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1.
Plant Physiol ; 159(1): 391-402, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22452854

RESUMEN

Plants modify harmful substances through an inducible detoxification system. In Arabidopsis (Arabidopsis thaliana), chemical induction of the cytochrome P450 gene CYP81D11 and other genes linked to the detoxification program depends on class II TGA transcription factors. CYP81D11 expression is also induced by the phytohormone jasmonic acid (JA) through the established pathway requiring the JA receptor CORONATINE INSENSITIVE1 (COI1) and the JA-regulated transcription factor MYC2. Here, we report that the xenobiotic- and the JA-dependent signal cascades have become interdependent at the CYP81D11 promoter. On the one hand, MYC2 can only activate the expression of CYP81D11 when both the MYC2- and the TGA-binding sites are present in the promoter. On the other hand, the xenobiotic-regulated class II TGA transcription factors can only mediate maximal promoter activity if TGA and MYC2 binding motifs, MYC2, and the JA-isoleucine biosynthesis enzymes DDE2/AOS and JAR1 are functional. Since JA levels and degradation of JAZ1, a repressor of the JA response, are not affected by reactive chemicals, we hypothesize that basal JA signaling amplifies the response to chemical stress. Remarkably, stress-induced expression levels were 3-fold lower in coi1 than in the JA biosynthesis mutant dde2-2, [corrected] revealing that COI1 can contribute to the activation of the promoter in the absence of JA. Moreover, we show that deletion of the MYC2 binding motifs abolishes the JA responsiveness of the promoter but not the responsiveness to COI1. These findings suggest that yet unknown cis-element(s) can mediate COI1-dependent transcriptional activation in the absence of JA.


Asunto(s)
Arabidopsis/genética , Ciclopentanos/metabolismo , Sistema Enzimático del Citocromo P-450/genética , Oxilipinas/metabolismo , Regiones Promotoras Genéticas , Transducción de Señal/efectos de los fármacos , Xenobióticos/farmacología , Secuencias de Aminoácidos , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/genética , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/metabolismo , Benzoxazoles/farmacología , Ciclopentanos/farmacología , Sistema Enzimático del Citocromo P-450/metabolismo , Regulación de la Expresión Génica de las Plantas , Nucleotidiltransferasas/genética , Nucleotidiltransferasas/metabolismo , Oxilipinas/farmacología , Plásmidos/genética , Plásmidos/metabolismo , Secuencias Reguladoras de Ácidos Nucleicos , Activación Transcripcional , Transformación Genética , Ácidos Triyodobenzoicos/farmacología
2.
Eur J Hum Genet ; 25(2): 176-182, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27848944

RESUMEN

We report our results of 1000 diagnostic WES cases based on 2819 sequenced samples from 54 countries with a wide phenotypic spectrum. Clinical information given by the requesting physicians was translated to HPO terms. WES processes were performed according to standardized settings. We identified the underlying pathogenic or likely pathogenic variants in 307 families (30.7%). In further 253 families (25.3%) a variant of unknown significance, possibly explaining the clinical symptoms of the index patient was identified. WES enabled timely diagnosing of genetic diseases, validation of causality of specific genetic disorders of PTPN23, KCTD3, SCN3A, PPOX, FRMPD4, and SCN1B, and setting dual diagnoses by detecting two causative variants in distinct genes in the same patient. We observed a better diagnostic yield in consanguineous families, in severe and in syndromic phenotypes. Our results suggest that WES has a better yield in patients that present with several symptoms, rather than an isolated abnormality. We also validate the clinical benefit of WES as an effective diagnostic tool, particularly in nonspecific or heterogeneous phenotypes. We recommend WES as a first-line diagnostic in all cases without a clear differential diagnosis, to facilitate personal medical care.


Asunto(s)
Exoma , Pruebas Genéticas/métodos , Técnicas de Genotipaje/métodos , Análisis de Secuencia de ADN/métodos , Adolescente , Adulto , Niño , Preescolar , Femenino , Flavoproteínas/genética , Pruebas Genéticas/normas , Técnicas de Genotipaje/normas , Humanos , Lactante , Recién Nacido , Péptidos y Proteínas de Señalización Intracelular/genética , Masculino , Persona de Mediana Edad , Proteínas Mitocondriales/genética , Canal de Sodio Activado por Voltaje NAV1.3/genética , Núcleo Familiar , Fenotipo , Canales de Potasio/genética , Proteínas Tirosina Fosfatasas no Receptoras/genética , Protoporfirinógeno-Oxidasa/genética , Análisis de Secuencia de ADN/normas , Canales de Sodio/genética , Subunidad beta-1 de Canal de Sodio Activado por Voltaje/genética
3.
J Mol Diagn ; 17(2): 162-70, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25556971

RESUMEN

Genetic testing for hereditary breast and/or ovarian cancer mostly relies on laborious molecular tools that use Sanger sequencing to scan for mutations in the BRCA1 and BRCA2 genes. We explored a more efficient genetic screening strategy based on next-generation sequencing of the BRCA1 and BRCA2 genes in 210 hereditary breast and/or ovarian cancer patients. We first validated this approach in a cohort of 115 samples with previously known BRCA1 and BRCA2 mutations and polymorphisms. Genomic DNA was amplified using the Ion AmpliSeq BRCA1 and BRCA2 panel. The DNA Libraries were pooled, barcoded, and sequenced using an Ion Torrent Personal Genome Machine sequencer. The combination of different robust bioinformatics tools allowed detection of all previously known pathogenic mutations and polymorphisms in the 115 samples, without detecting spurious pathogenic calls. We then used the same assay in a discovery cohort of 95 uncharacterized hereditary breast and/or ovarian cancer patients for BRCA1 and BRCA2. In addition, we describe the allelic frequencies across 210 hereditary breast and/or ovarian cancer patients of 74 unique definitely and likely pathogenic and uncertain BRCA1 and BRCA2 variants, some of which have not been previously annotated in the public databases. Targeted next-generation sequencing is ready to substitute classic molecular methods to perform genetic testing on the BRCA1 and BRCA2 genes and provides a greater opportunity for more comprehensive testing of at-risk patients.


Asunto(s)
Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias de la Mama/genética , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Neoplasias Ováricas/genética , Adulto , Femenino , Predisposición Genética a la Enfermedad , Humanos , Persona de Mediana Edad
4.
Mol Genet Genomic Med ; 3(5): 396-403, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26436105

RESUMEN

Genetic testing for cystic fibrosis and CFTR-related disorders mostly relies on laborious molecular tools that use Sanger sequencing to scan for mutations in the CFTR gene. We have explored a more efficient genetic screening strategy based on next-generation sequencing (NGS) of the CFTR gene. We validated this approach in a cohort of 177 patients with previously known CFTR mutations and polymorphisms. Genomic DNA was amplified using the Ion AmpliSeq™ CFTR panel. The DNA libraries were pooled, barcoded, and sequenced using an Ion Torrent PGM sequencer. The combination of different robust bioinformatics tools allowed us to detect previously known pathogenic mutations and polymorphisms in the 177 samples, without detecting spurious pathogenic calls. In summary, the assay achieves a sensitivity of 94.45% (95% CI: 92% to 96.9%), with a specificity of detecting nonvariant sites from the CFTR reference sequence of 100% (95% CI: 100% to 100%), a positive predictive value of 100% (95% CI: 100% to 100%), and a negative predictive value of 99.99% (95% CI: 99.99% to 100%). In addition, we describe the observed allelic frequencies of 94 unique definitely and likely pathogenic, uncertain, and neutral CFTR variants, some of them not previously annotated in the public databases. Strikingly, a seven exon spanning deletion as well as several more technically challenging variants such as pathogenic poly-thymidine-guanine and poly-thymidine (poly-TG-T) tracts were also detected. Targeted NGS is ready to substitute classical molecular methods to perform genetic testing on the CFTR gene.

5.
Anticancer Drugs ; 17(9): 1025-30, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17001175

RESUMEN

Ukrain is advertised by the manufacturer as a drug for alternative cancer cures with high activity against progressive Ewing tumors. Using the MTT assay, we compared the cytotoxicity of Ukrain with the cytotoxicity of N,N',N''-triethylenethiophosphoramide (thioTEPA), Chelidonium majus L. alkaloids, doxorubicin, cyclophosphamide and etoposide against four human Ewing tumor cell lines. In addition, we studied the cytotoxicity of thioTEPA combined with C. majus L. alkaloids after 48, 72 and 96 h. All compounds reduced the growth of Ewing tumor cell lines in a dose-dependent manner. The concentrations that reduced cell growth by 50% ranged between 6.2 and 31.1 micromol/l for Ukrain, 1.9 and 26.1 micromol/l for C. majus L. extract, and 1.7 and 448 micromol/l for thioTEPA. The sensitivity profile of Ukrain was comparable to that of the C. majus L. alkaloids, and different from that of thioTEPA, cyclophosphamide, etoposide and doxorubicin. Overall, doxorubicin was the most cytotoxic drug followed by cyclophosphamide. Ukrain and the C. majus L. alkaloids were slightly more cytotoxic than etoposide, while thioTEPA showed the lowest cytotoxicity. Co-exposure of thioTEPA with C. majus L. alkaloids resulted in additive but not in synergistic cytotoxicity. The in-vitro results indicate that the cytotoxicity of Ukrain against Ewing tumors is comparable to that of etoposide. While the latter can be used on the basis of broad clinical experience and known risk-benefit ratio, Ukrain for the present might be considered as a candidate for subsequent drug development by xenograft studies followed by systematic clinical trials.


Asunto(s)
Alcaloides de Berberina/farmacología , Fenantridinas/farmacología , Sarcoma de Ewing/tratamiento farmacológico , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Chelidonium , Relación Dosis-Respuesta a Droga , Doxorrubicina/farmacología , Humanos , Extractos Vegetales/farmacología , Sarcoma de Ewing/patología , Tiotepa/farmacología
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