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1.
Front Psychol ; 13: 965926, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36211841

RESUMEN

This study aimed to develop cross-domain deep learning courses of artificial intelligence in vocational senior high schools and explore its impact on students' learning effects. It initially adopted a literature review to develop a cross-domain SPOC-AIoT Course with SPOC (small private online courses) and the Double Diamond 4D model in vocational senior high schools. Afterward, it adopted participatory action research (PAR) and a questionnaire survey and conducted analyses on the various aspects of the technology acceptance model by SmartPLS. Further, this study explored the impact on the effects of deep learning and knowledge-ability learning of artificial intelligence after 16 weeks of course teaching among 36 Grade I students from the electrical and electronic group of a vocational senior high school. This study revealed that (1) the four stages of the SPOC-AIoT Teaching Mode of the Double Diamond 4D model may effectively guide students to learn AIoT knowledge and skills. (2) Based on the technology acceptance model, the analysis of learning and participation in SmartPLS indicated that this model conformed to the academic fitness requirements of the overall model. (3) After learning with the SPOC-AIoT Teaching Mode, the learning effects of students in AIoT have been significantly improved to a positive aspect. Finally, some suggestions were put forward to promote the development of the SPOC-AIoT Teaching Mode Course in the future.

2.
Front Psychol ; 13: 1011551, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36304872

RESUMEN

This study explored the relationship and influence of college students' participation in water leisure sports, as well as the technology acceptance model (TAM). With the rapid development of the economy, the government is promoting various water leisure sports centered on the concept and policy of a maritime- and ocean-based nation. Based on the TAM, this study investigated the relationships among its ease of use, usefulness, water leisure involvement, benefits, barriers, and intentions to participate in water activities in connection with college students participating in water leisure sports. A total of 420 college students who participated in water leisure activities were sampled. There were 370 valid questionnaires, and the recovery rate of valid questionnaires was 82.2%. The data were analyzed by the structural equation modeling of the partial least squares method (PLS-SEM). The results show that the ease of use of water facilities had a positive effect on the usefulness, involvement, and participation in water activities; the usefulness of water facilities had a positive and significant impact on the intention to participate in water activities; water leisure involvement had a positive and significant impact on the benefits and the intention to participate in water activities; the intention to participate in water activities had a positive and significant impact on the benefits of water leisure activities. Furthermore, the study found that the intention to participate in water activities had a mediating effect between water leisure involvement and water leisure benefits; water leisure involvement had a mediating effect between the ease of use of water facilities and the intention to participate in water activities; the usefulness of water facilities had a mediating effect between the ease of use of water facilities and the intention to participate in water activities. In addition, the interaction between water leisure involvement and water leisure constraints had an interfering effect on water leisure benefits. Accordingly, recommendations for promotion and implementation are provided. Based on the TAM, the study provided suggestions for implementing water leisure sports to promote college students' participation behavior in water leisure sports.

3.
Genes Dev ; 29(4): 440-50, 2015 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-25691470

RESUMEN

The orphan nuclear receptor TLX regulates neural stem cell self-renewal in the adult brain and functions primarily as a transcription repressor through recruitment of Atrophin corepressors, which bind to TLX via a conserved peptide motif termed the Atro box. Here we report crystal structures of the human and insect TLX ligand-binding domain in complex with Atro box peptides. In these structures, TLX adopts an autorepressed conformation in which its helix H12 occupies the coactivator-binding groove. Unexpectedly, H12 in this autorepressed conformation forms a novel binding pocket with residues from helix H3 that accommodates a short helix formed by the conserved ALXXLXXY motif of the Atro box. Mutations that weaken the TLX-Atrophin interaction compromise the repressive activity of TLX, demonstrating that this interaction is required for Atrophin to confer repressor activity to TLX. Moreover, the autorepressed conformation is conserved in the repressor class of orphan nuclear receptors, and mutations of corresponding residues in other members of this class of receptors diminish their repressor activities. Together, our results establish the functional conservation of the autorepressed conformation and define a key sequence motif in the Atro box that is essential for TLX-mediated repression.


Asunto(s)
Drosophila melanogaster/química , Modelos Moleculares , Receptores Nucleares Huérfanos/química , Receptores Citoplasmáticos y Nucleares/química , Animales , Cristalización , Proteínas de Drosophila/química , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Células HEK293 , Humanos , Receptores Nucleares Huérfanos/metabolismo , Receptores Citoplasmáticos y Nucleares/metabolismo
4.
Biol Open ; 1(3): 182-96, 2012 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-23213409

RESUMEN

SMRTER (SMRT-related and ecdysone receptor interacting factor) is the Drosophila homologue of the vertebrate proteins SMRT and N-CoR, and forms with them a well-conserved family of transcriptional corepressors. Molecular characterization of SMRT-family proteins in cultured cells has implicated them in a wide range of transcriptional regulatory pathways. However, little is currently known about how this conserved class of transcriptional corepressors regulates the development of particular tissues via specific pathways. In this study, through our characterization of multiple Smrter (Smr) mutant lines, mosaic analysis of a loss-of-function Smr allele, and studies of two independent Smr RNAi fly lines, we report that SMRTER is required for the development of both ovarian follicle cells and the wing. In these two tissues, SMRTER inhibits not only the ecdysone pathway, but also the Notch pathway. We differentiate SMRTER's influence on these two signaling pathways by showing that SMRTER inhibits the Notch pathway, but not the ecdysone pathway, in a spatiotemporally restricted manner. We further confirm the likely involvement of SMRTER in the Notch pathway by demonstrating a direct interaction between SMRTER and Suppressor of Hairless [Su(H)], a DNA-binding transcription factor pivotal in the Notch pathway, and the colocalization of both proteins at many chromosomal regions in salivary glands. Based on our results, we propose that SMRTER regulates the Notch pathway through its association with Su(H), and that overcoming a SMRTER-mediated transcriptional repression barrier may represent a key mechanism used by the Notch pathway to control the precise timing of events and the formation of sharp boundaries between cells in multiple tissues during development.

5.
EMBO Rep ; 12(5): 428-35, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21475249

RESUMEN

Ataxin-1 (ATXN1), a causative factor for spinocerebellar ataxia type 1 (SCA1), and the related Brother of ATXN1 (BOAT1) are human proteins involved in transcriptional repression. So far, little is known about which transcriptional pathways mediate the effects of ATXN1 and BOAT1. From our analyses of the properties of BOAT1 in Drosophila and of both proteins in mammalian cells, we report here that BOAT1 and ATXN1 are components of the Notch signalling pathway. In Drosophila, BOAT1 compromises the activities of Notch. In mammalian cells, both ATXN1 and BOAT1 bind to the promoter region of Hey1 and inhibit the transcriptional output of Notch through direct interactions with CBF1, a transcription factor that is crucial for the Notch pathway. Our results suggest that, in addition to their involvement in SCA1, ATXN1 and BOAT1 might participate in several Notch-controlled developmental and pathological processes.


Asunto(s)
Proteínas del Tejido Nervioso/metabolismo , Proteínas Nucleares/metabolismo , Receptores Notch/metabolismo , Proteínas Represoras/metabolismo , Transducción de Señal/fisiología , Animales , Ataxina-1 , Ataxinas , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Proteínas de Ciclo Celular/metabolismo , Línea Celular , Inmunoprecipitación de Cromatina , Cartilla de ADN/genética , Drosophila , Proteínas de Drosophila/metabolismo , Humanos , Proteína de Unión a la Señal Recombinante J de las Inmunoglobulinas/metabolismo , Inmunoprecipitación , Ratones , Microscopía Fluorescente , Plásmidos/genética , Reacción en Cadena de la Polimerasa , ARN Interferente Pequeño/genética , Transducción de Señal/genética , Técnicas del Sistema de Dos Híbridos
6.
Dev Neurosci ; 33(1): 1-13, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21124006

RESUMEN

Drosophila Tailless(Tll) and its vertebrate homologue Tlx are conserved orphan nuclear receptors specifically expressed in the eye and the forebrain. Tll and Tlx act primarily as transcriptional repressors through their interactions with transcriptional corepressors, Atrophin family proteins, and histone-tail/chromatin-modifying factors such as lysine-specific histone demethylase 1 and histone deacetylases. The functional importance of Tll and Tlx is made apparent by the recent discovery that they are expressed in neural stem cells (NSCs) and are required for self-renewal of these cells in both Drosophila and the mouse. This review provides a snapshot of current knowledge about Tll and Tlx and their transcriptional network, which maintains NSCs in developing and adult animals.


Asunto(s)
Proteínas de Drosophila/metabolismo , Drosophila melanogaster/fisiología , Células-Madre Neurales/fisiología , Receptores Citoplasmáticos y Nucleares/metabolismo , Proteínas Represoras/metabolismo , Transcripción Genética , Secuencia de Aminoácidos , Animales , Sistema Nervioso Central/anatomía & histología , Sistema Nervioso Central/embriología , Sistema Nervioso Central/crecimiento & desarrollo , Proteínas de Drosophila/clasificación , Proteínas de Drosophila/genética , Drosophila melanogaster/anatomía & histología , Drosophila melanogaster/embriología , Ratones , Ratones Noqueados , Datos de Secuencia Molecular , Células-Madre Neurales/citología , Filogenia , Receptores Citoplasmáticos y Nucleares/clasificación , Receptores Citoplasmáticos y Nucleares/genética , Proteínas Represoras/clasificación , Proteínas Represoras/genética , Alineación de Secuencia , Homología de Secuencia de Aminoácido
7.
Ophthalmologica ; 223(6): 376-82, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19602909

RESUMEN

BACKGROUND: Severe or recurrent blepharoptosis remains a great challenge to most plastic surgeons. A variety of techniques have been developed according to the function of the levator palpebrae superioris and frontalis muscles. In this study, the frontalis-orbicularis oculi (FOO) muscle flap is designed as an entity to treat severe or recurrent blepharoptosis with satisfactory results. METHODS: Between January 1997 and July 2007, FOO muscle flap shortening was applied to correct severe or recurrent blepharoptosis in 29 patients (38 eyelids), aged from 3 to 77 years. There were 11 males and 18 females, with bilateral ptosis in 9 patients. The follow-up period ranged from 10 to 52 months. RESULTS: Twenty-four patients (82%) had good results, with the degree of ptosis less than 2 mm. The remaining 5 patients had fair results, and received readjustment in 2 cases. CONCLUSION: In our study, fresh cadaver dissection revealed that the frontalis muscle is connected and interdigitated very closely with the orbicularis oculi muscle. Based on the anatomic study and literature review, we suggest that the FOO muscle flap shortening is a good alternative to treat severe or recurrent blepharoptosis.


Asunto(s)
Blefaroptosis/cirugía , Párpados/cirugía , Músculos Faciales/cirugía , Colgajos Quirúrgicos , Adolescente , Adulto , Anciano , Blefaroptosis/patología , Cadáver , Niño , Preescolar , Disección , Párpados/anatomía & histología , Músculos Faciales/anatomía & histología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/prevención & control , Prevención Secundaria , Índice de Severidad de la Enfermedad , Adulto Joven
8.
Hum Mutat ; 30(3): 342-51, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19006237

RESUMEN

NR2E3, a photoreceptor-specific nuclear receptor (PNR), represses cone-specific genes and activates several rod-specific genes. In humans, mutations in NR2E3 have been associated with the recessively-inherited enhanced short-wavelength sensitive S-cone syndrome (ESCS) and, recently, with autosomal dominant (ad) retinitis pigmentosa (RP) (adRP). In the present work, we describe two additional families affected by adRP that carry a heterozygous c.166G>A (p.G56R) mutation in the NR2E3 gene. Functional analysis determined the dominant negative activity of the p.G56R mutant protein as the molecular mechanism of adRP. Interestingly, in one pedigree, the most common causal variant for ESCS (p.R311Q) cosegregated with the adRP-linked p.G56R mutation, and the compound heterozygotes exhibited an ESCS-like phenotype, which in 1 of the 2 cases was strikingly "milder" than the patients carrying the p.G56R mutation alone. Impaired repression of cone-specific genes by the corepressors atrophin-1 (dentatorubral-pallidoluysian atrophy [DRPLA] gene product) and atrophin-2 (arginine-glutamic acid dipeptide repeat [RERE] protein) appeared to be a molecular mechanism mediating the beneficial effect of the p.R311Q mutation. Finally, the functional dominance of the p.R311Q variant to the p.G56R mutation is discussed.


Asunto(s)
Mutación , Receptores Citoplasmáticos y Nucleares/genética , Degeneración Retiniana/genética , Factores de Transcripción/genética , Adolescente , Adulto , Anciano , Secuencia de Aminoácidos , Animales , Línea Celular , Ensayo de Cambio de Movilidad Electroforética , Salud de la Familia , Femenino , Genes Dominantes , Genes Recesivos , Genotipo , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Datos de Secuencia Molecular , Receptores Nucleares Huérfanos , Linaje , Unión Proteica , Receptores Citoplasmáticos y Nucleares/metabolismo , Degeneración Retiniana/patología , Retinitis Pigmentosa/genética , Retinitis Pigmentosa/patología , Homología de Secuencia de Aminoácido , Factores de Transcripción/metabolismo , Adulto Joven
9.
Nucl Recept Signal ; 6: e009, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-19043594

RESUMEN

The normal development and physiological functions of multicellular organisms are regulated by complex gene transcriptional networks that include myriad transcription factors, their associating coregulators, and multiple chromatin-modifying factors. Aberrant gene transcriptional regulation resulting from mutations among these elements often leads to developmental defects and diseases. This review article concentrates on the Atrophin family proteins, including vertebrate Atrophin-1 (ATN1), vertebrate arginine-glutamic acid dipeptide repeats protein (RERE), and Drosophila Atrophin (Atro), which we recently identified as nuclear receptor corepressors. Disruption of Atrophin-mediated pathways causes multiple developmental defects in mouse, zebrafish, and Drosophila, while an aberrant form of ATN1 and altered expression levels of RERE are associated with neurodegenerative disease and cancer in humans, respectively. We here provide an overview of current knowledge about these Atrophin proteins. We hope that this information on Atrophin proteins may help stimulate fresh ideas about how this newly identified class of nuclear receptor corepressors aids specific nuclear receptors and other transcriptional factors in regulating gene transcription, manifesting physiological effects, and causing diseases.


Asunto(s)
Proteínas Portadoras/metabolismo , Proteínas de Drosophila/metabolismo , Regulación de la Expresión Génica/fisiología , Proteínas del Tejido Nervioso/metabolismo , Receptores Citoplasmáticos y Nucleares/metabolismo , Proteínas Represoras/clasificación , Proteínas Represoras/metabolismo , Factores de Transcripción/metabolismo , Animales , Drosophila , Humanos
10.
EMBO Rep ; 9(6): 555-62, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18451879

RESUMEN

Atrophin family proteins, including the vertebrate arginine-glutamic acid dipeptide repeats protein (RERE) and Drosophila Atrophin (Atro), constitute a new class of nuclear receptor corepressors. Both RERE and Atro share the ELM2 (EGL-27 and MTA1 homology 2) and SANT (SWI3/ADA2/N-CoR/TFIII-B) domains, which are also present in other important transcriptional cofactors. Here, we report that the SANT domain in RERE binds to the histone methyltransferase G9a, and that both the ELM2 and SANT domains orchestrate molecular events that lead to a stable methylation of histone H3-lysine 9. We establish the physiological relevance of these interactions among Atrophin, G9a, and histone deacetylases 1 and 2 in Drosophila by showing that these proteins localize to overlapping chromosomal loci, and act together to suppress wing vein and melanotic-mass formation. This study not only shows a new function of the SANT domain and establishes its connection with the ELM2 domain, but also implies that a similar strategy is used by other ELM2-SANT proteins to repress gene transcription and to exert biological effects.


Asunto(s)
Proteínas de Drosophila/metabolismo , Histona Desacetilasas/metabolismo , N-Metiltransferasa de Histona-Lisina/metabolismo , Histonas/metabolismo , Lisina/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Proteínas Represoras/metabolismo , Animales , Línea Celular , Linaje de la Célula , Proteínas de Drosophila/genética , Drosophila melanogaster/anatomía & histología , Drosophila melanogaster/fisiología , Neoplasias de Cabeza y Cuello/metabolismo , Neoplasias de Cabeza y Cuello/patología , Histona Desacetilasa 1 , Histona Desacetilasa 2 , Histona Desacetilasas/genética , Histona Metiltransferasas , N-Metiltransferasa de Histona-Lisina/genética , Humanos , Masculino , Proteínas del Tejido Nervioso/genética , Unión Proteica , Proteína Metiltransferasas , Estructura Terciaria de Proteína , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Secuencias Repetitivas de Aminoácido , Proteínas Represoras/genética
11.
Acta Anaesthesiol Taiwan ; 45(2): 79-87, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17694683

RESUMEN

BACKGROUND: The Acute Pain Service Information Management System (APSIMS), as we coined, is the utilization of a portable computer to register the data of the patients who need acute pain management during anesthesiologist's ward round. Initially, the data of the daily acute pain assessment at the ward are recorded on a sheet of paper by the rounding anesthesiologist, which are subsequently entered into the hospital main frame computer by an anesthetic nurse. In order to save manpower in data entry, we planned to introduce the personal digital assistant (PDA) into acute pain assessment. The anesthesiologist can record a patient's data directly into the PDA device at the bedside. After acute pain assessment is finished, we can directly up load the data from the PDA to the hospital mainframe computer without the need of further manpower for doing data input. This study was to evaluate the use of PDA for acute pain assessment and compare the PDA-based method with that of the current paper-transcription method in work efficiency. METHODS: Two computer applications were developed: the APS Mobile Assistant and the Data Transformation Wizard (DTW). The APS Mobile Assistant is a PDA application running on a portable computer with Windows Mobile 2003 operation system. The anesthesiologist can use this application to perform APS assessment at the bedside. The Data Transformation Wizard is a PC application which can transfer data from the PDA device to the hospital mainframe computer, by which the data in the PDA system can be integrated into the hospital information system. The evaluation included the reckoning of the timings of two periods i.e. the time spent by the physician to perform acute pain assessment at the bedside and the time required for data management by the nurse. To compare the paper-transcription method with the PDA-based technique, the Student's t test was performed to assess the data of time of each category collected. A P value less than 0.05 was considered to be significant. RESULTS: When the time required for assessment of acute pain was determined, no statistically significant difference was observed between the use of the paper-transcription-based system and the PDA system (P = 0.258). In comparison the PDA system was clearly shown to facilitate faster management of data (Paper-transcription method: 1.57 +/- 0.08 min per patient compared with PDA-based method: 0.24 +/- 0.01 min per patient, P < 0.0001). CONCLUSIONS: Implementation of PDA device during APS assessment can provide the anesthesiologists with more time to acquire information during APS visits. Using the PDA technology in clinical settings can increase work efficiency. We can save manpower and are convinced that data collection is more complete with the use of a PDA system.


Asunto(s)
Anestesiología , Computadoras de Mano , Gestión de la Información , Manejo del Dolor , Enfermedad Aguda , Humanos , Dimensión del Dolor
12.
J Biol Chem ; 282(40): 29186-92, 2007 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-17646162

RESUMEN

Ataxin-1 is a neurodegenerative disorder protein whose mutant form causes spinocerebellar ataxia type-1 (SCA1). Evidence suggests that ataxin-1 may function as a transcription repressor. However, neither the importance of this putative transcriptional repression activity in neural cytotoxicity nor the transcriptional targets of ataxin-1 are known. Here we identify the MEF2-HDAC4 transcriptional complex involved in neuron survival as a target of ataxin-1. We show that ataxin-1 binds specifically to histone deacetylase-4 (HDAC4) and MEF2 and colocalizes with them in nuclear inclusion bodies. Significantly, these interactions are greatly reduced by the S776A mutation, which largely abrogates the cytotoxicity of ataxin-1. Supporting the importance of these interactions, we show that wild type ataxin-1 represses MEF2-dependent transcription, whereas the S776A mutant is less potent. Furthermore, overexpression of MEF2 can partially reverse cytotoxicity caused by ataxin-1. Our results identify the MEF2-HDAC4 complex as a target for ataxin-1 transcriptional repression activity and suggest a novel pathogenic mechanism whereby ataxin-1 sequesters and inhibits the neuronal survival factor MEF2.


Asunto(s)
Factores Reguladores Miogénicos/metabolismo , Proteínas del Tejido Nervioso/fisiología , Enfermedades Neurodegenerativas/metabolismo , Neuronas/metabolismo , Proteínas Nucleares/fisiología , Animales , Ataxina-1 , Ataxinas , Células COS , Cerebelo/citología , Chlorocebus aethiops , Histona Desacetilasas/metabolismo , Factores de Transcripción MEF2 , Ratones , Microscopía Fluorescente , Mutación , Proteínas del Tejido Nervioso/metabolismo , Proteínas Nucleares/metabolismo , Unión Proteica , Transporte de Proteínas , Transfección
13.
Genes Dev ; 20(5): 525-30, 2006 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-16481466

RESUMEN

Drosophila Tailless (Tll) is an orphan nuclear receptor involved in embryonic segmentation and neurogenesis. Although Tll exerts potent transcriptional repressive effects, the underlying molecular mechanisms have not been determined. Using the established regulation of knirps by tll as a paradigm, we report that repression of knirps by Tll involves Atrophin, which is related to vertebrate Atrophin-1 and Atrophin-2. Atrophin interacts with Tll physically and genetically, and both proteins localize to the same knirps promoter region. Because Atrophin proteins interact with additional nuclear receptors and Atrophin-2 selectively binds histone deacetylase 1/2 (HDAC1/2) through its ELM2 (EGL-27 and MTA1 homology 2)/SANT (SWI3/ADA2/N-CoR/TFIII-B) domains, our study establishes that Atrophin proteins represent a novel class of nuclear receptor corepressors.


Asunto(s)
Proteínas de Drosophila/metabolismo , Histona Desacetilasas/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Represoras/metabolismo , Factores de Transcripción/metabolismo , Alanina/metabolismo , Secuencias de Aminoácidos , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Animales , Línea Celular , Secuencia Conservada , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Drosophila/embriología , Drosophila/genética , Proteínas de Drosophila/química , Proteínas de Drosophila/genética , Embrión no Mamífero , Glutatión Transferasa/metabolismo , Histona Desacetilasas/genética , Humanos , Modelos Biológicos , Datos de Secuencia Molecular , Mutación , Proteínas Nucleares/genética , Co-Represor 1 de Receptor Nuclear , Regiones Promotoras Genéticas , Estructura Terciaria de Proteína , Proteínas Recombinantes de Fusión/metabolismo , Proteínas Represoras/química , Proteínas Represoras/genética , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Factores de Transcripción/química , Factores de Transcripción/genética , Técnicas del Sistema de Dos Híbridos , beta-Galactosidasa/análisis , beta-Galactosidasa/metabolismo
14.
EMBO J ; 24(18): 3339-51, 2005 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-16121196

RESUMEN

Ataxin-1 is a neurodegenerative disorder protein whose glutamine-repeat expanded form causes spinocerebellar ataxia type 1 (SCA1) in humans and exerts cytotoxicity in Drosophila and mouse. We report here that the cytotoxicity caused by ataxin-1 is modulated by association with a related protein, Brother of ataxin-1 (Boat). Boat and ataxin-1 share a conserved AXH (ataxin-1 and HMG-box protein 1) domain, which is essential for both proteins' interactions with the transcriptional corepressor SMRT and its Drosophila homolog, SMRTER. The Boat-ataxin-1 interaction is mediated through multiple regions in both proteins, including a newly identified NBA (N-terminal region of Boat and ataxin-1) domain. We investigated the physiological relevance of the Boat-ataxin-1 interaction in Drosophila and discovered that a mutant ataxin-1-mediated eye defect is suppressed by ataxin-1's association with Boat. Correspondingly, in transgenic SCA1 mouse, Boat expression is greatly reduced in Purkinje cells, the primary targets of SCA1. Our study thus establishes that Boat is an in vivo binding partner of ataxin-1 whose altered expression in Purkinje cells may contribute to their degeneration in SCA1 animals.


Asunto(s)
Mutación/genética , Proteínas del Tejido Nervioso/antagonistas & inhibidores , Proteínas del Tejido Nervioso/toxicidad , Proteínas Nucleares/antagonistas & inhibidores , Proteínas Nucleares/toxicidad , Proteínas Represoras/metabolismo , Secuencia de Aminoácidos , Animales , Ataxina-1 , Ataxinas , Encéfalo/metabolismo , Línea Celular , Núcleo Celular/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Ojo/metabolismo , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Histona Desacetilasas/metabolismo , Humanos , Ratones , Datos de Secuencia Molecular , Proteínas del Tejido Nervioso/química , Proteínas del Tejido Nervioso/metabolismo , Proteínas Nucleares/química , Proteínas Nucleares/metabolismo , Co-Represor 2 de Receptor Nuclear , Fenotipo , Unión Proteica , Estructura Terciaria de Proteína , Proteínas Represoras/química , Proteínas Represoras/genética , Alineación de Secuencia , Transcripción Genética/genética
15.
Artículo en Inglés | MEDLINE | ID: mdl-16019734

RESUMEN

Lacrimal outflow obstruction after severance of the duct is a common problem in facial trauma. Conventional treatments include external dacryocystorhinostomy, endoscopic-assisted dacryocystorhinostomy, conjunctivorhinostomy, and a Jones tube bypass. However, the disadvantages of these methods are that the procedures are complicated and there is a high rate of recurrence. From April 2000 to March 2003, seven patients with epiphora after facial trauma had their lacrimal ducts drained with epidural catheters. The V-M shape incision was used with an epidural catheter placed as a stent for six months. After removal of the tube, all patients recovered fully from the epiphora during the follow-up period, and there were no complications.


Asunto(s)
Cateterismo/instrumentación , Dacriocistorrinostomía , Traumatismos Faciales/complicaciones , Procedimientos de Cirugía Plástica/métodos , Adolescente , Adulto , Dacriocistorrinostomía/métodos , Drenaje/instrumentación , Drenaje/métodos , Diseño de Equipo , Seguridad de Equipos , Femenino , Estudios de Seguimiento , Humanos , Obstrucción del Conducto Lagrimal/etiología , Masculino , Persona de Mediana Edad , Procedimientos de Cirugía Plástica/instrumentación , Estudios Retrospectivos , Medición de Riesgo , Muestreo , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
16.
Macromol Biosci ; 4(10): 919-21, 2004 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-15490434

RESUMEN

A simple spectrophotometric method is proposed for determining deacetylation degrees (DD) of chitinous materials using phosphoric acid as the UV-transparent solvent system. Calibrating by the extinction coefficients (A(210)) of D-glucosamine and N-acetyl-D-glucosamine, DD values (24-88%) were computed numerically. The results correlated well (R(2) = 0.9805, n = 50) with those obtained by solid-state (13)C NMR. Comparison of the results obtained by the proposed UV method and solid-state (13)C NMR.


Asunto(s)
Quitina/química , Ácidos Fosfóricos/química , Espectrofotometría Ultravioleta/métodos , Acetilación , Quitosano/química , Espectroscopía de Resonancia Magnética , Modelos Teóricos , Programas Informáticos , Solventes , Factores de Tiempo , Rayos Ultravioleta
17.
Vitam Horm ; 68: 93-122, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15193452

RESUMEN

Nuclear receptors (NRs) compose one of the largest known families of eukaryotic transcription factors and, as such, serve as a paradigm for understanding the fundamental molecular mechanisms of eukaryotic transcriptional regulation. The packaging of eukaryotic genomic DNA into a higher ordered chromatin structure, which generally acts as a barrier to transcription by inhibiting transcription factor accessibility, has a major influence on the mechanisms by which NRs activate or repress gene expression. A major breakthrough in the field's understanding of these mechanisms comes from the recent identification of NR-associated coregulatory factors (i.e., coactivators and corepressors). Although several of these NR cofactors are involved in chromatin remodeling and facilitating the recruitment of the basal transcription machinery, the focus of this chapter is on NR coactivators and corepressors that act to covalently modify the amino-terminal tails of core histones. These modifications (acetylation, methylation, and phosphorylation) are thought to directly affect chromatin structure and?or serve as binding surfaces for other coregulatory proteins. This chapter presents the most current models for NR recruitment of histone-modifying enzymes and then summarizes their functional importance in NR-associated gene expression.


Asunto(s)
Histonas/metabolismo , Regiones Promotoras Genéticas/fisiología , Receptores Citoplasmáticos y Nucleares/fisiología , Transcripción Genética/fisiología , Transferasas/metabolismo , Acetilación , Sitios de Unión/fisiología , Cromatina/química , Humanos , Metilación , Proteínas Nucleares/metabolismo , Nucleosomas/química , Nucleosomas/metabolismo , Fosforilación , Regiones Promotoras Genéticas/genética , Proteína-Arginina N-Metiltransferasas/metabolismo , Receptores Citoplasmáticos y Nucleares/metabolismo , Proteínas Represoras/metabolismo , Factores de Transcripción/fisiología
18.
Proc Natl Acad Sci U S A ; 101(12): 4047-52, 2004 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-15016912

RESUMEN

Ataxin 1 (Atx1) is a foci-forming polyglutamine protein of unknown function, whose mutant form causes type 1 spinocerebellar ataxia in humans and exerts neurotoxicity in transgenic mouse and fly expressing mutant Atx1. In this study, we demonstrate that Atx1 interacts with the transcriptional corepressor SMRT (silencing mediator of retinoid and thyroid hormone receptors) and with histone deacetylase 3. Atx1 binds chromosomes and mediates transcriptional repression when tethered to DNA. Interaction with SMRT-related factors is a conserved feature of Atx1, because Atx1 also binds SMRTER, a Drosophila cognate of SMRT. Significantly, mutant Atx1 forms aggregates in Drosophila, and such mutant Atx1-mediated aggregates sequester SMRTER. Consistently, the neurodegenerative eye phenotype caused by mutant Atx1 is enhanced by a Smrter mutation and, conversely, is suppressed by a chromosomal duplication that contains the wild type Smrter gene. Together, our results suggest that Atx1 is a transcriptional factor whose mutant form exerts its deleterious effects in part by perturbing corepressor-dependent transcriptional pathways.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Proteínas Nucleares/metabolismo , Receptores de Ácido Retinoico/metabolismo , Receptores de Hormona Tiroidea/metabolismo , Proteínas Represoras/metabolismo , Animales , Ataxina-1 , Ataxinas , Proteínas Co-Represoras , Drosophila/genética , Drosophila/metabolismo , Proteínas de Drosophila/metabolismo , Anomalías del Ojo/genética , Anomalías del Ojo/metabolismo , Histona Desacetilasas/metabolismo , Mutación , Proteínas del Tejido Nervioso/genética , Proteínas Nucleares/genética , Co-Represor 2 de Receptor Nuclear , Receptores Citoplasmáticos y Nucleares/metabolismo , Levaduras/metabolismo
19.
Proc Natl Acad Sci U S A ; 100(15): 8892-7, 2003 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-12857950

RESUMEN

A hallmark of most neurodegenerative diseases, including those caused by polyglutamine expansion, is the formation of ubiquitin (Ub)-positive protein aggregates in affected neurons. This finding suggests that the Ub system may be involved in common mechanisms underlying these otherwise unrelated diseases. Here we report the finding of ataxin-3 (Atx-3), whose mutation is implicated in the neurodegenerative disease spinocerebellar ataxia type 3, in a bioinformatics search of the human genome for components of the Ub system. We show that wild-type Atx-3 is a Ub-binding protein and that the interaction of Atx-3 with Ub is mediated by motifs homologous to those found in a proteasome subunit. Both wild-type Atx-3 and the otherwise unrelated Ub-binding protein p62/Sequestosome-1 have been shown to be sequestered into aggregates in affected neurons in several neurodegenerative diseases, but the mechanism for this recruitment has remained unclear. In this article, we show that functional Ub-binding motifs in Atx-3 and p62 proteins are required for the localization of both proteins into aggregates in a cell-based assay that recapitulates several features of polyglutamine disease. We propose that the Ub-mediated sequestration of essential Ub-binding protein(s) into aggregates may be a common mechanism contributing to the pathogenesis of neurodegenerative diseases.


Asunto(s)
Péptidos/metabolismo , Proteínas/química , Proteínas/metabolismo , Ubiquitina/metabolismo , Proteínas Adaptadoras Transductoras de Señales , Secuencias de Aminoácidos , Secuencia de Aminoácidos , Animales , Ataxina-3 , Sitios de Unión/genética , Proteínas Portadoras/química , Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , Línea Celular , Cisteína Endopeptidasas/genética , Cisteína Endopeptidasas/metabolismo , Humanos , Proteínas Inmediatas-Precoces/química , Proteínas Inmediatas-Precoces/genética , Proteínas Inmediatas-Precoces/metabolismo , Técnicas In Vitro , Datos de Secuencia Molecular , Complejos Multienzimáticos/genética , Complejos Multienzimáticos/metabolismo , Mutación , Proteínas del Tejido Nervioso/química , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Enfermedades Neurodegenerativas/etiología , Enfermedades Neurodegenerativas/genética , Enfermedades Neurodegenerativas/metabolismo , Proteínas Nucleares , Péptidos/química , Complejo de la Endopetidasa Proteasomal , Proteínas/genética , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Proteínas Represoras , Homología de Secuencia de Aminoácido , Proteína Sequestosoma-1 , Transfección , Ubiquitina/química
20.
Ann Plast Surg ; 50(3): 292-5, 2003 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12800907

RESUMEN

Based on the detailed anatomy, the orbicularis oculi muscle and the orbital septum are the continuation of the frontalis muscle and its fascia. Therefore, the shortened orbicularis oculi muscle and orbital septum would transmit the frontalis muscle action more effectively. The superior-based orbicularis oculi muscle and orbital septum flap, as a single flap, were advanced and attached to the tarsal plate for the correction of blepharoptosis. Six patients with undercorrected blepharoptosis were included in this study. Each patient had undergone more than two levator resection procedures by ophthalmologists or plastic surgeons. Conventionally, the frontalis suspension procedure was the next choice in these cases. The shortened orbicularis oculi muscle and orbital septum flap was used in these cases. Postoperative results were satisfactory after 3-year follow-up.


Asunto(s)
Blefaroptosis/cirugía , Músculos Oculomotores/cirugía , Procedimientos Quirúrgicos Oftalmológicos/métodos , Colgajos Quirúrgicos , Adulto , Blefaroptosis/congénito , Femenino , Humanos , Persona de Mediana Edad , Reoperación , Resultado del Tratamiento
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