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1.
J Digit Imaging ; 35(5): 1373-1381, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35419665

RESUMEN

This study aimed to establish and validate a novel evaluation method using digital tomosynthesis to quantify bone formation in the gap after opening wedge high tibial osteotomy (OW-HTO). We retrospectively analyzed bone formation in the gap in 22 patients who underwent OW-HTO using digital tomosynthesis at 1, 2, 3, 6, 9, and 12 months postoperatively. Bone formation was semi-quantitatively assessed using the modified van Hemert's score and density measurements on digital tomosynthesis images. The gap filling value (GFV) was calculated as the ratio of the intensities of the opening gap and the tibial shaft. In addition, the relationship between the modified van Hemert's score and GFV was evaluated. The reproducibility of GFV had an interclass correlation coefficient (ICC [1,2]) of 0.958 for intraobserver reliability and an ICC (2,1) of 0.975 for interobserver reliability. The GFV increased in a time-dependent manner and was moderately correlated with the modified van Hemert's score (r = 0.630, p < 0.001). The GFV plateaued at 6 months postoperatively. In addition, the GFV was higher in patients with a modified van Hemert's score of 2 than in patients with a modified van Hemert's score of 3 (p = 0.008). The GFVs obtained using digital tomosynthesis can be used to assess postoperative bone formation in the opening gap after OW-HTO with high accuracy and reproducibility.


Asunto(s)
Osteoartritis de la Rodilla , Humanos , Reproducibilidad de los Resultados , Osteoartritis de la Rodilla/diagnóstico por imagen , Osteoartritis de la Rodilla/cirugía , Articulación de la Rodilla , Estudios Retrospectivos , Osteogénesis , Osteotomía/métodos , Tibia/diagnóstico por imagen , Tibia/cirugía
2.
Biochem Biophys Res Commun ; 534: 186-192, 2021 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-33309273

RESUMEN

Platelet-derived growth factor receptor alpha (PDGFRα) is a dominant marker of mesodermal mesenchymal cells in mice. Previous studies demonstrated that PDGFRα-positive (PDGFRα+) mesodermal cells develop not only into mesenchymal cells but also into a subset of total hematopoietic cells (HCs) in the limited period during mouse embryogenesis. However, the precise characteristics of the PDGFRα lineage positive (PDGFRα Lin+) HCs in adult mouse hematopoiesis are largely unknown. In this study, we systematically evaluated the characteristics of PDGFRα Lin+ HCs in the bone marrow and peripheral blood using PDGFRα-CRE; ROSAtdTomato mice. Flow cytometry analysis revealed that PDGFRα Lin+ HCs accounted for approximately 20% of total HCs in both the bone marrow and peripheral blood in adult mice. Compositions of myeloid and lymphoid subpopulations among CD45+ mononuclear cells were almost identical in both PDGFRα Lin+ and PDGFRα Lin- cells. Single-cell RNA-sequencing analysis also demonstrated that the transcriptomic signatures of the PDGFRα Lin+ HCs in the peripheral blood largely overlapped with those of the PDGFRα Lin- HCs, suggesting equivalent functions of the PDGFRα Lin+ and PDGFRα Lin- HCs. Although pathophysiological activities of the PDGFRα Lin + HCs were not evaluated, our data clearly demonstrate a significant role of the PDGFRα Lin + HCs in physiological hematopoiesis in adult mice.


Asunto(s)
Hematopoyesis , Células Madre Hematopoyéticas/fisiología , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/metabolismo , Animales , Linaje de la Célula , Femenino , Hematopoyesis/genética , Células Madre Hematopoyéticas/metabolismo , Masculino , Mesodermo/citología , Ratones , RNA-Seq , Análisis de la Célula Individual
3.
BMC Genomics ; 20(1): 614, 2019 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-31357933

RESUMEN

BACKGROUND: Deciphering the 3D structure of the genome is essential for elucidating the regulatory mechanisms of gene expression in detail. Existing methods, such as chromosome conformation capture (3C) and Hi-C have enabled the identification of novel aspects of chromatin structure. Further identification of protein-centric chromatin conformation is enabled by coupling the Hi-C procedure with a conventional chromatin immunoprecipitation assay. However, these methods are time-consuming and require independent methods for validation. RESULTS: To simultaneously identify protein-centric chromatin conformation and target protein localization, we have developed Cut-C, a method that combines antibody-mediated cleavage by tethered nuclease with chromosome conformation capture to identify chromatin interactions mediated by a protein of interest. Applying Cut-C to H3K4me3, a histone modification enriched at active gene promoters, we have successfully identified chromatin loops mediated by H3K4me3 along with the genome-wide distribution of H3K4me3. Cut-C also identified chromatin loops mediated by CTCF, validating the general applicability of the method. CONCLUSIONS: Cut-C identifies protein-centric chromatin conformations along with the genome-wide distribution of target proteins using simple procedures. The simplified protocol will improve the efficiency of analysing chromatin conformation using precious materials, such as clinical samples.


Asunto(s)
Cromatina/química , Cromatina/metabolismo , Desoxirribonucleasas/metabolismo , Genómica , Células HEK293 , Histonas/química , Histonas/metabolismo , Humanos , Lisina/metabolismo , Conformación Proteica
4.
J Immunol ; 194(6): 2673-82, 2015 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-25681338

RESUMEN

Cyclodextrins are commonly used as a safe excipient to enhance the solubility and bioavailability of hydrophobic pharmaceutical agents. Their efficacies and mechanisms as drug-delivery systems have been investigated for decades, but their immunological properties have not been examined. In this study, we reprofiled hydroxypropyl-ß-cyclodextrin (HP-ß-CD) as a vaccine adjuvant and found that it acts as a potent and unique adjuvant. HP-ß-CD triggered the innate immune response at the injection site, was trapped by MARCO(+) macrophages, increased Ag uptake by dendritic cells, and facilitated the generation of T follicular helper cells in the draining lymph nodes. It significantly enhanced Ag-specific Th2 and IgG Ab responses as potently as did the conventional adjuvant, aluminum salt (alum), whereas its ability to induce Ag-specific IgE was less than that of alum. At the injection site, HP-ß-CD induced the temporary release of host dsDNA, a damage-associated molecular pattern. DNase-treated mice, MyD88-deficient mice, and TBK1-deficient mice showed significantly reduced Ab responses after immunization with this adjuvant. Finally, we demonstrated that HP-ß-CD-adjuvanted influenza hemagglutinin split vaccine protected against a lethal challenge with a clinically isolated pandemic H1N1 influenza virus, and the adjuvant effect of HP-ß-CD was demonstrated in cynomolgus macaques. Our results suggest that HP-ß-CD acts as a potent MyD88- and TBK1-dependent T follicular helper cell adjuvant and is readily applicable to various vaccines.


Asunto(s)
Antígenos/inmunología , Inflamación/inmunología , Linfocitos T Colaboradores-Inductores/inmunología , Células Th2/inmunología , beta-Ciclodextrinas/inmunología , 2-Hidroxipropil-beta-Ciclodextrina , Adyuvantes Inmunológicos/administración & dosificación , Animales , Formación de Anticuerpos/efectos de los fármacos , Formación de Anticuerpos/genética , Formación de Anticuerpos/inmunología , Antígenos/administración & dosificación , Interacciones Huésped-Patógeno/efectos de los fármacos , Interacciones Huésped-Patógeno/inmunología , Inflamación/genética , Subtipo H1N1 del Virus de la Influenza A/inmunología , Subtipo H1N1 del Virus de la Influenza A/fisiología , Vacunas contra la Influenza/administración & dosificación , Vacunas contra la Influenza/inmunología , Ganglios Linfáticos/efectos de los fármacos , Ganglios Linfáticos/inmunología , Ganglios Linfáticos/metabolismo , Macaca fascicularis , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados , Microscopía de Fluorescencia por Excitación Multifotónica , Análisis de Secuencia por Matrices de Oligonucleótidos , Infecciones por Orthomyxoviridae/inmunología , Infecciones por Orthomyxoviridae/prevención & control , Infecciones por Orthomyxoviridae/virología , Bazo/efectos de los fármacos , Bazo/inmunología , Bazo/metabolismo , Linfocitos T Colaboradores-Inductores/efectos de los fármacos , Linfocitos T Colaboradores-Inductores/metabolismo , Células Th2/efectos de los fármacos , Células Th2/metabolismo , Transcriptoma/efectos de los fármacos , Transcriptoma/inmunología , beta-Ciclodextrinas/administración & dosificación
5.
Bioinformatics ; 30(18): 2559-67, 2014 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-24876376

RESUMEN

MOTIVATION: Chromosome rearrangement events are triggered by atypical breaking and rejoining of DNA molecules, which are observed in many cancer-related diseases. The detection of rearrangement is typically done by using short reads generated by next-generation sequencing (NGS) and combining the reads with knowledge of a reference genome. Because structural variations and genomes differ from one person to another, intermediate comparison via a reference genome may lead to loss of information. RESULTS: In this article, we propose a reference-free method for detecting clusters of breakpoints from the chromosomal rearrangements. This is done by directly comparing a set of NGS normal reads with another set that may be rearranged. Our method SlideSort-BPR (breakpoint reads) is based on a fast algorithm for all-against-all comparisons of short reads and theoretical analyses of the number of neighboring reads. When applied to a dataset with a sequencing depth of 100×, it finds ∼ 88% of the breakpoints correctly with no false-positive reads. Moreover, evaluation on a real prostate cancer dataset shows that the proposed method predicts more fusion transcripts correctly than previous approaches, and yet produces fewer false-positive reads. To our knowledge, this is the first method to detect breakpoint reads without using a reference genome. AVAILABILITY AND IMPLEMENTATION: The source code of SlideSort-BPR can be freely downloaded from https://code.google.com/p/slidesort-bpr/.


Asunto(s)
Algoritmos , Puntos de Rotura del Cromosoma , Genómica/métodos , Secuenciación de Nucleótidos de Alto Rendimiento , Translocación Genética/genética , Humanos , Masculino , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología , Análisis de Secuencia de ADN , Programas Informáticos
6.
BMC Plant Biol ; 14: 291, 2014 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-25404140

RESUMEN

BACKGROUND: Salt stress is a major challenge for growth and development of plants. The mangrove tree Avicennia officinalis has evolved salt tolerance mechanisms such as salt secretion through specialized glands on its leaves. Although a number of structural studies on salt glands have been done, the molecular mechanism of salt secretion is not clearly understood. Also, studies to identify salt gland-specific genes in mangroves have been scarce. RESULTS: By subtractive hybridization (SH) of cDNA from salt gland-rich cell layers (tester) with mesophyll tissues as the driver, several Expressed Sequence Tags (ESTs) were identified. The major classes of ESTs identified include those known to be involved in regulating metabolic processes (37%), stress response (17%), transcription (17%), signal transduction (17%) and transport functions (12%). A visual interactive map generated based on predicted functional gene interactions of the identified ESTs suggested altered activities of hydrolase, transmembrane transport and kinases. Quantitative Real-Time PCR (qRT-PCR) was carried out to validate the expression specificity of the ESTs identified by SH. A Dehydrin gene was chosen for further experimental analysis, because it is significantly highly expressed in salt gland cells, and dehydrins are known to be involved in stress remediation in other plants. Full-length Avicennia officinalis Dehydrin1 (AoDHN1) cDNA was obtained by Rapid Amplification of cDNA Ends. Phylogenetic analysis and further characterization of this gene suggested that AoDHN1 belongs to group II Late Embryogenesis Abundant proteins. qRT-PCR analysis of Avicennia showed up-regulation of AoDHN1 in response to salt and drought treatments. Furthermore, some functional insights were obtained by growing E. coli cells expressing AoDHN1. Growth of E. coli cells expressing AoDHN1 was significantly higher than that of the control cells without AoDHN1 under salinity and drought stresses, suggesting that the mangrove dehydrin protein helps to mitigate the abiotic stresses. CONCLUSIONS: Thirty-four ESTs were identified to be enriched in salt gland-rich tissues of A. officinalis leaves. qRT-PCR analysis showed that 10 of these were specifically enriched in the salt gland-rich tissues. Our data suggest that one of the selected genes, namely, AoDHN1 plays an important role to mitigate salt and drought stress responses.


Asunto(s)
Avicennia/genética , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genética , Cloruro de Sodio/metabolismo , Secuencia de Aminoácidos , Animales , Avicennia/efectos de los fármacos , Avicennia/fisiología , Secuencia de Bases , ADN Complementario/química , ADN Complementario/genética , Sequías , Escherichia coli/genética , Escherichia coli/metabolismo , Etiquetas de Secuencia Expresada , Redes Reguladoras de Genes , Datos de Secuencia Molecular , Filogenia , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/genética , Hojas de la Planta/fisiología , Proteínas de Plantas/metabolismo , Tolerancia a la Sal , Análisis de Secuencia de ADN , Cloruro de Sodio/farmacología , Regulación hacia Arriba
7.
Nucleic Acids Res ; 40(Database issue): D1089-92, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22139942

RESUMEN

The field of gene expression analysis continues to benefit from next-generation sequencing generated data, which enables transcripts to be measured with unmatched accuracy and resolution. But the high-throughput reads from these technologies also contain many errors, which can compromise the ability to accurately detect and quantify rare transcripts. Fortunately, techniques exist to ameliorate the affects of sequencer error. We present RecountDB, a secondary database derived from primary data in NCBI's short read archive. RecountDB holds sequence counts from RNA-seq and 5' capped transcription start site experiments, corrected and mapped to the relevant genome. Via a searchable and browseable interface users can obtain corrected data in formats useful for transcriptomic analysis. The database is currently populated with 2265 entries from 45 organisms and continuously growing. RecountDB is publicly available at: http://recountdb.cbrc.jp.


Asunto(s)
Bases de Datos de Ácidos Nucleicos , Perfilación de la Expresión Génica , Análisis de Secuencia de ARN , Mapeo Cromosómico , Alineación de Secuencia , Sitio de Iniciación de la Transcripción
8.
Bioinformatics ; 27(22): 3085-92, 2011 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-21976422

RESUMEN

MOTIVATION: Recent studies have revealed the importance of considering quality scores of reads generated by next-generation sequence (NGS) platforms in various downstream analyses. It is also known that probabilistic alignments based on marginal probabilities (e.g. aligned-column and/or gap probabilities) provide more accurate alignment than conventional maximum score-based alignment. There exists, however, no study about probabilistic alignment that considers quality scores explicitly, although the method is expected to be useful in SNP/indel callers and bisulfite mapping, because accurate estimation of aligned columns or gaps is important in those analyses. RESULTS: In this study, we propose methods of probabilistic alignment that consider quality scores of (one of) the sequences as well as a usual score matrix. The method is based on posterior decoding techniques in which various marginal probabilities are computed from a probabilistic model of alignments with quality scores, and can arbitrarily trade-off sensitivity and positive predictive value (PPV) of prediction (aligned columns and gaps). The method is directly applicable to read mapping (alignment) toward accurate detection of SNPs and indels. Several computational experiments indicated that probabilistic alignments can estimate aligned columns and gaps accurately, compared with other mapping algorithms e.g. SHRiMP2, Stampy, BWA and Novoalign. The study also suggested that our approach yields favorable precision for SNP/indel calling.


Asunto(s)
Mutación INDEL , Modelos Estadísticos , Polimorfismo de Nucleótido Simple , Alineación de Secuencia/métodos , Análisis de Secuencia de ADN , Algoritmos , Humanos
9.
Cell Mol Gastroenterol Hepatol ; 12(2): 547-566, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33862275

RESUMEN

BACKGROUND & AIMS: Proper resolution of inflammation is essential to maintaining homeostasis, which is important as a dysregulated inflammatory response has adverse consequences, even being regarded as a hallmark of cancer. However, our picture of dynamic changes during inflammation remains far from comprehensive. METHODS: Here we used single-cell transcriptomics to elucidate changes in distinct cell types and their interactions in a mouse model of chemically induced colitis. RESULTS: Our analysis highlights the stromal cell population of the colon functions as a hub with dynamically changing roles over time. Importantly, we found that Serpina3n, a serine protease inhibitor, is specifically expressed in stromal cell clusters as inflammation resolves, interacting with a potential target, elastase. Indeed, genetic ablation of the Serpina3n gene delays resolution of induced inflammation. Furthermore, systemic Serpina3n administration promoted the resolution of inflammation, ameliorating colitis symptoms. CONCLUSIONS: This study provides a comprehensive, single-cell understanding of cell-cell interactions during colorectal inflammation and reveals a potential therapeutic target that leverages inflammation resolution.


Asunto(s)
Proteínas de Fase Aguda/metabolismo , Colitis/genética , Colitis/patología , Inflamación/genética , Inflamación/patología , Serpinas/metabolismo , Análisis de la Célula Individual , Transcriptoma/genética , Animales , Comunicación Celular , Colon/patología , Sulfato de Dextran , Modelos Animales de Enfermedad , Predisposición Genética a la Enfermedad , Enfermedades Inflamatorias del Intestino/genética , Enfermedades Inflamatorias del Intestino/patología , Ratones Endogámicos C57BL , Fenotipo , RNA-Seq , Factores de Riesgo , Células del Estroma/metabolismo
10.
BMC Plant Biol ; 10: 16, 2010 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-20100339

RESUMEN

BACKGROUND: The transcriptional regulatory network involved in low temperature response leading to acclimation has been established in Arabidopsis. In japonica rice, which can only withstand transient exposure to milder cold stress (10 degrees C), an oxidative-mediated network has been proposed to play a key role in configuring early responses and short-term defenses. The components, hierarchical organization and physiological consequences of this network were further dissected by a systems-level approach. RESULTS: Regulatory clusters responding directly to oxidative signals were prominent during the initial 6 to 12 hours at 10 degrees C. Early events mirrored a typical oxidative response based on striking similarities of the transcriptome to disease, elicitor and wounding induced processes. Targets of oxidative-mediated mechanisms are likely regulated by several classes of bZIP factors acting on as1/ocs/TGA-like element enriched clusters, ERF factors acting on GCC-box/JAre-like element enriched clusters and R2R3-MYB factors acting on MYB2-like element enriched clusters.Temporal induction of several H2O2-induced bZIP, ERF and MYB genes coincided with the transient H2O2 spikes within the initial 6 to 12 hours. Oxidative-independent responses involve DREB/CBF, RAP2 and RAV1 factors acting on DRE/CRT/rav1-like enriched clusters and bZIP factors acting on ABRE-like enriched clusters. Oxidative-mediated clusters were activated earlier than ABA-mediated clusters. CONCLUSION: Genome-wide, physiological and whole-plant level analyses established a holistic view of chilling stress response mechanism of japonica rice. Early response regulatory network triggered by oxidative signals is critical for prolonged survival under sub-optimal temperature. Integration of stress and developmental responses leads to modulated growth and vigor maintenance contributing to a delay of plastic injuries.


Asunto(s)
Frío , Redes Reguladoras de Genes , Oryza/genética , Estrés Oxidativo , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Peróxido de Hidrógeno/metabolismo , Análisis de Secuencia por Matrices de Oligonucleótidos , Oryza/crecimiento & desarrollo , Oryza/metabolismo , Oxidación-Reducción , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regiones Promotoras Genéticas , ARN de Planta/genética , Transducción de Señal , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
11.
Plant Cell Environ ; 33(12): 2209-30, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20807373

RESUMEN

The R2R3-type OsMyb4 transcription factor of rice has been shown to play a role in the regulation of osmotic adjustment in heterologous overexpression studies. However, the exact composition and organization of its underlying transcriptional network has not been established to be a robust tool for stress tolerance enhancement by regulon engineering. OsMyb4 network was dissected based on commonalities between the global chilling stress transcriptome and the transcriptome configured by OsMyb4 overexpression. OsMyb4 controls a hierarchical network comprised of several regulatory sub-clusters associated with cellular defense and rescue, metabolism and development. It regulates target genes either directly or indirectly through intermediary MYB, ERF, bZIP, NAC, ARF and CCAAT-HAP transcription factors. Regulatory sub-clusters have different combinations of MYB-like, GCC-box-like, ERD1-box-like, ABRE-like, G-box-like, as1/ocs/TGA-like, AuxRE-like, gibberellic acid response element (GARE)-like and JAre-like cis-elements. Cold-dependent network activity enhanced cellular antioxidant capacity through radical scavenging mechanisms and increased activities of phenylpropanoid and isoprenoid metabolic processes involving various abscisic acid (ABA), jasmonic acid (JA), salicylic acid (SA), ethylene and reactive oxygen species (ROS) responsive genes. OsMyb4 network is independent of drought response element binding protein/C-repeat binding factor (DREB/CBF) and its sub-regulons operate with possible co-regulators including nuclear factor-Y. Because of its upstream position in the network hierarchy, OsMyb4 functions quantitatively and pleiotrophically. Supra-optimal expression causes misexpression of alternative targets with costly trade-offs to panicle development.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Redes Reguladoras de Genes , Oryza/metabolismo , Estrés Fisiológico , Factores de Transcripción/metabolismo , Frío , Copas de Floración/crecimiento & desarrollo , Oryza/genética , Oryza/crecimiento & desarrollo , Fenotipo , Plantas Modificadas Genéticamente/crecimiento & desarrollo , Plantas Modificadas Genéticamente/metabolismo
12.
Bioinformatics ; 24(20): 2288-95, 2008 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-18697768

RESUMEN

MOTIVATION: Locating transcription factor binding sites (motifs) is a key step in understanding gene regulation. Based on Tompa's benchmark study, the performance of current de novo motif finders is far from satisfactory (with sensitivity

Asunto(s)
Biología Computacional/métodos , Elementos Reguladores de la Transcripción , Factores de Transcripción/metabolismo , Animales , Secuencia de Bases , Sitios de Unión , Humanos , Datos de Secuencia Molecular , Estructura Terciaria de Proteína , Programas Informáticos , Factores de Transcripción/química
13.
Genome Inform ; 23(1): 189-201, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20180274

RESUMEN

Next generation sequencing technologies enable rapid, large-scale production of sequence data sets. Unfortunately these technologies also have a non-neglible sequencing error rate, which biases their outputs by introducing false reads and reducing the quantity of the real reads. Although methods developed for SAGE data can reduce these false counts to a considerable degree, until now they have not been implemented in a scalable way. Recently, a program named FREC has been developed to address this problem for next generation sequencing data. In this paper, we introduce RECOUNT, our implementation of an Expectation Maximization algorithm for tag count correction and compare it to FREC. Using both the reference genome and simulated data, we find that RECOUNT performs as well or better than FREC, while using much less memory (e.g. 5GB vs. 75GB). Furthermore, we report the first analysis of tag count correction with real data in the context of gene expression analysis. Our results show that tag count correction not only increases the number of mappable tags, but can make a real difference in the biological interpretation of next generation sequencing data. RECOUNT is an open-source C++ program available at http://seq.cbrc.jp/recount.


Asunto(s)
Análisis de Secuencia de ADN/métodos , Genoma , Modelos Estadísticos , Probabilidad
14.
Bioinformatics ; 23(12): 1476-85, 2007 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-17483509

RESUMEN

MOTIVATION: Identification of motifs is one of the critical stages in studying the regulatory interactions of genes. Motifs can have complicated patterns. In particular, spaced motifs, an important class of motifs, consist of several short segments separated by spacers of different lengths. Locating spaced motifs is not trivial. Existing motif-finding algorithms are either designed for monad motifs (short contiguous patterns with some mismatches) or have assumptions on the spacer lengths or can only handle at most two segments. An effective motif finder for generic spaced motifs is highly desirable. RESULTS: This article proposes a novel approach for identifying spaced motifs with any number of spacers of different lengths. We introduce the notion of submotifs to capture the segments in the spaced motif and formulate the motif-finding problem as a frequent submotif mining problem. We provide an algorithm called SPACE to solve the problem. Based on experiments on real biological datasets, synthetic datasets and the motif assessment benchmarks by Tompa et al., we show that our algorithm performs better than existing tools for spaced motifs with improvements in both sensitivity and specificity and for monads, SPACE performs as good as other tools. AVAILABILITY: The source code is available upon request from the authors.


Asunto(s)
Secuencias de Aminoácidos , Biología Computacional/métodos , Reconocimiento de Normas Patrones Automatizadas , Algoritmos , Secuencia de Bases , Sitios de Unión , Modelos Estadísticos , Unión Proteica , Estructura Terciaria de Proteína , Alineación de Secuencia , Análisis de Secuencia de ADN , Factores de Transcripción/genética
15.
Sci Rep ; 8(1): 17765, 2018 12 10.
Artículo en Inglés | MEDLINE | ID: mdl-30531792

RESUMEN

Mesenchymal stem cells (MSCs), which can differentiate into tri-lineage (osteoblast, adipocyte, and chondrocyte) and suppress inflammation, are promising tools for regenerative medicine. MSCs are phenotypically diverse based on their tissue origins. However, the mechanisms underlying cell-type-specific gene expression patterns are not fully understood due to the lack of suitable strategy to identify the diversity. In this study, we investigated gene expression programs and chromatin accessibilities of MSCs by whole-transcriptome RNA-seq analysis and an assay for transposase-accessible chromatin using sequencing (ATAC-seq). We isolated MSCs from four tissues (femoral and vertebral bone marrow, adipose tissue, and lung) and analysed their molecular signatures. RNA-seq identified the expression of MSC markers and both RNA-seq and ATAC-seq successfully clustered the MSCs based on their tissue origins. Interestingly, clustering based on tissue origin was more accurate with chromatin accessibility signatures than with transcriptome profiles. Furthermore, we identified transcription factors potentially involved in establishing cell-type specific chromatin structures. Thus, epigenome analysis is useful to analyse MSC identity and can be utilized to characterize these cells for clinical use.


Asunto(s)
Cromatina/genética , Cromatina/metabolismo , Células Madre Mesenquimatosas/metabolismo , Adipocitos/metabolismo , Adipocitos/fisiología , Tejido Adiposo/metabolismo , Tejido Adiposo/fisiología , Animales , Biomarcadores/metabolismo , Células de la Médula Ósea/metabolismo , Células de la Médula Ósea/fisiología , Análisis por Conglomerados , Fémur/metabolismo , Fémur/fisiología , Expresión Génica/genética , Expresión Génica/fisiología , Perfilación de la Expresión Génica/métodos , Pulmón/metabolismo , Pulmón/fisiología , Ratones , Ratones Endogámicos C57BL , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Transcriptoma/genética , Transcriptoma/fisiología
16.
Adv Appl Bioinform Chem ; 10: 1-9, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28203094

RESUMEN

PURPOSE: Evidence suggests that circulating serum microRNAs (miRNAs) might preferentially target immune-related mRNAs. If this were the case, we hypothesized that immune-related mRNAs would have more predicted serum miRNA binding sites than other mRNAs and, reciprocally, that serum miRNAs would have more immune-related mRNA targets than non-serum miRNAs. MATERIALS AND METHODS: We developed a consensus target predictor using the random forest framework and calculated the number of predicted miRNA-mRNA interactions in various subsets of miRNAs (serum, non-serum) and mRNAs (immune related, nonimmune related). RESULTS: Immune-related mRNAs were predicted to be targeted by serum miRNA more than other mRNAs. Moreover, serum miRNAs were predicted to target many more immune-related mRNA targets than non-serum miRNAs; however, these two biases in immune-related mRNAs and serum miRNAs appear to be completely independent. CONCLUSION: Immune-related mRNAs have more miRNA binding sites in general, not just for serum miRNAs; likewise, serum miRNAs target many more mRNAs than non-serum miRNAs overall, regardless of whether they are immune related or not. Nevertheless, these two independent phenomena result in a significantly larger number of predicted serum miRNA-immune mRNA interactions than would be expected by chance.

17.
Sci Rep ; 7(1): 10031, 2017 08 30.
Artículo en Inglés | MEDLINE | ID: mdl-28855698

RESUMEN

Salinity affects growth and development of plants, but mangroves exhibit exceptional salt tolerance. With direct exposure to salinity, mangrove roots possess specific adaptations to tolerate salt stress. Therefore, studying the early effects of salt on mangrove roots can help us better understand the tolerance mechanisms. Using two-month-old greenhouse-grown seedlings of the mangrove tree Avicennia officinalis subjected to NaCl treatment, we profiled gene expression changes in the roots by RNA-sequencing. Of the 6547 genes that were differentially regulated in response to salt treatment, 1404 and 5213 genes were significantly up- and down-regulated, respectively. By comparative genomics, 93 key salt tolerance-related genes were identified of which 47 were up-regulated. Upon placing all the differentially expressed genes (DEG) in known signaling pathways, it was evident that most of the DEGs involved in ethylene and auxin signaling were up-regulated while those involved in ABA signaling were down-regulated. These results imply that ABA-independent signaling pathways also play a major role in salt tolerance of A. officinalis. Further, ethylene response factors (ERFs) were abundantly expressed upon salt treatment and the Arabidopsis mutant aterf115, a homolog of AoERF114 is characterized. Overall, our results would help in understanding the possible molecular mechanism underlying salt tolerance in plants.


Asunto(s)
Avicennia/genética , Regulación de la Expresión Génica de las Plantas , Estrés Salino , Transcriptoma , Avicennia/metabolismo , Ácidos Indolacéticos/metabolismo , Raíces de Plantas/genética , Raíces de Plantas/metabolismo , Transducción de Señal
18.
Sci Rep ; 7(1): 12847, 2017 10 09.
Artículo en Inglés | MEDLINE | ID: mdl-28993694

RESUMEN

Evaluation of immune responses in individual immune cell types is important for the development of new medicines. Here, we propose a computational method designated ICEPOP (Immune CEll POPulation) to estimate individual immune cell type responses from bulk tissue and organ samples. The relative gene responses are scored for each cell type by using the data from differentially expressed genes derived from control- vs drug-treated sample pairs, and the data from public databases including ImmGen and IRIS, which contain gene expression profiles of a variety of immune cells. By ICEPOP, we analysed cell responses induced by vaccine-adjuvants in the mouse spleen, and extended the analyses to human peripheral blood mononuclear cells and gut biopsy samples focusing on human papilloma virus vaccination and inflammatory bowel disease treatment with Infliximab. In both mouse and human datasets, our method reliably quantified the responding immune cell types and provided insightful information, demonstrating that our method is useful to evaluate immune responses from bulk sample-derived gene expression data. ICEPOP is available as an interactive web site ( https://vdynamics.shinyapps.io/icepop/ ) and Python package ( https://github.com/ewijaya/icepop ).


Asunto(s)
Leucocitos Mononucleares/metabolismo , Especificidad de Órganos/genética , Especificidad de Órganos/inmunología , Transcriptoma , Animales , Biopsia , Contaminación de ADN , Bases de Datos Genéticas , Tracto Gastrointestinal/patología , Papillomavirus Humano 16/inmunología , Humanos , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Infliximab/uso terapéutico , Ratones , Programas Informáticos , Bazo/metabolismo , Virión/inmunología
19.
EBioMedicine ; 15: 127-136, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27919753

RESUMEN

Advax, a delta inulin-derived microparticle, has been developed as an adjuvant for several vaccines. However, its immunological characteristics and potential mechanism of action are yet to be elucidated. Here, we show that Advax behaves as a type-2 adjuvant when combined with influenza split vaccine, a T helper (Th)2-type antigen, but behaves as a type-1 adjuvant when combined with influenza inactivated whole virion (WV), a Th1-type antigen. In addition, an adjuvant effect was not observed when Advax-adjuvanted WV vaccine was used to immunize toll-like receptor (TLR) 7 knockout mice which are unable to respond to RNA contained in WV antigen. Similarly, no adjuvant effect was seen when Advax was combined with endotoxin-free ovalbumin, a neutral Th0-type antigen. An adjuvant effect was also not seen in tumor necrosis factor (TNF)-α knockout mice, and the adjuvant effect required the presences of dendritic cells (DCs) and phagocytic macrophages. Therefore, unlike other adjuvants, Advax potentiates the intrinsic or in-built adjuvant property of co-administered antigens. Hence, Advax is a unique class of adjuvant which can potentiate the intrinsic adjuvant feature of the vaccine antigens through a yet to be determined mechanism.


Asunto(s)
Adyuvantes Inmunológicos/administración & dosificación , Inulina/análogos & derivados , Vacunas/administración & dosificación , Vacunas/inmunología , Animales , Antígenos/inmunología , Biomarcadores , Citocinas/biosíntesis , Células Dendríticas/inmunología , Células Dendríticas/metabolismo , Femenino , Inmunización , Inulina/administración & dosificación , Liposomas , Activación de Linfocitos , Macrófagos/inmunología , Macrófagos/metabolismo , Masculino , Ratones , Ratones Noqueados , Modelos Animales , Fagocitosis/inmunología , Transducción de Señal , Células Th2/inmunología , Células Th2/metabolismo
20.
Rice (N Y) ; 9(1): 51, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27681580

RESUMEN

BACKGROUND: Rice is the only crop that germinates and elongates the coleoptile under complete submergence. It has been shown that alcohol dehydrogenase 1 (ADH1)-deficient mutant of rice with reduced alcohol dehydrogenase activity (rad) and reduced ATP level, is viable with much reduced coleoptile elongation under such condition. To understand the altered transcriptional regulatory mechanism of this mutant, we aimed to establish possible relationships between gene expression and cis-regulatory information content. FINDINGS: We performed promoter analysis of the publicly available differentially expressed genes in ADH1 mutant. Our results revealed that a crosstalk between a number of key transcription factors (TFs) and different phytohormones altered transcriptional regulation leading to the survival of the mutant. Amongst the key TFs identified, we suggest potential involvement of MYB, bZIP, ARF and ERF as transcriptional activators and WRKY, ABI4 and MYC as transcriptional repressors of coleoptile elongation to maintain metabolite levels for the cell viability. Out of the repressors, WRKY TF is most likely playing a major role in the alteration of the physiological implications associated with the cell survival. CONCLUSIONS: Overall, our analysis provides a possible transcriptional regulatory mechanism underlying the survival of the rad mutant under complete submergence in an energy crisis condition and develops hypotheses for further experimental validation.

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