) of them arise from both tsRNAs and circRNAs, representing extensive alternative trans-splicing and cis-backsplicing in human cells. We show that sequence generalities of exon circularization are also observed in tsRNAs. Recapitulation of NCL RNAs further shows that inverted Alu repeats can simultaneously promote the formation of tsRNAs and circRNAs. However, tsRNAs and circRNAs exhibit quite different, or even opposite, expression patterns, in terms of correlation with the expression of their co-linear counterparts, expression breadth/abundance, transcript stability, and subcellular localization preference. These results indicate that tsRNAs and circRNAs may play different regulatory roles and analysis of NCL events should take the joint effects of different NCL-splicing types and joint effects of multiple NCL events into consideration. This study describes the first transcriptome-wide analysis of trans-splicing and cis-backsplicing, expanding our understanding of the complexity of the human transcriptome.


Assuntos
Processamento Alternativo/genética , RNA/genética , Trans-Splicing/genética , Transcriptoma/genética , Éxons/genética , Perfilação da Expressão Gênica , Humanos , Splicing de RNA/genética , RNA Circular
16.
Genome Biol Evol ; 10(2): 521-537, 2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-29294013

RESUMO

Adenosine-to-inosine (A-to-I) editing is widespread across the kingdom Metazoa. However, for the lack of comprehensive analysis in nonmodel animals, the evolutionary history of A-to-I editing remains largely unexplored. Here, we detect high-confidence editing sites using clustering and conservation strategies based on RNA sequencing data alone, without using single-nucleotide polymorphism information or genome sequencing data from the same sample. We thereby unveil the first evolutionary landscape of A-to-I editing maps across 20 metazoan species (from worm to human), providing unprecedented evidence on how the editing mechanism gradually expands its territory and increases its influence along the history of evolution. Our result revealed that highly clustered and conserved editing sites tended to have a higher editing level and a higher magnitude of the ADAR motif. The ratio of the frequencies of nonsynonymous editing to that of synonymous editing remarkably increased with increasing the conservation level of A-to-I editing. These results thus suggest potentially functional benefit of highly clustered and conserved editing sites. In addition, spatiotemporal dynamics analyses reveal a conserved enrichment of editing and ADAR expression in the central nervous system throughout more than 300 Myr of divergent evolution in complex animals and the comparability of editing patterns between invertebrates and between vertebrates during development. This study provides evolutionary and dynamic aspects of A-to-I editome across metazoan species, expanding this important but understudied class of nongenomically encoded events for comprehensive characterization.


Assuntos
Adenosina/genética , Inosina/genética , Edição de RNA , RNA/genética , Animais , Análise por Conglomerados , Evolução Molecular , Humanos , Análise de Sequência de RNA
17.
Sci Rep ; 7(1): 7038, 2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28765567

RESUMO

Genomic imprinting is an important epigenetic process that silences one of the parentally-inherited alleles of a gene and thereby exhibits allelic-specific expression (ASE). Detection of human imprinting events is hampered by the infeasibility of the reciprocal mating system in humans and the removal of ASE events arising from non-imprinting factors. Here, we describe a pipeline with the pattern of reciprocal allele descendants (RADs) through genotyping and transcriptome sequencing data across independent parent-offspring trios to discriminate between varied types of ASE (e.g., imprinting, genetic variation-dependent ASE, and random monoallelic expression (RME)). We show that the vast majority of ASE events are due to sequence-dependent genetic variant, which are evolutionarily conserved and may themselves play a cis-regulatory role. Particularly, 74% of non-RAD ASE events, even though they exhibit ASE biases toward the same parentally-inherited allele across different individuals, are derived from genetic variation but not imprinting. We further show that the RME effect may affect the effectiveness of the population-based method for detecting imprinting events and our pipeline can help to distinguish between these two ASE types. Taken together, this study provides a good indicator for categorization of different types of ASE, opening up this widespread and complex mechanism for comprehensive characterization.


Assuntos
Alelos , Saúde da Família , Perfilação da Expressão Gênica/métodos , Variação Genética , Impressão Genômica , Genótipo , Técnicas de Genotipagem/métodos , Humanos
18.
Carbon N Y ; 113: 346-360, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30147114

RESUMO

A major use of multi-walled carbon nanotubes (MWCNTs) is as functional fillers embedded in a solid matrix, such as plastics or coatings. Weathering and abrasion of the solid matrix during use can lead to environmental releases of the MWCNTs. Here we focus on a protocol to identify and quantify the primary release induced by weathering, and assess reproducibility, transferability, and sensitivity towards different materials and uses. We prepared 132 specimens of two polymer-MWCNT composites containing the same grade of MWCNTs used in earlier OECD hazard assessments but without UV stabilizer. We report on a pilot inter-laboratory comparison (ILC) with four labs (two US and two EU) aging by UV and rain, then shipping for analysis. Two labs (one US and one EU) conducted the release sampling and analysis by Transmission Electron Microscopy (TEM), Inductively Coupled Plasma- Mass Spectrometry (ICP-MS), UltravioleteVisible Spectroscopy (UVeVis), Analytical Ultracentrifugation (AUC), and Asymmetric Flow Field Flow Fractionation (AF4). We compare results between aging labs, between analysis labs and between materials. Surprisingly, we found quantitative agreement between analysis labs for TEM, ICP-MS, UVeVis; low variation between aging labs by all methods; and consistent rankings of release between TEM, ICP-MS, UVeVis, AUC. Significant disagreement was related primarily to differences in aging, but even these cases remained within a factor of two.

19.
Nurs Outlook ; 65(1): 68-76, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27640101

RESUMO

BACKGROUND: Adolescents with type 1 diabetes mellitus (T1DM) need to adapt physically and psychologically to the impact of diabetes. PURPOSE: The purpose of this study was to examine the pathways of emotional autonomy, depressive symptoms, and self-care behaviors to glycosylated hemoglobin (HbA1c) levels and quality of life (QoL) in adolescents with T1DM. METHODS: Cross-sectional design was used in this study. Self-reported questionnaires and medical records were used to collect data from 265 adolescents with T1DM by convenience sampling in Taiwan. DISCUSSION: Structural equation modeling indicated that self-care behaviors directly positively influenced life satisfaction QoL but negatively influenced HbA1c levels. Depressive symptoms directly negatively influenced self-care behaviors and life satisfaction QoL. Emotional autonomy directly negatively influenced self-care behaviors and life-satisfaction QoL but directly positively influenced depressive symptoms. CONCLUSION: Emotional autonomy seems to be a risk factor contributing to poor health adaptation. Health care providers need to help adolescents with T1DM to balance the pursuit of emotional autonomy and health adaptation.


Assuntos
Adaptação Fisiológica , Adaptação Psicológica , Comportamento do Adolescente/psicologia , Atitude Frente a Saúde , Diabetes Mellitus Tipo 1/psicologia , Qualidade de Vida/psicologia , Autocuidado/psicologia , Adolescente , Estudos Transversais , Feminino , Humanos , Masculino , Autonomia Pessoal , Inquéritos e Questionários , Taiwan
20.
Sci Rep ; 6: 27272, 2016 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-27255481

RESUMO

Genome-wide analysis has observed an excess of coincident single nucleotide polymorphisms (coSNPs) at human-chimpanzee orthologous positions, and suggested that this is due to cryptic variation in the mutation rate. While this phenomenon primarily corresponds with non-coding coSNPs, the situation in coding sequences remains unclear. Here we calculate the observed-to-expected ratio of coSNPs (coSNPO/E) to estimate the prevalence of human-chimpanzee coSNPs, and show that the excess of coSNPs is also present in coding regions. Intriguingly, coSNPO/E is much higher at zero-fold than at nonzero-fold degenerate sites; such a difference is due to an elevation of coSNPO/E at zero-fold degenerate sites, rather than a reduction at nonzero-fold degenerate ones. These trends are independent of chimpanzee subpopulation, population size, or sequencing techniques; and hold in broad generality across primates. We find that this discrepancy cannot fully explained by sequence contexts, shared ancestral polymorphisms, SNP density, and recombination rate, and that coSNPO/E in coding sequences is significantly influenced by purifying selection. We also show that selection and mutation rate affect coSNPO/E independently, and coSNPs tend to be less damaging and more correlated with human diseases than non-coSNPs. These suggest that coSNPs may represent a "signature" during primate protein evolution.


Assuntos
Pan troglodytes/genética , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA/métodos , Animais , Bases de Dados Genéticas , Evolução Molecular , Humanos , Taxa de Mutação , Seleção Genética
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