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2.
Science ; 271(5246): 209-12, 1996 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-8539622

RESUMEN

PHO4, a transcription factor required for induction of the PHO5 gene in response to phosphate starvation, is phosphorylated by the PHO80-PHO85 cyclin-CDK (cyclin-dependent kinase) complex when yeast are grown in phosphate-rich medium. PHO4 was shown to be concentrated in the nucleus when yeast were starved for phosphate and was predominantly cytoplasmic when yeast were grown in phosphate-rich medium. The sites of phosphorylation on PHO4 were identified, and phosphorylation was shown to be required for full repression of PHO5 transcription when yeast were grown in high phosphate. Thus, phosphorylation of PHO4 by PHO80-PHO85 turns off PHO5 transcription by regulating the nuclear localization of PHO4.


Asunto(s)
Núcleo Celular/metabolismo , Quinasas Ciclina-Dependientes/metabolismo , Ciclinas/metabolismo , Proteínas de Unión al ADN , Proteínas Fúngicas/metabolismo , Proteínas de Transporte de Fosfato , Proteínas Represoras , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Factores de Transcripción/metabolismo , Secuencia de Aminoácidos , Medios de Cultivo , Citoplasma/metabolismo , Dipéptidos/metabolismo , Regulación Fúngica de la Expresión Génica , Proteínas de Transporte de Membrana/genética , Datos de Secuencia Molecular , Mutación , Fosfatos/metabolismo , Fosforilación , Saccharomyces cerevisiae/genética
3.
AIDS Res Hum Retroviruses ; 7(12): 991-8, 1991 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1667477

RESUMEN

Recombinant fowlpox viruses (FPV) containing the env or gag-pol genes of simian immunodeficiency virus from macaques (SIVmac) were constructed. The env, gag, and pol-encoded polypeptides were efficiently expressed and processed in avian cells productively infected with FPV as well as in mammalian cells, in which FPV infection is abortive. In addition, the recombinant FPV expressing the gag-pol genes directed the formation of defective, lentivirus-like particles which were released into the culture medium of infected cells. Coinfection of cells with the env and gag-pol recombinant viruses resulted in the generation of particles containing SIVmac envelope glycoprotein. The applications of this system to vaccine development are discussed.


Asunto(s)
Virus de la Viruela de las Aves de Corral/genética , Proteínas de los Retroviridae/biosíntesis , Virus de la Inmunodeficiencia de los Simios/genética , Animales , Secuencia de Bases , Línea Celular , Células Cultivadas , Embrión de Pollo , ADN Recombinante , Genes env , Genes gag , Genes pol , Vectores Genéticos , Microscopía Electrónica , Datos de Secuencia Molecular , Regiones Promotoras Genéticas , Virus de la Inmunodeficiencia de los Simios/crecimiento & desarrollo , Virus de la Inmunodeficiencia de los Simios/ultraestructura
4.
Arq Neuropsiquiatr ; 36(4): 319-26, 1978 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-109066

RESUMEN

An electrophysiological study has been made of the thenar, hypothenar, soleus and extensor digitorum brevis muscles and their inervation in 90 patients with chronic Chagas' disease. Some of them showed a reduced number of functional motor units with increased size of many of the surviving units. No decremental muscle response was found to repetitive nerve stimulation. Motor and sensory conduction velocities as well as motor terminal latencies were on the normal range. These findings suggested that the muscle changes resulted from a primary defect of the alpha spinal motoneurone soma.


Asunto(s)
Enfermedad de Chagas/fisiopatología , Músculos/inervación , Adolescente , Adulto , Niño , Electrofisiología , Humanos , Persona de Mediana Edad , Placa Motora/patología , Neuronas Motoras/patología , Neuronas Motoras/fisiología , Degeneración Nerviosa , Conducción Nerviosa , Nervios Periféricos/fisiopatología
11.
Mol Ecol ; 16(3): 553-68, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17257113

RESUMEN

The mountain pine beetle Dendroctonus ponderosae is a native species currently experiencing large-scale outbreaks in western North American pine forests. We sought to describe the pattern of genetic variation across the range of this species, to determine whether there were detectable genetic differences between D. ponderosae occupying different host trees in common localities, and to determine whether there was molecular evidence for a past demographic expansion. Using a combination of amplified fragment length polymorphism (AFLP) and mitochondrial sequencing analyses, we found evidence of genetic structuring among populations that followed a broad isolation-by-distance pattern. Our results suggest that the geographical pattern of gene flow follows the core distribution of the principal D. ponderosae host species, around rather than across the Great Basin and Mojave Deserts. Patterns of haplotype diversity and divergence were consistent with a range-wide population expansion. This signal was particularly pronounced in the northern part of the species' range, where outbreak activity is currently increasing. Using AFLP markers, we were unable to detect significant differences among groups of insects sampled from different host trees in common locations. Incidentally, we found that a large proportion of the polymorphic AFLP markers were gender-specific, occurring only in males. While we did not include these markers in our analyses, this finding warrants further investigation.


Asunto(s)
Escarabajos/genética , Variación Genética , Polimorfismo Genético , Árboles , Animales , Escarabajos/clasificación , ADN Mitocondrial/genética , Femenino , Geografía , Masculino , Filogenia , Reacción en Cadena de la Polimerasa , Análisis de Secuencia de ADN
12.
Br J Urol ; 66(5): 455-8, 1990 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-2249110

RESUMEN

Family screening was offered to the relatives of 57 patients with duplex renal systems and this resulted in the detection of another 37 cases. A further 5 first degree relatives had abnormal intravenous urography, so that 25% of the screened relatives had significant renal abnormalities. It is suggested that there may be a place for screening the whole family if renal tract duplex is detected.


Asunto(s)
Familia , Riñón/anomalías , Adulto , Femenino , Genes Dominantes , Humanos , Riñón/diagnóstico por imagen , Masculino , Linaje , Radiografía
13.
Br Med J ; 1(5642): 483-5, 1969 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-5764251

RESUMEN

Turner's infantile phenotype is a term used to describe infants with stigmata suggestive of Turner's syndrome. These include brawny oedema of the feet, loose neck folds, and a characteristic facies. Ten cases are described in this report. Four of these had a similar facial appearance and three had serous effusions. Two of the latter died and at necropsy no cardiac, vascular, or renal cause for the effusions was found, but the gonads in each were macroscopically reduced in size and microscopically were grossly abnormal.


Asunto(s)
Síndrome de Turner/diagnóstico , Edema/etiología , Cara , Femenino , Humanos , Lactante , Recién Nacido , Ovario/patología , Fenotipo , Cromatina Sexual
14.
Cell ; 78(1): 137-47, 1994 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-8033205

RESUMEN

We show that the activities of two Ets-related transcription factors required for normal eye development in Drosophila, pointed and yan, are regulated by the Ras1/MAPK pathway. The pointed gene codes for two related proteins, and we show that one form is a constitutive activator of transcription, while the activity of the other form is stimulated by the Ras1/MAPK pathway. Mutation of the single consensus MAPK phosphorylation site in the second form abrogates this responsiveness. yan is a negative regulator of photoreceptor determination, and genetic data suggest that it acts as an antagonist of Ras1. We demonstrate that yan can repress transcription and that this repression activity is negatively regulated by the Ras1/MAPK signal, most likely through direct phosphorylation of yan by MAPK.


Asunto(s)
Proteínas de Unión al ADN/fisiología , Proteínas de Drosophila , Drosophila/genética , Quinasas MAP Reguladas por Señal Extracelular , Proteínas del Ojo/fisiología , Proteínas Proto-Oncogénicas/fisiología , Proteínas Represoras , Transducción de Señal/fisiología , Factores de Transcripción/fisiología , Animales , Proteínas Quinasas Dependientes de Calcio-Calmodulina/genética , Proteínas de Unión al ADN/genética , Ojo/crecimiento & desarrollo , Proteínas del Ojo/genética , Regulación de la Expresión Génica , Genes de Insecto/genética , Genes ras/genética , Modelos Biológicos , Morfogénesis , Proteínas del Tejido Nervioso , Fenotipo , Células Fotorreceptoras de Invertebrados/crecimiento & desarrollo , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas p21(ras)/genética , Factores de Transcripción/genética , Transcripción Genética/genética
15.
Proc Natl Acad Sci U S A ; 92(14): 6557-61, 1995 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-7604032

RESUMEN

The glass gene is required for proper photo-receptor differentiation during development of the Drosophila eye glass codes for a DNA-binding protein containing five zinc fingers that we show is a transcriptional activator. A comparison of the sequences of the glass genes from two species of Drosophila and a detailed functional domain analysis of the Drosophila melanogaster glass gene reveal that both the DNA-binding domain and the transcriptional-activation domain are highly conserved between the two species. Analysis of the DNA-binding domain of glass indicates that the three carboxyl-terminal zinc fingers alone are necessary and sufficient for DNA binding. We also show that a deletion mutant of glass containing only the DNA-binding domain can behave in a dominant-negative manner both in vivo and in a cell culture assay that measures transcriptional activation.


Asunto(s)
Proteínas de Unión al ADN/biosíntesis , Proteínas de Drosophila , Drosophila melanogaster/metabolismo , Drosophila/metabolismo , Factores de Transcripción/biosíntesis , Dedos de Zinc , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Sitios de Unión , Línea Celular , Cloranfenicol O-Acetiltransferasa/análisis , Cloranfenicol O-Acetiltransferasa/biosíntesis , ADN/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Drosophila/genética , Drosophila melanogaster/genética , Ojo/ultraestructura , Expresión Génica , Genes de Insecto , Microscopía Electrónica de Rastreo , Datos de Secuencia Molecular , Oligodesoxirribonucleótidos , Homología de Secuencia de Aminoácido , Transactivadores/biosíntesis , Transactivadores/metabolismo , Transcripción Genética , Transfección
16.
Transfusion ; 41(7): 928-32, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11452162

RESUMEN

BACKGROUND: The FDA has approved the storage of frozen RBCs at -80 degrees C for 10 years and the postwash storage at 4 degrees C for no more than 24 hours. The 4 degrees C postwash storage period is limited to 24 hours, because the current deglycerolization systems are functionally open systems. STUDY DESIGN AND METHODS: Two units of RBCs were collected from each of 13 healthy male volunteers. The RBCs were collected in CP2D by the FDA-approved protocol for an automated apheresis device (MCS, LN8150, Haemonetics) and were stored at 4 degrees C in AS-3 for 6 days. Using a single disposable glycerolization set in an automated, functionally closed system (ACP 215, Haemonetics) each unit was transferred to a 1000-mL PVC plastic bag and glycerolized to a concentration of 40-percent (wt/vol) glycerol and frozen at -80 degrees C. A single disposable deglycerolization set in the ACP 215 was used to deglycerolize the 2 units from the same donor. The deglycerolized RBCs were stored at 4 degrees C in AS-3 for as long as 21 days. RESULTS: The mean +/- SD freeze-thaw-wash recovery value was 89.4 +/- 3 percent. The residual hemolysis in the RBCs stored at 4 degrees C in AS-3 for 21 days after deglycerolization was 0.9 +/- 0.2 percent, and the units were negative for both aerobic and anaerobic bacteria. The mean Nageotte WBC count was 9 x 10(6) per unit. When the deglycerolized RBCs were given as an autologous transfusion after storage at 4 degrees C in AS-3 for the 7- to 18-day period, the mean +/- SD 24-hour posttransfusion survival was 77 +/- 7 percent, and the index of therapeutic effectiveness was 69 +/- 8 percent. CONCLUSION: Two units of human RBCs collected from a single donor by apheresis in the MCS using an LN8150 set can be glycerolized sequentially with a single disposable set and deglycerolized sequentially with another single disposable set in the ACP 215. The previously frozen RBCs stored in AS-3 for 7 to 18 days at 4 degrees C had acceptable hemolysis and an acceptable mean 24-hour posttransfusion survival value and index of therapeutic effectiveness.


Asunto(s)
Adenina , Eliminación de Componentes Sanguíneos , Criopreservación/métodos , Envejecimiento Eritrocítico , Transfusión de Eritrocitos , Glucosa , Glicerol/metabolismo , Glicerol/farmacología , Manitol , Cloruro de Sodio , Separación Celular/instrumentación , Liofilización/métodos , Humanos , Factores de Tiempo
17.
Development ; 119(3): 855-65, 1993 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8187644

RESUMEN

The glass gene encodes a DNA-binding zinc-finger protein required for the development of Drosophila photoreceptor cells and which appears to regulate a number of genes specifically expressed in photoreceptors. We have generated monoclonal antibodies to Glass and used them to examine Glass distribution during development. Glass is expressed in all cell types of the developing eye and in all other organs that contain photoreceptor cells in Drosophila, including a small number of cells in the brain. We altered the normal pattern of glass expression by placing the gene under the control of the hsp70 promoter. Our results suggest that nonphotoreceptor cells are restricted in their response to Glass expression. In an effort to discover the mechanism of this restriction, we examined the expression of a number of reporter gene constructs. Our results suggest that nonsensory cells are unable to express certain reporter constructs in response to Glass expression because another DNA-binding factor represses Glass activity in nonsensory cells.


Asunto(s)
Proteínas de Unión al ADN/genética , Proteínas de Drosophila , Drosophila/embriología , Ojo/embriología , Expresión Génica/fisiología , Células Fotorreceptoras de Invertebrados/embriología , Animales , Secuencia de Bases , Cartilla de ADN , Proteínas de Unión al ADN/fisiología , Drosophila/genética , Regulación de la Expresión Génica/fisiología , Genes Reporteros/fisiología , Inmunohistoquímica , Datos de Secuencia Molecular
18.
Infect Immun ; 35(2): 476-82, 1982 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-6276304

RESUMEN

Strains of Streptococcus ferus isolated from the oral cavities of wild rodents inhabiting sucrose-rich and sucrose-poor environments have many traits in common with the "mutans" streptococci. Thus, S. ferus HD3 and 8S1, like cariogenic S. sobrinus 6715-13, from adherent, alpha (1 leads to 3) glucopyranosyl-glucose linkage-rich, plaquelike deposits in vitro and in vivo through the action of constitutive glucosyltransferase(s) enzymes on sucrose, produce and degrade intracellular polysaccharide, produce short-chain fatty acids from the catabolism of mono- and disaccharides, carry the c antigen of S. mutans, and penetrate, persist, and proliferate in a sucrose-augmented fashion in the oral cavities of specific-pathogen-free rodent caries models. However, unlike infection with common S. mutans, infection with tested S. ferus strains does not cause caries. This avirulence appeared to result more from the reduced aciduricity of S. ferus than from differences in glucosyltransferase complements. Studies showed that despite generally similar growth rates and extracellular glucan syntheses, the acidogenic metabolism of S. ferus was more inhibited by declining environmental pH than was cariogenic S. sobrinus 6715-13 and that, in vitro, less hydroxyapatite was solubilized by S. ferus metabolic end products. The physiology of these S. ferus strains demonstrated that, in addition to plaque formation and acid production, acid tolerance was crucial to the carious process.


Asunto(s)
Muridae/microbiología , Streptococcus/fisiología , Aglutinación , Animales , Dextranasa/metabolismo , Durapatita , Fructosa/metabolismo , Glucanos/biosíntesis , Glucosa/metabolismo , Glucosiltransferasas/metabolismo , Concentración de Iones de Hidrógeno , Hidroxiapatitas/metabolismo , Sacarosa/metabolismo
19.
J Inherit Metab Dis ; 2(4): 89-92, 1980.
Artículo en Inglés | MEDLINE | ID: mdl-6796766

RESUMEN

A new case of alpha-aminoadipic aciduria had an apparent immunodeficiency and died at the age of 4 months. The urine contained large amounts of alpha-aminoadipate and smaller quantities of alpha-keto- and alpha-hydroxyadipate. Post mortem, the highest concentrations of alpha-aminoadipate were found in liver and kidney. Enzymatic studies on liver and cultured fibroblasts failed to demonstrate the expected deficiency of alpha-amino-adipate aminotransferase, a result perhaps explicable by the presence of cytoplasmic aminotransferase activity.


Asunto(s)
Ácido 2-Aminoadípico/orina , Errores Innatos del Metabolismo de los Aminoácidos/diagnóstico , Aminoácidos Dicarboxílicos/orina , Enfermedades del Recién Nacido/diagnóstico , Ácido 2-Aminoadípico/sangre , Errores Innatos del Metabolismo de los Aminoácidos/metabolismo , Aminoácidos/orina , Femenino , Estudios de Seguimiento , Humanos , Recién Nacido
20.
Development ; 122(12): 3745-54, 1996 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9012496

RESUMEN

Spatially regulated activation of the Drosophila epidermal growth factor (EGF) receptor by its ligand, Gurken, is required for establishment of the dorsal/ventral axis of the oocyte and embryo. During mid-oogenesis, Gurken is concentrated at the dorsal-anterior of the oocyte and is thought to activate the EGF receptor pathway in adjacent follicle cells. In response to this signal, dorsal follicle cell fate is determined. These cells further differentiate into either appendage-producing or midline cells, resulting in patterning in the dorsal follicle cell layer. We show here that Pointed, an ETS transcription factor, is required in dorsal follicle cells for this patterning. Loss of pointed results in the loss of midline cells and an excess of appendage-forming cells, a phenotype associated with overactivation of the EGF receptor pathway in the dorsal region. Overexpression of pointed leads to a phenotype similar to that generated by loss of the EGF receptor pathway. This suggests that Pointed normally down-regulates EGF receptor signaling in the midline to generate patterning in the dorsal region. Interestingly, pointed expression is induced by the EGF receptor pathway. These data indicate a novel antagonistic function for Pointed in oogenesis; in response to activation of the EGF receptor, pointed is expressed and negatively regulates the EGF receptor pathway, possibly by integrating information from a second pathway.


Asunto(s)
Tipificación del Cuerpo/fisiología , Proteínas de Drosophila , Receptores ErbB/metabolismo , Oogénesis/fisiología , Proteínas Proto-Oncogénicas/metabolismo , Factores de Transcripción/metabolismo , Factor de Crecimiento Transformador alfa , Animales , Proteínas de Unión al ADN , Drosophila melanogaster/citología , Drosophila melanogaster/embriología , Drosophila melanogaster/crecimiento & desarrollo , Femenino , Hormonas de Insectos/metabolismo , Modelos Biológicos , Morfogénesis , Proteínas del Tejido Nervioso , Transducción de Señal , Distribución Tisular , Factores de Crecimiento Transformadores/metabolismo
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