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1.
Nat Genet ; 19(1): 51-5, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9590288

RESUMEN

Dorsal-ventral limb patterning in vertebrates is thought to be controlled by the LIM-homeodomain protein Lmx1b which is expressed in a spatially and temporally restricted manner along the dorsal-ventral limb axis. Here we describe the phenotype resulting from targeted disruption of Lmx1b. Our results demonstrate that Lmx1b is essential for the specification of dorsal limb fates at both the zeugopodal and autopodal level with prominent phenotypes including an absence of nails and patellae. These features are similar to those present in a dominantly inherited human condition called nail patella syndrome (NPS), which also has renal involvement. Mouse Lmx1b maps to a region syntenic to that of the NPS gene, and kidneys of Lmx1b mutant mice exhibit pathological changes similar to that observed in NPS (refs 5,6). Our results demonstrate an essential function for Lmx1b in mouse limb and kidney development and suggest that NPS might result from mutations in the human LMX1B gene.


Asunto(s)
Proteínas de Homeodominio/genética , Riñón/anomalías , Deformidades Congénitas de las Extremidades/genética , Síndrome de la Uña-Rótula/genética , Animales , ADN Complementario , Proteínas de Homeodominio/química , Humanos , Proteínas con Homeodominio LIM , Ratones , Ratones Mutantes , Microscopía Electrónica de Rastreo , Factores de Transcripción
2.
J Cardiovasc Surg (Torino) ; 49(6): 749-55, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19043389

RESUMEN

AIM: The aim of this study was to evaluate spinal cord injury and mortality resulting from repair of extent I and II thoracoabdominal aneurysm. The authors compared patients operated under mild hypothermia with or without epidural perfusion cooling (EPC) and cerebrospinal fluid drainage (CSFD). METHODS: From 1988 to 2007, 116 patients underwent replacement of the thoracoabdominal aorta; the procedure was performed in 38 patients with the aid of mild hypothermia alone (group A), and in 78 patients with the aid of EPC, mild hypothermia and CSFD (group B). Two catheters for epidural perfusion cooling were inserted in group B, in which one catheter was inserted into the epidural space to infuse chilled saline, and the other was inserted into the subdural space to drain the cerebrospinal fluid and to measure temperature and pressure. There were no significant differences in mean age, etiology of aortic disease, and aneurysm extent between the two groups. RESULTS: There were no significant differences in cardiopulmonary bypass time, the lowest nasopharyngeal temperature and operation time between the two study groups. The incidence of spinal cord injury in group A (16.2%) was significantly higher than in group B (3.8%, P=0.03). Hospital mortality in groups A and B was 10.5% and 2.6%, respectively (P=0.08). There was no significant difference in postoperative complications between the two study groups. CONCLUSION: The combination of EPC and CSFD was effective in lowering the incidence of postoperative spinal cord injury in the repair of extent I and II thoracoabdominal aortic aneurysm.


Asunto(s)
Aneurisma de la Aorta Torácica/cirugía , Líquido Cefalorraquídeo , Drenaje , Espacio Epidural , Hipotermia Inducida/métodos , Anciano , Aneurisma de la Aorta Torácica/patología , Procedimientos Quirúrgicos Cardiovasculares/efectos adversos , Procedimientos Quirúrgicos Cardiovasculares/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Daño por Reperfusión/etiología , Daño por Reperfusión/prevención & control , Isquemia de la Médula Espinal/etiología , Isquemia de la Médula Espinal/prevención & control
3.
Dev Genes Evol ; 206(8): 494-502, 1997 May.
Artículo en Inglés | MEDLINE | ID: mdl-27747376

RESUMEN

The expression pattern of the POU-M1/SGF-3 gene during Bombyx embryogenesis has been analysed using in situ hybridization and immunohistochemistry. At the early embryo retraction stage, both the transcripts and protein were first detected in precursor cells of the prothoracic glands in the labial segment, in the oenocytes in the A1-A8 segments and in invaginated regions in the mandibular and maxillary segments. The invaginated regions in the mandibular segment develop into the abductor plates in the lateral anterior region and the adductor plates in the posterior region. From the latter plates, the salivary glands elongate. The invaginated regions in the maxillary segment develop into the corpora allata in the anterior region and the subbuccal glands in the posterior region, which unite with tissues of the anterior region of the mandibular segment at later stages. After the embryo retraction stage, the transcripts and protein products also become detectable in the silk gland invagination points and, after the blastokinesis stage, the products are restricted to the entire anterior silk glands and to the anterior and middle parts of the middle silk glands. Expression can also be detected in a part of the hindgut, in the tracheal system and in some cells of the central nervous system. These results indicate that POU-M1/SGF-3 might play roles in the development of the silk glands, nervous system, tracheal system and other organs like the prothoracic glands and oenocytes.

4.
Neurosci Lett ; 290(2): 93-6, 2000 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-10936685

RESUMEN

To clarify (1) the localization of flotillins in human brain tissue and (2) the relationship between senile plaque formation and flotillins localization, we performed Western blotting and immunohistochemical analysis. Flotillins 1 and 2 were shown as 48 and 42 kDa bands, respectively, in human brain. The cerebral cortex showed a broad band-like labeling in entire layers. Flotillins were abundant in pyramidal neurons and astrocytes in the white matter. The intensity of the band-like labeling throughout the cortex became stronger with the development of senile plaque formation, and strongest in Alzheimer's disease. These findings suggest that flotillins are associated with progression of Alzheimer pathology.


Asunto(s)
Enfermedad de Alzheimer/patología , Enfermedad de Alzheimer/fisiopatología , Encéfalo/patología , Encéfalo/fisiopatología , Proteínas de la Membrana/metabolismo , Adulto , Anciano , Astrocitos/metabolismo , Astrocitos/patología , Cerebelo/patología , Cerebelo/fisiopatología , Corteza Cerebral/patología , Corteza Cerebral/fisiopatología , Progresión de la Enfermedad , Humanos , Persona de Mediana Edad , Placa Amiloide/metabolismo , Placa Amiloide/patología , Células Piramidales/metabolismo , Células Piramidales/patología
5.
Eur J Pharm Biopharm ; 47(1): 51-9, 1999 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10234527

RESUMEN

A novel enteric coating method was developed. This method involves direct feeding of coating polymer powder and simultaneous spraying of plasticizing agent, without either organic solvent or water, using a centrifugal granulator, fluidized bed, or tablet-coating machine. For film formation, a curing step was then necessary; this involved spraying a small amount (3-8% of core weight) of water or hydroxypropyl methylcellulose solution, followed by heating. Hydroxypropyl methylcellulose acetate succinate was used as the enteric coating polymer, and a combination of triethyl citrate and acetylated monoglyceride was used for plasticization. The coated beads and tablets were evaluated for gastric resistance, intestinal disintegration, and stability, in comparison with beads and tablets from a conventional aqueous coating with the same enteric polymer. The new method required a higher coating amount for gastric resistance compared with the conventional coating, but the processing time was dramatically reduced. The results show that this dry coating method is applicable to the preparation of enteric-coated beads and tablets using commercially available lab-scale apparatus.


Asunto(s)
Metilcelulosa/análogos & derivados , Plastificantes , Comprimidos Recubiertos , Estabilidad de Medicamentos , Microscopía Electrónica de Rastreo , Microesferas , Tamaño de la Partícula , Polvos
6.
J Pharm Sci ; 72(12): 1436-42, 1983 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-6663481

RESUMEN

Four crystalline forms of cimetidine, three anhydrous (forms A, B, and D) and a monohydrate (form C), obtained by slow evaporation of aqueous solutions of varying concentrations were characterized by IR spectroscopy, X-ray powder patterns, dissolution rates in deionized water, and thermal analyses. Among the three anhydrous forms of cimetidine, form A was thermodynamically more stable than the others. The structural conversion of form C into form A on dehydration was confirmed by IR spectroscopy and X-ray powder patterns. The structures of forms C and D were determined using X-ray diffraction. Form D was of spirally curled conformation; it was linked in a head-to-tail arrangement with the neighboring molecules via intermolecular hydrogen bonds between the imidazole nitrogen and guanidine nitrogen atoms. Form C was characterized by its folded conformation due to the weak stacking interaction between the imidazole and guanidine moieties; there was stabilization by double hydrogen bond formation with neighboring molecules and via water molecules of crystallization. The dissolution rate constant in deionized water for form C was approximately 1.29, 1.70, and 1.90 times greater than those measured for forms A, D, and B, respectively. There was a similar relationship among the four forms with respect to the rates of inhibition of stress ulceration. Regarding the molecular conformations of the crystalline forms and the rates of inhibition of stress ulceration, the gauche orientation of the guanidine group relative to the imidazole ring would be the conformation necessary for effective binding to the histamine H2-receptor. The compactly folded conformation of form C appears to be optimal for binding to the active site of the receptor and for clinical efficacy.


Asunto(s)
Cimetidina , Animales , Fenómenos Químicos , Química Física , Cimetidina/uso terapéutico , Cristalización , Modelos Moleculares , Conformación Molecular , Ratas , Solubilidad , Espectrofotometría Infrarroja , Úlcera Gástrica/prevención & control , Termodinámica , Difracción de Rayos X
7.
J Toxicol Sci ; 17(1): 13-9, 1992 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-1593658

RESUMEN

Single-dose toxicological studies of hydrophobically modified hydroxypropyl methylcellulose (HM-HPMC, hydroxypropyl methylcellulose modified with stearylglycidylether) were conducted. A dispersion of HM-HPMC was administered to rats orally or by dermal application at doses up to 900 mg/kg. After the oral administration, the mean body weight of the 900 mg/kg group on the first day after administration was slightly but significantly lower (P less than 0.05) than that of the control group, and one rat had loose stools at 30 min. after the administration. No other abnormalities were noted. In the case of dermal application, no abnormalities were observed. No rats died, and no abnormalities in their organs were found by either route. In conclusion, there was no observed toxicity of HM-HMPC after oral or dermal administration at single dose up to 900 mg/kg under the conditions of these studies.


Asunto(s)
Peso Corporal/efectos de los fármacos , Metilcelulosa/análogos & derivados , Administración Cutánea , Administración Oral , Animales , Femenino , Derivados de la Hipromelosa , Masculino , Metilcelulosa/administración & dosificación , Metilcelulosa/toxicidad , Peso Molecular , Ratas
8.
J Toxicol Sci ; 17(1): 21-9, 1992 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-1593659

RESUMEN

Primary dermal and eye irritation tests of hydrophobically modified hydroxypropyl methylcellulose (HM-HPMC, hydroxypropyl methylcellulose modified with stearylglycidylether), a new cellulose derivative used as a thickener for topical pharmaceuticals and cosmetics, were conducted in rabbits. A dispersion of HM-HPMC (3%) was applied to intact and abraded skins and reactions were observed. A very slight erythema was observed in both skins and this polymer was categorized as a "mild irritant". In the eye irritation test, with a dispersion of the same concentration, it was categorized as "marginal" in unrinsed eyes and "negative" in rinsed eyes.


Asunto(s)
Celulosa/análogos & derivados , Ojo/efectos de los fármacos , Irritantes , Piel/efectos de los fármacos , Administración Cutánea , Animales , Celulosa/administración & dosificación , Celulosa/toxicidad , Femenino , Conejos
9.
Kyobu Geka ; 57(4): 301-6, 2004 Apr.
Artículo en Japonés | MEDLINE | ID: mdl-15071864

RESUMEN

OBJECTIVES: The purpose of this study is to evaluate usefulness of perfusion cooling for regional spinal cord hypothermia during most or all of thoracic or thoracoabdominal aneurysm repair. METHODS: From 1987 to 2003, 103 patients underwent most or all of thoracic or thoracoabdominal aneurysm repair. Forty-eight patients underwent operation using distal aortic perfusion, mild hypothermia and segment sequential repair (group MH). Fifty-five patients underwent the same operation as group MH except epidural perfusion cooling and drainage of cerebrospinal fluid (CSF) [group EC & CSFD]. The aorta was replaced sequentially in segment and several paris of intercostal and lumbar arteries were reconstructed in 2 groups. RESULTS: Cardiopulmonary bypass time of group MH and group EC & CSFD was averaged 235 and 241 minutes, respectively. The lowest CSF temperature in group EC & CSFD was averaged 24.7 degrees C, and the difference between nasopharyngeal and CSF temperature was averaged 6.4 degrees C. The rate of spinal cord injury of group MH and EC & CSFD was 10.4% and 3.6%, respectively. Hospital mortality of group MH and EC & CSFD was 8.3% and 5.5%, respectively. The incidence of spinal cord injury and hospital mortality of group EC & CSFD were decreased compared to them of group MH. CONCLUSION: We conclude that the perfusion cooling of epidural space and CSF drainage are effective method in reducing postoperative spinal cord injury.


Asunto(s)
Aneurisma de la Aorta Abdominal/cirugía , Aneurisma de la Aorta Torácica/cirugía , Drenaje/métodos , Espacio Epidural , Hipotermia Inducida/métodos , Perfusión/métodos , Atención Perioperativa , Complicaciones Posoperatorias/prevención & control , Isquemia de la Médula Espinal/prevención & control , Adulto , Anciano , Anciano de 80 o más Años , Implantación de Prótesis Vascular , Puente Cardiopulmonar , Líquido Cefalorraquídeo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento
12.
Biochem J ; 321 ( Pt 3): 645-53, 1997 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-9032449

RESUMEN

The transcriptional modulator in the fibroin gene intron is composed of multiple octamer-like AT-rich elements, to which several specific DNA-binding proteins named fibroin-modulator-binding proteins (FMBPs) bind. Three major FMBPs in the silk gland were characterized. Two of them (FMBP-2 and -3) were identified as a Fork head homologue (Bm Fkh) and a POU-domain protein (POU-M1) respectively. These factors were expressed in the silk gland with distinct temporal- and spatial-specificities during late larval development as well as during embryogenesis, and did not correlate directly with fibroin gene expression. The other (FMBP-1) appeared to correlate with the expression of the fibroin gene for temporal- and spatial-specificity. These FMBPs also bind to the elements in the upstream modulator. Transcriptional enhancement by both modulators was inhibited by binding competition for these factors with oligonucleotides. These results suggest that expression of the fibroin gene is controlled by co-ordination of these factors with distinct specificities during silk-gland development.


Asunto(s)
Bombyx/metabolismo , Proteínas de Unión al ADN/metabolismo , Fibroínas/genética , Proteínas de Insectos , Proteínas Nucleares/metabolismo , Factores de Transcripción/metabolismo , Animales , Sitios de Unión/genética , Unión Competitiva , Bombyx/embriología , Clonación Molecular , Huella de ADN , Sondas de ADN/química , Factores de Transcripción Forkhead , Regulación del Desarrollo de la Expresión Génica/genética , Hormonas de Insectos/metabolismo , Factores del Dominio POU , Análisis de Secuencia , Activación Transcripcional/fisiología
13.
Chem Pharm Bull (Tokyo) ; 46(11): 1803-6, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9845959

RESUMEN

Pellet film coating has very limited applicability compared with tablet film coating, because of the problem of sticking during fluidized bed operation. We have prepared an extremely low viscosity methylcellulose (MC) (4 mPa.s), and examined its solution and film properties and its suitability for pellet film coating. MC lost its adhesiveness at a relatively high moisture content and pellet film coating could be achieved without agglomeration of the pellets within a reasonable operating time. The coated pellets were covered with a continuous film of MC, and drug release from the coated pellets was as rapid as that from the core. These findings suggest that MC (4 mPa.s) is applicable for pellet film coating in an aqueous system.


Asunto(s)
Metilcelulosa/química , Geles , Solubilidad , Soluciones , Viscosidad
14.
Dev Biol ; 186(1): 46-57, 1997 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-9188752

RESUMEN

Homeotic selector genes determine the identity of each segment and induce the differentiation of segment-specific organs. To analyze how the silk glands of the lepidopteran, Bombyx mori, develop, we cloned and identified two genes that encode the homeodomain and its flanking regions identical to the corresponding regions of Deformed and Sex combs reduced. Using in situ hybridization and immunohistochemistry, we analyzed the expression patterns of these genes during Bombyx embryogenesis. Bombyx Deformed is expressed in the mandibular and maxillary segments, whereas expression of Bombyx Sex combs reduced is first limited to the labial segment and at later stages extended to the anterior part of the prothoracic segment. The expression of Bombyx Sex combs reduced then disappears from the invaginating placodes of silk glands where expression of Bombyx fork head/SGF-1 follows. In the Nc/Nc mutant embryos, which lack the 3' end region of Bombyx Antennapedia, in addition to the expression in the labial segment, the Bombyx Sex combs reduced is expressed ectopically in the thoracic and abdominal regions, and Bombyx fork head/SGF-1 is also ectopically expressed in the T1, T2, and T3 segments, resulting the ectopic induction of the silk gland invaginations. These results suggest that Bombyx homeobox genes such as the Bombyx Deformed and Sex combs reduced are associated with determination of the segment identities and Bombyx Sex combs reduced is involved in the induction of silk gland development.


Asunto(s)
Bombyx/embriología , Proteínas de Drosophila , Regulación del Desarrollo de la Expresión Génica/genética , Genes de Insecto/genética , Proteínas de Insectos/fisiología , Glándulas Salivales/embriología , Factores de Transcripción , Secuencia de Aminoácidos , Animales , Bombyx/genética , Sondas de ADN/química , Drosophila/genética , Embrión no Mamífero/química , Embrión no Mamífero/embriología , Inmunohistoquímica , Hibridación in Situ , Proteínas de Insectos/genética , Datos de Secuencia Molecular
15.
Chem Pharm Bull (Tokyo) ; 45(8): 1350-3, 1997 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9301034

RESUMEN

Hydroxypropyl methylcellulose (HPMC) was selected as a base polymer to develop novel enteric coating agents for acid protection which can dissolve at pH around 4, and was modified with trimellitic acid or maleic acid at various degrees of substitution. These carboxylic acids have higher dissociation constants and higher solubility in water than the carboxylic acids of existing enteric coating polymers. The synthesized polymers were micronized and dispersed in aqueous medium to determine their pKa values by potentiometric titration. The pH of dissolution and the water vapor permeability of the cast films prepared from organic solutions were also evaluated. Hydroxypropyl methylcellulose trimellitate (HPMCT) showed good acid resistance, and the pH at which it dissolves can be controlled in the range of pH 3.5 to 4.5 by varying the content of trimellityl groups and the methoxyl substitution of the base polymer.


Asunto(s)
Celulosa/química , Comprimidos Recubiertos/química , Concentración de Iones de Hidrógeno
16.
Dev Genes Evol ; 206(1): 80-5, 1996 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24173400

RESUMEN

The embryonic expression of Bombyx fkh/SGF-1 gene has been analysed using in situ hybridization and immunohistochemistry. Both transcripts and protein were first detected in the most anterior and posterior regions at the time of germ anlage formation, and were successively expressed in the foregut and hindgut at later stages. A weaker expression was also detected in the elongated midgut. By the time embryo retraction was finished transcripts and protein were also detectable in the invaginated whole silk glands, and after the blastokinesis stage the products were restricted to the middle and posterior silk glands achieving a state required for the SGF-1 distribution for later stages. Expression could also be detected in the central and peripheral nervous systems. From these observations, we propose that Bombyx Fkh/SGF-1 may play a role in organogenesis processes such as those of the gut, silk glands, and nervous systems, act as a region specific homeotic gene, and in spite of clear embryonic developmental differences between Drosophila and Bombyx, two terminals may be determined by region specific genes such as Bombyx fkh/SGF-1 as opposed to segmental development.

17.
Dev Growth Differ ; 40(6): 591-7, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9865969

RESUMEN

Embryonic and larval expression patterns of the sericin-1 gene and its presumed transcription factor, SGF-3/POU-M1, in the silk gland were analyzed by in situ hybridization and immunohistochemistry. The sericin-1 transcripts were first detected at embryonic stage 26 in an increasing gradient pattern in the middle and posterior part of the middle silk gland (MSG), while at the same stage the SGF-3/POU-M1 was already present in the entire anterior silk gland (ASG) and in the MSG but with a decreasing gradient pattern. The latter expression pattern was consistently maintained through all larval stages, while the sericin-1 expression was detected during the feeding stages but disappeared at the molting stages. These observations suggest that, although the SGF-3/POU-M1 was proposed to be a positive transcription factor for the sericin-1 gene, the protein might function in a negative manner on sericin-1 gene transcription. Alternatively, it is also possible that the sericin-1 gene might require another unidentified factor or mediator for in vivo transcription.


Asunto(s)
Bombyx/crecimiento & desarrollo , Bombyx/genética , Proteínas de Unión al ADN/metabolismo , Regulación del Desarrollo de la Expresión Génica , Proteínas de Insectos , Péptidos Cíclicos/genética , Factores de Transcripción/metabolismo , Animales , Northern Blotting , Western Blotting , Inmunohistoquímica , Hibridación in Situ , Larva , Factores del Dominio POU , Sericinas , Factores de Tiempo , Distribución Tisular
18.
Biochem Biophys Res Commun ; 260(2): 459-65, 1999 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-10403790

RESUMEN

In this report we describe the initial characterization of murine, human, and Drosophila hesr-1 (for hairy and enhancer of split related-1) a novel evolutionary conserved family of hairy/enhancer of split homologs. Hesr-1 cDNAs display features typical of hairy and enhancer of split-type bHLH proteins including a N-terminal bHLH domain a conserved orange domain immediately C-terminal to the bHLH region. Despite their similarity to known hairy/enhancer of split homologs, hesr-1 cDNAs are divergent members of the hairy and enhancer of split bHLH family since the degree of sequence identity within the bHLH and their nearest homologs are relatively low. Moreover, the tetrapeptide motif, WRPW, which is found in all hairy and enhancer of split family members, is not present in hesr-1. Rather, a variant of this motif, YRPW, is found. Analysis of embryonic murine hesr-1 expression by in situ hybridization reveals strong expression in the somitic mesoderm, the central nervous system, the kidney, the heart, nasal epithelium, and limbs indicating a role for hesr-1 in the development of these tissues. Like the enhancer of split cDNAs in Drosophila, we show that hesr-1 expression depends critically on signaling through the notch pathway in murine embryos, suggesting that aspects of hesr-1 regulation and function might also be evolutionary conserved.


Asunto(s)
Proteínas de Unión al ADN/genética , Proteínas de Drosophila , Drosophila/genética , Proteínas de Insectos/genética , Proteínas Represoras/genética , Factores de Transcripción/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico , ADN Complementario , Proteínas de Unión al ADN/metabolismo , Desarrollo Embrionario y Fetal/genética , Regulación del Desarrollo de la Expresión Génica , Humanos , Proteínas de Insectos/metabolismo , Proteínas de la Membrana/metabolismo , Ratones , Datos de Secuencia Molecular , Receptores Notch , Proteínas Represoras/metabolismo , Homología de Secuencia de Aminoácido , Transducción de Señal , Factores de Transcripción/metabolismo
19.
Nucleic Acids Res ; 24(12): 2387-94, 1996 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-8710511

RESUMEN

The Drosophila Fork head protein participates in salivary gland formation, since salivary glands are missing in fork head embryos. Here we show that the fork head encoded protein binds to an upstream regulatory region of the larval salivary gland glue protein gene Sgs3. Mobility shift assay in the presence of an anti-Fork head antibody demonstrated that the Fork head factor interacts with the TGTTTGC box shown to be involved in tissue-specific Sgs3 expression. Experiments employing a set of oligonucleotide competitors revealed that Fork head binding was prevented by the same single base substitutions that were previously shown to interfere with the TGTTTGC element function in vivo. Furthermore, the anti-Fork head antibody bound to >60 sites of polytene chromosomes, including the puffs of all Sgs genes and Fork head protein was detected in the nuclei of salivary glands of larvae of all examined stages. These data provide experimental evidence for the hypothesis that the protein encoded by the fork head gene is required initially for salivary gland formation and is utilized subsequently in the control of larval genes specifically expressed in this organ.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Drosophila/genética , Regulación del Desarrollo de la Expresión Génica , Proteínas del Pegamento Salivar de Drosophila/genética , Proteínas Nucleares/metabolismo , Factores de Transcripción/metabolismo , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Sitios de Unión , Bombyx , Cromosomas , ADN , Factores de Transcripción Forkhead , Larva , Masculino , Datos de Secuencia Molecular , Conejos , Secuencias Reguladoras de Ácidos Nucleicos , Glándulas Salivales/metabolismo
20.
Virology ; 217(1): 332-7, 1996 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-8599219

RESUMEN

T3 and T7 phages package recombinant plasmids carrying DNA necessary for DNA packaging (the pac sequences) of T3 and T7, respectively. Packaging is specific between T3 and T7. The pac sequence has a bipartite structure, consisting of target sequences for processing of concatemeric DNA (pac C) and its left side flanking sequence containing a promoter for phage RNA polymerase (pac B). To determine the sequences responsible for the specificity of plasmid DNA packaging, plasmids chimeric for the pac B and pac C sequences of T3 and T7 were constructed. Analysis of packaging of the chimeric plasmid DNAs showed that pac B is responsible for the packaging specificity of T3 and T7 DNAs. Plasmids carrying the genetic right end of T3 and T7 DNA interfered with the growth of T3 and T7 phages, respectively. Interference was specific between T3 and T7. pac B and sequences between pac B and pac C, but not pac C, were responsible for the interference. The specificity of interference was determined by pac B and sequences responsible for interference were partially defined.


Asunto(s)
Bacteriófago T3/genética , Bacteriófago T7/genética , ADN Viral/fisiología , Ensamble de Virus/genética , Bacteriófago T3/fisiología , Bacteriófago T7/fisiología , Secuencia de Bases , ADN Recombinante , ADN Viral/química , Datos de Secuencia Molecular , Conformación de Ácido Nucleico , Plásmidos , Interferencia Viral
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