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1.
Acta Medica Philippina ; : 66-71, 2022.
Artículo en Inglés | WPRIM (Pacífico Occidental) | ID: wpr-988168

RESUMEN

@#A family was studied in which three members in the sibship belonging to the fourth generation were found to have Rotor’s syndrome. More detailed examinations including blood studies, liver profiles, oral cholecystograms, and liver biopsies where performed on the affected siblings. The results were related to what is at present known about the features and mechanisms of Rotor’s syndrome, pari passu the current concept of bilirubin metabolism. It is suggested that the constant finding, and possibly the only characteristic one in Rotor’s syndrome, is the absence of abnormal hepatic cell pigmentation. Pedigree analysis of the present family shows that the transmission of this disorder may be conditioned by an autosomal recessive gene.


Asunto(s)
Hiperbilirrubinemia Hereditaria
2.
Insects ; 11(11)2020 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-33202584

RESUMEN

The natural presence of entomopathogenic nematodes (EPNs) has been investigated in the Piedmont region (Northern Italy) in areas infested by the Japanese beetle Popillia japonica. Thirty-nine out of 155 soil samples (25.2%) were positive for EPNs. Most of the samples contained only steinermatids (92.3%), 5.1% contained heterorhabditids, and one sample (2.6%) contained both genera. All the recovered isolates were identified at species level both morphologically and molecularly. Steinernema carpocapsae was the most abundant and it was mainly distributed in open habitats, such as perennial meadows, uncultivated soils, and cropland, characterized by sandy loam soil texture and acidic pH. Steinernema feltiae has been found associated mainly with closed habitats such as coniferous and deciduous woodland, characterized by sandy loam-texture and extremely acidic soil. The three isolates of Heterorhabditis bacteriophora were collected only in open habitats (perennial meadows and uncultivated fields) characterized by strongly acidic soils with sandy loam texture. The virulence of all EPN natural strains was evaluated by laboratory assays against P. japonica third-instar larvae collected during two different periods of the year (spring, autumn). The results showed that larval mortality was higher for pre-wintering larvae than post-wintering ones. The five more promising EPN isolates were tested in the semi-field assay in which H. bacteriophora natural strains have been shown to be more efficient in controlling P. japonica grubs. All of these results are finally discussed considering the use of these natural EPNs as biological control agents against P. japonica, within an eco-friendly perspective of management.

3.
Insects ; 11(9)2020 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-32927750

RESUMEN

The jasmine lacebug Corythauma ayyari is a pest of cultivated and ornamental plants mainly associated to Jasminum spp. This invasive insect is native to Asia, and it has been recently introduced in several countries, mainly within the Mediterranean basin. Here, we updated the known distribution of this species, including five new Italian regions (Liguria, Tuscany, Latium, Apulia, and Calabria); Salamis Island in Greece, and the Occitanie region in France. Citizen-science data have significantly contributed to the knowledge on species distribution, and the online platform for sharing biodiversity information can represent an effective tool for the early detection. Molecular analyses revealed that the specimens collected in Peninsular Italy and Sicily belong to a unique clade, suggesting the possibility of a single introduction, whereas those from Menton (France) and Calabria (Southern Italy) are separated from the others and probably originate from separated introductions.

4.
Biopreserv Biobank ; 16(3): 207-216, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29746148

RESUMEN

Cryopreservation of viable cells and cell materials is being developed for biological and biopharmaceutical applications. The inhibition of ice formation during the cooling and warming phase of vitrified living biological samples is important for their survival. The tendency to form glasses (glass transition temperature, Tg) upon cooling in the vitrification solution and the stability of the amorphous state upon warming to determine the critical cooling rate (Vccr) and critical warming rates (Vcwr) are evaluated. The study of thermal properties of ethylene glycol (EG) and 1,2-propanediol (PD) solutions were performed to improve vitrification through better understanding of their molecular mobility and viscosity. Two sets of aqueous solutions were tested. In group A, 35% EG (w/w) was added to different PD concentrations (5%, 10%, and 15%). In group B, 20% PD (w/w) was combined with varying concentrations of EG (20%, 24%, 27%, and 30%). Using the semiempirical model of Boutron, the values of Vccr and Vcwr for group A were 10, 8, <2.5°C/min, and 1.65 × 105, 678, 32°C/min, respectively. For group B, the values were 24, 10, <2.5, <2.5°C/min, and 9.5 × 103, 144, 48, 7°C/min, respectively. While the values of Vccr and Vcwr for 40% EG were 123 and 8.84 × 105°C/min, respectively. The methyl group in PD enhanced the vitreous state, lowering the melting point. Adding a small concentration of PD (3%) to VM3 vitrification solution improved and increased the Tg and enhanced their thermal stability. Analyzing the thermal properties of cryoprotectant is useful when designing the cryopreservation protocols.

5.
Syst Parasitol ; 94(8): 915-926, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28815424

RESUMEN

A new species of mermithid nematode, Hexamermis popilliae n. sp. (Nematoda: Mermithidae) is described from the Japanese beetle Popillia japonica Newman in Italy, an area of new introduction for this invasive pest. The combination of the following characters separates H. popilliae from other members of the genus Hexamermis Steiner, 1924: adult head obtuse; amphidial pouches slightly posterior to lateral head papillae in female but adjacent to lateral head papillae in males; amphidial openings large, well developed; amphidial pouches elliptical in females and oblong in males; cuticular vulvar cone well developed, vulvar lips greatly reduced or lacking, vagina curved at tip where meeting uteri, without reverse bend (not S-shaped), spicules slightly curved, with a slight bend in the basal portion, approximately equal to body width at cloaca. This is the first record of a species of Hexamermis parasitizing the Japanese beetle Popillia japonica. The only previous mention of mermithid nematodes from P. japonica was an undescribed species of Psammomermis in North America. Hexamermis popilliae will be evaluated as a potential biological control agent in an integrated control program of the Japanese beetle in Italy.


Asunto(s)
Escarabajos/parasitología , Nematodos/clasificación , Animales , Femenino , Especies Introducidas , Italia , Masculino , Nematodos/anatomía & histología , Especificidad de la Especie
6.
Forensic Sci Int Genet ; 19: 212-220, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26275611

RESUMEN

The capability of DNA laboratories to perform genotyping procedures from post-mortem remains, including those that had undergone putrefaction, continues to be a challenge in the Philippines, a country characterized by very humid and warm conditions all year round. These environmental conditions accelerate the decomposition of human remains that were recovered after a disaster and those that were left abandoned after a crime. When considerable tissue decomposition of human remains has taken place, there is no other option but to extract DNA from bone and/or teeth samples. Routinely, femur shafts are obtained from recovered bodies for human identification because the calcium matrix protects the DNA contained in the osteocytes. In the Philippines, there is difficulty in collecting femur samples after natural disasters or even human-made disasters, because these events are usually characterized by a large number of fatalities. Identification of casualties is further delayed by limitation in human and material resources. Hence, it is imperative to test other types of biological samples that are easier to collect, transport, process and store. We analyzed DNA that were obtained from body fluid, bone marrow, muscle tissue, clavicle, femur, metatarsal, patella, rib and vertebral samples from five recently deceased untreated male cadavers and seven male human remains that were embalmed, buried for ∼ 1 month and then exhumed. The bodies had undergone different environmental conditions and were in various stages of putrefaction. A DNA extraction method utilizing a detergent-washing step followed by an organic procedure was used. The utility of bone marrow and vitreous fluid including bone marrow and vitreous fluid that was transferred on FTA(®) cards and subjected to autosomal STR and Y-STR DNA typing were also evaluated. DNA yield was measured and the presence or absence of PCR inhibitors in DNA extracts was assessed using Plexor(®)HY. All samples were amplified using PowerPlex(®)21 and PowerPlexY(®)23 systems and analyzed using the AB3500 Genetic Analyzer and the GeneMapper(®) ID-X v.1.2 software. PCR inhibitors were consistently detected in bone marrow, muscle tissue, rib and vertebra samples. Amplifiable DNA was obtained in a majority of the samples analyzed. DNA recovery from 0.1g biological material was adequate for successful genotyping of most of the non-bone and bone samples. Complete DNA profiles were generated from bone marrow, femur, metatarsal and patella with 0.1 ng DNA template. Using 0.5 ng DNA template resulted in increased allele recovery and improved intra- and inter-locus peak balance.


Asunto(s)
Genotipo , Cambios Post Mortem , Alelos , Cromosomas Humanos Y , ADN/genética , Antropología Forense , Humanos , Repeticiones de Microsatélite/genética
7.
FEMS Microbiol Lett ; 355(2): 108-15, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24831464

RESUMEN

Rhynchophorus ferrugineus is considered the worst pest of palm species, and few natural enemies are reported for this parasite in its area of origin. Here, we report the first recovery of the entomopathogenic fungus Metarhizium pingshaense associated with R. ferrugineus from Vietnam. The morphological, biochemical, and toxicological features of this strain were studied and compared with those of another Metarhizium strain associated with this weevil in Sicily (Italy), an area of recent introduction. The potential use of these fungi as biocontrol agents was tested against adult insects in laboratory trials and a similar mortality rate was found. Both strains were able to produce toxins and cuticle-degrading proteases, but they showed dissimilar enzymatic and toxicological profiles, suggesting a different virulence activity.


Asunto(s)
Metarhizium/aislamiento & purificación , Gorgojos/microbiología , Animales , Agentes de Control Biológico , ADN de Hongos/genética , Depsipéptidos/aislamiento & purificación , Italia , Masculino , Metarhizium/química , Metarhizium/citología , Microscopía Electrónica de Rastreo , Micotoxinas/aislamiento & purificación , Péptido Hidrolasas/metabolismo , Vietnam
8.
Chir Main ; 27(1): 26-30, 2008 Feb.
Artículo en Francés | MEDLINE | ID: mdl-18321751

RESUMEN

PURPOSE OF THE STUDY: We reviewed, at a mean follow-up of 8.2 years, clinical and radiographic results after 93 Bristow-Latarjet procedures for anterior instability of the shoulder. MATERIAL AND METHODS: There were 84 men and nine female. The average age was 23 years at the time of operative intervention. Forty-four shoulders were on the dominant side. Eighty patients practiced sports activities, with 74 patients a risk sport. Seventy-seven patients have had five or more recurrent of dislocation of the shoulder. The operations were performed by a senior surgeon. Evaluation was done by a clinician, who did not perform the operation. Clinical outcome was assessed with the Duplay score, and the satisfaction of the patients. Radiographic evaluation was done using the standard radiography of the shoulder. RESULTS: According to the Duplay scoring system, we have had 30.1% of excellent results, 43% of good results, 16.1% of fair results, and 10.8% of poor results. The mean Duplay score was 84.7 points with 19 points for the return in sports, 23 points for the stability, 21 points for the pain, and 22 points for the movement. The loss of rotation was less than 13 degrees (mean). Among the patients, 57.4% returned to their former sports activities at the same level, with 59.8% a risk sports. Five patients reported redislocation and eleven patients reported apprehension. The patients were painless in 75.8%. Forty-four patients were very satisfied or satisfied at follow-up. At review, there were radiological degenerative changes in nine shoulders: six in Samilson grade I, one grade II, and two grade III. There was no radiological evidence of loosing, migration or fracture of the coracoid screws, and no nonunion. We have had six cases of resorption of the coracoid tip. DISCUSSION: We are aware of the limitation of the study. It is a retrospective study and there is no control group. However, we believe that, in regard of our result, the Bristow-Latarjet procedure for anterior glenohumeral instability is safe and effective with good objective and subjective result, and a high degree of patient satisfaction. Radiological findings do not always correlate with the functional outcome and patient satisfaction. CONCLUSION: Although it is a non-anatomical repair, the Bristow-Latarjet procedure provides desirable functional results.


Asunto(s)
Inestabilidad de la Articulación/cirugía , Procedimientos Ortopédicos , Articulación del Hombro , Adulto , Interpretación Estadística de Datos , Femenino , Estudios de Seguimiento , Humanos , Inestabilidad de la Articulación/diagnóstico , Inestabilidad de la Articulación/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Satisfacción del Paciente , Radiografía , Recuperación de la Función , Estudios Retrospectivos , Luxación del Hombro/complicaciones , Articulación del Hombro/fisiología , Dolor de Hombro/etiología , Deportes , Factores de Tiempo , Resultado del Tratamiento
9.
Insect Mol Biol ; 16(5): 563-72, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17725799

RESUMEN

Caspases are cysteinyl-aspartate-specific proteases known for their role in apoptosis. Here, we describe the characterization of Aedes Dronc, a novel caspase in the yellow fever mosquito, Aedes aegypti. Aedes Dronc is predicted to contain an N-terminal caspase recruitment domain and is a homologue of Drosophila Dronc and human caspase-9. An increase in transcripts and caspase activity coincides with developmental changes in the mosquito, suggesting that Aedes Dronc plays a role in developmental apoptosis. Exposure of third instar larvae to ecdysone resulted in a significant increase in both transcript levels and caspase activity. We present here a functional characterization of the first caspase recruitment domain-containing caspase in mosquitoes, and will initiate studies on the role of apoptosis in the innate immune response of vectors.


Asunto(s)
Aedes/enzimología , Caspasas/metabolismo , Ecdisona/metabolismo , Estadios del Ciclo de Vida/fisiología , Aedes/genética , Aedes/crecimiento & desarrollo , Secuencia de Aminoácidos , Animales , Caspasas/genética , Femenino , Expresión Génica , Regulación del Desarrollo de la Expresión Génica , Humanos , Insectos Vectores/enzimología , Insectos Vectores/genética , Insectos Vectores/crecimiento & desarrollo , Datos de Secuencia Molecular , Fiebre Amarilla/transmisión
10.
Genomics ; 75(1-3): 77-83, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11472070

RESUMEN

Proteins governing cell death form the basis of many normal processes and contribute to the pathogenesis of many diseases when dysregulated. Here we report the cloning of a novel human CED-4-like gene, CLAN, and several of its alternatively spliced isoforms. These caspase-associated recruitment domain (CARD)-containing proteins are expressed at varying degrees in normal human tissues and may contribute to a number of intracellular processes including apoptosis, cytokine processing, and NF-kappa B activation. The CARD of the CLAN proteins binds a number of other CARD-containing proteins including caspase-1, BCL10, NOD2, and NAC. Once their physiologic functions are uncovered, CLAN proteins may prove to be valuable therapeutic targets.


Asunto(s)
Proteínas de Caenorhabditis elegans , Proteínas de Unión al Calcio/biosíntesis , Proteínas de Unión al Calcio/genética , Proteínas del Helminto/genética , Secuencia de Aminoácidos , Apoptosis , Proteínas Reguladoras de la Apoptosis , Proteínas Adaptadoras de Señalización CARD , Proteínas de Unión al Calcio/química , Caspasas/química , Cromosomas Humanos Par 2 , Clonación Molecular , ADN Complementario/metabolismo , Electroforesis en Gel de Poliacrilamida , Humanos , Modelos Genéticos , Datos de Secuencia Molecular , FN-kappa B/metabolismo , Hibridación de Ácido Nucleico , Plásmidos/metabolismo , Pruebas de Precipitina , Isoformas de Proteínas , Estructura Terciaria de Proteína , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Homología de Secuencia de Aminoácido , Distribución Tisular
11.
J Biol Chem ; 276(34): 32220-9, 2001 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-11408476

RESUMEN

Caspase-associated recruitment domains (CARDs) are protein interaction domains that participate in activation or suppression of CARD-carrying members of the caspase family of apoptosis-inducing proteases. A novel CARD-containing protein was identified that is overexpressed in some types of cancer and that binds and suppresses activation of procaspase-9, which we term TUCAN (tumor-up-regulated CARD-containing antagonist of caspase nine). The CARD domain of TUCAN selectively binds itself and procaspase-9. TUCAN interferes with binding of Apaf1 to procaspase-9 and suppresses caspase activation induced by the Apaf1 activator, cytochrome c. Overexpression of TUCAN in cells by stable or transient transfection inhibits apoptosis and caspase activation induced by Apaf1/caspase-9-dependent stimuli, including Bax, VP16, and staurosporine, but not by Apaf1/caspase-9-independent stimuli, Fas and granzyme B. High levels of endogenous TUCAN protein were detected in several tumor cell lines and in colon cancer specimens, correlating with shorter patient survival. Thus, TUCAN represents a new member of the CARD family that selectively suppresses apoptosis induced via the mitochondrial pathway for caspase activation.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales , Apoptosis , Proteínas de Neoplasias/metabolismo , Secuencia de Aminoácidos , Factor Apoptótico 1 Activador de Proteasas , Secuencia de Bases , Proteínas Adaptadoras de Señalización CARD , Caspasa 9 , Inhibidores de Caspasas , Caspasas/metabolismo , Cartilla de ADN , Activación Enzimática , Precursores Enzimáticos/antagonistas & inhibidores , Precursores Enzimáticos/metabolismo , Humanos , Inmunohistoquímica , Células Jurkat , Modelos Moleculares , Datos de Secuencia Molecular , Proteínas de Neoplasias/química , Proteínas de Neoplasias/genética , Neoplasias/enzimología , Unión Proteica , Conformación Proteica , Proteínas/química , Homología de Secuencia de Aminoácido
12.
Trends Biochem Sci ; 26(2): 85-7, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11166558

RESUMEN

A new protein domain was found in several proteins involved in apoptosis, inflammation, cancer and immune responses. Its location within these proteins and predicted fold suggests that it functions as a protein-protein interaction domain, possibly uniting different signaling pathways.


Asunto(s)
Apoptosis , Enfermedades Autoinmunes/metabolismo , Neoplasias/metabolismo , Secuencia de Aminoácidos , Animales , Proteínas del Citoesqueleto , Bases de Datos Factuales , Humanos , Inflamación/metabolismo , Datos de Secuencia Molecular , Unión Proteica , Pliegue de Proteína , Estructura Terciaria de Proteína , Proteínas/química , Pirina , Homología de Secuencia de Aminoácido , Transducción de Señal
13.
J Biol Chem ; 276(12): 9239-45, 2001 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-11113115

RESUMEN

Apaf1/CED4 family members play central roles in apoptosis regulation as activators of caspase family cell death proteases. These proteins contain a nucleotide-binding (NB) self-oligomerization domain and a caspase recruitment domain (CARD). A novel human protein was identified, NAC, that contains an NB domain and CARD. The CARD of NAC interacts selectively with the CARD domain of Apaf1, a caspase-activating protein that couples mitochondria-released cytochrome c (cyt-c) to activation of cytosolic caspases. Cyt-c-mediated activation of caspases in cytosolic extracts and in cells is enhanced by overexpressing NAC and inhibited by reducing NAC using antisense/DNAzymes. Furthermore, association of NAC with Apaf1 is cyt c-inducible, resulting in a mega-complex (>1 MDa) containing both NAC and Apaf1 and correlating with enhanced recruitment and proteolytic processing of pro-caspase-9. NAC also collaborates with Apaf1 in inducing caspase activation and apoptosis in intact cells, whereas fragments of NAC representing only the CARD or NB domain suppress Apaf1-dependent apoptosis induction. NAC expression in vivo is associated with terminal differentiation of short lived cells in epithelia and some other tissues. The ability of NAC to enhance Apaf1-apoptosome function reveals a novel paradigm for apoptosis regulation.


Asunto(s)
Apoptosis , Caspasas/metabolismo , Grupo Citocromo c/metabolismo , Elementos de Facilitación Genéticos , Proteínas/genética , Secuencia de Aminoácidos , Factor Apoptótico 1 Activador de Proteasas , Secuencia de Bases , Línea Celular , Cartilla de ADN , Activación Enzimática , Humanos , Inmunohistoquímica , Datos de Secuencia Molecular , Homología de Secuencia de Aminoácido
14.
Arq Neuropsiquiatr ; 58(1): 146-9, 2000 Mar.
Artículo en Portugués | MEDLINE | ID: mdl-10770880

RESUMEN

We report on four cases of primary orthostatic tremor. The purpose of this study is the rarity of this type of tremor and the differential diagnosis with other tremors. The electrophysiological study showed a 15-20 Hz tremor frequency in our cases. There are clinical, electrophysiological and therapeutic differences of primary orthostatic tremor in report to other tremors of legs, according to the literature and characteristics of our cases.


Asunto(s)
Pierna , Temblor/diagnóstico , Adulto , Ansiolíticos/uso terapéutico , Anticonvulsivantes/uso terapéutico , Brazo , Clonazepam/uso terapéutico , Depresión/tratamiento farmacológico , Diagnóstico Diferencial , Electromiografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Postura , Primidona/uso terapéutico , Propranolol/uso terapéutico , Temblor/tratamiento farmacológico
15.
Bioinformatics ; 16(12): 1105-10, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11159329

RESUMEN

MOTIVATION: Two proteins can have a similar 3-dimensional structure and biological function, but have sequences sufficiently different that traditional protein sequence comparison algorithms do not identify their relationship. The desire to identify such relations has led to the development of more sensitive sequence alignment strategies. One such strategy is the Intermediate Sequence Search (ISS), which connects two proteins through one or more intermediate sequences. In its brute-force implementation, ISS is a strategy that repetitively uses the results of the previous query as new search seeds, making it time-consuming and difficult to analyze. RESULTS: Saturated BLAST is a package that performs ISS in an efficient and automated manner. It was developed using Perl and Perl/Tk and implemented on the LINUX operating system. Starting with a protein sequence, Saturated BLAST runs a BLAST search and identifies representative sequences for the next generation of searches. The procedure is run until convergence or until some predefined criteria are met. Saturated BLAST has a friendly graphic user interface, a built-in BLAST result parser, several multiple alignment tools, clustering algorithms and various filters for the elimination of false positives, thereby providing an easy way to edit, visualize, analyze, monitor and control the search. Besides detecting remote homologies, Saturated BLAST can be used to maintain protein family databases and to search for new genes in genomic databases.


Asunto(s)
Alineación de Secuencia/estadística & datos numéricos , Programas Informáticos , Algoritmos , Secuencia de Aminoácidos , Biología Computacional , Gráficos por Computador , Sistemas de Administración de Bases de Datos , Bases de Datos Factuales , Datos de Secuencia Molecular , Proteínas/genética , Diseño de Software , Interfaz Usuario-Computador
16.
Protein Sci ; 8(10): 2098-109, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10548056

RESUMEN

The ETS family members display specific DNA binding site preferences. As an example, PU.1 and ETS-1 recognize different DNA sequences with a core element centered over 5'-GGAA-3' and 5'-GGAA/T-3', respectively. To understand the molecular basis of this recognition, we carried out site-directed mutagenesis experiments followed by DNA binding studies that use electrophoretic mobility shift assay (EMSA) and surface plasmon resonance methods. EMSA experiments identified amino acid changes A231S and/or N236Y as being important for PU.1 recognition of both 5'-GGAA-3' and 5'-GGAT-3' containing oligonucleotides. To confirm these data and obtain accurate binding parameters, we performed kinetic studies using surface plasmon resonance on these mutants. The N236Y substitution revealed a weak protein-DNA interaction with the 5'-GGAA-3' containing oligonucleotide caused by a faster release of the protein from the DNA (k(off) tenfold higher than the wild-type protein). With the double mutant A231S-N236Y, we obtained an increase in binding affinity and stability toward both 5'-GGAA-3' and 5'-GGAT-3' containing oligonucleotides. We propose that substitution of alanine for serine introduces an oxygen atom that can accept hydrogen and interact with potential water molecules or other atoms to make an energetically favorable hydrogen bond with both 5'-GGAA-3' and 5'-GGAT-3' oligonucleotides. The free energy of dissociation for the double mutant A231S-N236Y with 5'-GGAA-3' (delta deltaG((A231S-N236Y) - (N236Y)) = -1.2 kcal mol confirm the stabilizing effect of this mutant in the protein-DNA complex formation. We conclude that N236Y mutation relaxes the specificity toward 5'-GGAA-3' and 5'-GGAT-3' sequences, while A231S mutation modulates the degree of specificity toward 5'-GGAA-3' and 5'GGAT-3' sequences. This study explains why wild-type PU.1 does not recognize 5'-GGAT-3' sequences and in addition broadens our understanding of 5'-GGAA/T-3' recognition by ETS protein family members.


Asunto(s)
ADN/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Transactivadores/metabolismo , Secuencia de Aminoácidos , Secuencia de Bases , Cartilla de ADN , Cinética , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Proteínas Proto-Oncogénicas/química , Proteínas Proto-Oncogénicas/genética , Resonancia por Plasmón de Superficie , Transactivadores/química , Transactivadores/genética
17.
Blood ; 92(5): 1576-85, 1998 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-9716585

RESUMEN

PU.1 is an ets family transcription factor that is expressed specifically in hematopoietic lineages. Through gene disruption studies in mice we have previously shown that the expression of PU.1 is not essential for early myeloid lineage or neutrophil commitment, but is essential for monocyte/macrophage development. We have also shown that PU.1-null (deficient) neutrophils have neutrophil morphology and express neutrophil-specific markers such as Gr-1 and chloroacetate esterase both in vivo and in vitro. We now demonstrate that although PU.1-null mice develop neutrophils, these cells fail to terminally differentiate as shown by the absence of messages for neutrophil secondary granule components and the absence or deficiency of cellular responses to stimuli that normally invoke neutrophil function. Specifically, PU.1-deficient neutrophils fail to respond to selected chemokines, do not generate superoxide ions, and are ineffective at bacterial uptake and killing. The failure to produce superoxide could, in part, be explained by the absence of the gp91 subunit of nicotinamide adenine dinucleotide phosphate oxidase, as shown by our inability to detect messages for the gp91(phox) gene. Incomplete maturation of PU.1-deficient neutrophils is cell autonomous and persists in cultured PU.1-deficient cells. Our results indicate that PU.1 is not necessary for neutrophil lineage commitment but is essential for normal development, maturation, and function of neutrophils.


Asunto(s)
Diferenciación Celular , Proteínas de Unión al ADN/metabolismo , Neutrófilos/citología , Neutrófilos/fisiología , Transactivadores/deficiencia , Transactivadores/metabolismo , Animales , Células Cultivadas , Quimiotaxis de Leucocito , Gránulos Citoplasmáticos/genética , Proteínas de Unión al ADN/fisiología , Factor Estimulante de Colonias de Granulocitos/farmacología , Factor Estimulante de Colonias de Granulocitos y Macrófagos/farmacología , Factores Reguladores del Interferón , Interleucina-8/farmacología , Factor Estimulante de Colonias de Macrófagos/farmacología , Ratones , N-Formilmetionina Leucil-Fenilalanina/farmacología , NADPH Oxidasas/genética , Activación Neutrófila , Fagocitosis , Fenotipo , ARN Mensajero/análisis , Superóxidos/metabolismo , Acetato de Tetradecanoilforbol/farmacología , Transactivadores/fisiología
18.
Protein Sci ; 5(9): 1934-8, 1996 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8880920

RESUMEN

Fibronectin is a large cell adhesion molecule that is composed of several functional domains. The cell-binding domain that binds to cell surface integrins consists of repeated homologous type III modules. In this study, recombinant fragments from the cell-binding domain of human fibronectin that participate in a newly characterized fibronectin-fibronectin interaction with FNIII1 were crystallized. In each case, the crystals had more than one fibronectin fragment in the asymmetric unit. Crystals of FNIII10-11 grew in the space group C2 with a = 117.1 A, b = 38.6 A, c = 80.6 A, beta = 97.2 degrees, and two molecules in the asymmetric unit. These crystals diffracted to 2.5 A resolution. Fragment FNIII8-11 and a shorter fragment, FNIII8-10, crystallized in hexagonal space groups with large unit cells and two to four molecules per asymmetric unit. Even very large crystals of these fragments did not diffract beyond 4 A. The crystal packing for this collection of fibronectin fragments suggests conformational flexibility between linked type III modules. The functional relevance of this flexibility for elongated versus compact models of the cell-binding domain of fibronectin is discussed.


Asunto(s)
Fibronectinas/química , Conformación Proteica , Sulfato de Amonio , Sitios de Unión , Precipitación Química , Cristalización , Humanos , Concentración de Iones de Hidrógeno , Integrinas/metabolismo , Sulfato de Magnesio , Fragmentos de Péptidos/química , Polietilenglicoles , Proteínas Recombinantes/química , Difracción de Rayos X
19.
J Biol Chem ; 271(38): 23329-37, 1996 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-8798534

RESUMEN

Transcription factors belonging to the ets family regulate gene expression and share a conserved ETS DNA-binding domain that binds to the core sequence 5'-(C/A)GGA(A/T)-3'. The domain is similar to alpha+beta ("winged") helix-turn-helix DNA-binding proteins. The crystal structure of the PU.1 ETS domain complexed to a 16-base pair oligonucleotide revealed a pattern for DNA recognition from a novel loop-helix-loop architecture (Kodandapani, R., Pio, F., Ni. C.-Z., Piccialli, G., Klemsz, M., McKercher, S., Maki, R. A., and Ely, K. R. (1996) Nature 380, 456-460). Correlation of this model with mutational analyses and chemical shift data on other ets proteins confirms this complex as a paradigm for ets DNA recognition. The second helix in the helix-turn-helix motif lies deep in the major groove with specific contacts with bases in both strands in the core sequence made by conserved residues in alpha3. On either side of this helix, two loops contact the phosphate backbone. The DNA is bent (8 degrees) but uniformly curved without distinct kinks. ETS domains bind DNA as a monomer yet make extensive DNA contacts over 30 A. DNA bending likely results from phosphate neutralization of the phosphate backbone in the minor groove by both loops in the loop-helix-loop motif. Contacts from these loops stabilize DNA bending and may mediate specific base interactions by inducing a bend toward the protein.


Asunto(s)
Proteínas de Unión al ADN/química , ADN/química , Secuencias Hélice-Giro-Hélice , Proteínas Proto-Oncogénicas/química , Secuencia de Aminoácidos , Animales , Cristalografía por Rayos X , Análisis Mutacional de ADN , Ratones , Modelos Moleculares , Datos de Secuencia Molecular , Unión Proteica , Proteína Proto-Oncogénica c-fli-1 , Proteínas Proto-Oncogénicas c-ets , Homología de Secuencia de Aminoácido , Transactivadores/química , Factores de Transcripción/química
20.
Nature ; 380(6573): 456-60, 1996 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-8602247

RESUMEN

The Ets family of transcription factors, of which there are now about 35 members regulate gene expression during growth and development. They share a conserved domain of around 85 amino acids which binds as a monomer to the DNA sequence 5'-C/AGGAA/T-3'. We have determined the crystal structure of an ETS domain complexed with DNA, at 2.3-A resolution. The domain is similar to alpha + beta (winged) 'helix-turn-helix' proteins and interacts with a ten-base-pair region of duplex DNA which takes up a uniform curve of 8 degrees. The domain contacts the DNA by a novel loop-helix-loop architecture. Four of amino acids that directly interact with the DNA are highly conserved: two arginines from the recognition helix lying in the major groove, one lysine from the 'wing' that binds upstream of the core GGAA sequence, and another lysine, from the 'turn' of the 'helix-turn-helix' motif, which binds downstream and on the opposite strand.


Asunto(s)
Proteínas de Unión al ADN/química , ADN/química , Secuencias Hélice-Giro-Hélice , Secuencia de Aminoácidos , Animales , Cristalografía por Rayos X , ADN/metabolismo , Proteínas de Unión al ADN/metabolismo , Humanos , Modelos Moleculares , Datos de Secuencia Molecular , Conformación de Ácido Nucleico , Unión Proteica , Conformación Proteica , Proteínas Oncogénicas de Retroviridae , Homología de Secuencia de Aminoácido
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