RESUMEN
Genome-wide microarray analysis (Affymetrix array) was used (i) to determine whether only one gene, the cytochrome P450 enzyme Cyp6g1, is differentially transcribed in dichlorodiphenyltrichloroethane (DDT)-resistant vs. -susceptible Drosophila; and (ii) to profile common genes differentially transcribed across a DDT-resistant field isolate [Rst(2)DDT(Wisconsin)] and a laboratory DDT-selected population [Rst(2)DDT(91-R)]. Statistical analysis (ANOVA model) identified 158 probe sets that were differentially transcribed among Rst(2)DDT(91-R), Rst(2)DDT(Wisconsin), and the DDT-susceptible genotype Canton-S (P < 0.01). The cytochrome P450 Cyp6a2 and the diazepam-binding inhibitor gene (Dbi) were over transcribed in the two DDT-resistant genotypes when compared to the wild-type Drosophila, and this difference was significant at the most stringent statistical level, a Bonferroni correction. The list of potential candidates differentially transcribed also includes 63 probe sets for which molecular function ontology annotation of the probe sets did not exist. A total of four genes (Cyp6a2, Dbi, Uhg1, and CG11176) were significantly different (P < 5.6 e(-06)) between Rst(2)DDT(91-R) and Canton-S. Additionally, two probe sets encoding Cyp12d1 and Dbi were significantly different between Rst(2)DDT(Wisconsin) and Canton-S after a Bonferroni correction. Fifty-two probe sets, including those associated with pesticide detoxification, ion transport, signal transduction, RNA transcription, and lipid metabolism, were commonly expressed in both resistant lines but were differentially transcribed in Canton-S. Our results suggest that more than Cyp6g1 is overtranscribed in field and laboratory DDT-resistant genotypes, and the number of commonalities suggests that similar resistance mechanisms may exist between laboratory- and field-selected DDT-resistant fly lines.
Asunto(s)
DDT/metabolismo , Drosophila/genética , Resistencia a Medicamentos/genética , Perfilación de la Expresión Génica , Animales , Drosophila/metabolismo , Enzimas/genética , Enzimas/metabolismo , Metabolismo de los LípidosRESUMEN
We describe here the first systematic work to discover insect genes involved in food breakdown using a cDNA library enriched for gut-expressed transcripts from Callosobruchus maculatus. A total of 1056 clones were screened for cDNA insert-containing plasmids, and 503 nonredundant open reading frames were discovered. Twenty-three inferred genes potentially involved in digestive processes in cowpea weevil were identified, including proteinases and amylases. The predicted catalytic sites were identified in the inferred cysteine and aspartic acid proteinases, and in alpha-amylases. Transcriptome analysis of the cowpea bruchid will potentially permit gene discovery in other beetles, an insect order of major economic and ecological importance that is poorly represented in genomic databases.
Asunto(s)
Escarabajos/enzimología , Endopeptidasas/genética , Proteínas de Insectos/genética , alfa-Amilasas/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Escarabajos/genética , Escarabajos/metabolismo , ADN Complementario/genética , ADN Complementario/metabolismo , Etiquetas de Secuencia Expresada , Datos de Secuencia Molecular , Sistemas de Lectura Abierta , Reacción en Cadena de la Polimerasa , Alineación de SecuenciaRESUMEN
Previous studies have shown that the major metabolic resistance locus in the insecticide-resistant Drosophila line Rst(2)DDT(Wisconsin) maps between the markers cn and vg on chromosome 2. Six cytochrome P450 genes exist in this region. We investigated the expression levels of these P450 genes in DDT-resistant and -susceptible fly lines. We report: (i) DDT resistance is significant (> 30-fold) and dominant, (ii) resistance is reduced by the cytochrome P450 inhibitor PBO, (iii) there is constitutive over-expression relative to susceptible flies of two genes encoding cytochrome P450 enzymes within the cn-vg region (CYP6G1 = 4.3-fold; CYP12D1 = 6.0-fold), and (iv) exposure to DDT results in an increased expression of only one of these two P450 genes (CYP12D1 > or = 6-fold above constitutive resistant fly baselines).
Asunto(s)
Sistema Enzimático del Citocromo P-450/biosíntesis , DDT , Drosophila/enzimología , Regulación Enzimológica de la Expresión Génica/genética , Animales , Northern Blotting , Inhibidores Enzimáticos del Citocromo P-450 , Sistema Enzimático del Citocromo P-450/genética , Sistema Enzimático del Citocromo P-450/metabolismo , ADN/química , ADN/genética , Drosophila/genética , Drosophila/metabolismo , Inducción Enzimática , Inhibidores Enzimáticos/farmacología , Resistencia a los Insecticidas/genética , Sinergistas de Plaguicidas , Butóxido de Piperonilo/farmacología , Reacción en Cadena de la PolimerasaRESUMEN
The hamartoma is a benign tumor resulting of a mixture of normal and mature tissues and cells, sitting on an organ or tissue showing identical cell components. From the perusal done of the bibliography they appear as rare malformations basically compound of fibrous tissue, fat, acini of salivary glands and smooth muscle.
Asunto(s)
Hamartoma/diagnóstico , Neoplasias de la Lengua/diagnóstico , Anciano , Femenino , Hamartoma/patología , Humanos , Lengua/patología , Neoplasias de la Lengua/patologíaRESUMEN
Chordomas of the skull base are neoplasms derived from persistent embryologic remnants. In spite of its histologic classification as benign tumors, the site and the adverse possibilities of the management its behaviour is malignant like. The case here referred to was localized in the basioccipital region and protruded in the rhinopharynx. Perusal of the bibliography and prognostic assessment of these type of patients.
