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1.
J Neurol ; 259(2): 334-41, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21808983

RESUMO

Despite the devastating motor impairment, a significant number of patients with amyotrophic lateral sclerosis (ALS) maintain a good psychosocial adjustment. Here we investigated whether this is specific for ALS or a more general characteristic of terminal disease. Psychosocial adjustment was investigated in 30 ALS patients, 29 cancer patients in palliative treatment and 29 age-, gender- and level of education-matched healthy controls. Subjective quality of life (sQoL), degree of depressive symptoms and coping were evaluated as measures of psychosocial adjustment. Personality factors were described. ALS and cancer patients showed a good psychosocial adjustment. Subjective QoL and depression did not differ significantly. Both patient groups presented a good sQoL. The level of mild depressive symptoms in both patient groups was similar and none showed clinically relevant depression. ALS patients expressed fewer active coping strategies than cancer patients which were explained by gender differences. Both patient groups showed comparable psychosocial adjustment to their disease. Overall, in terminally ill patients the psychological response to the prognosis is not associated with neurobiological changes (e.g., associated with subclinical deficits in ALS) or with physical decline.


Assuntos
Adaptação Psicológica , Esclerose Lateral Amiotrófica/psicologia , Qualidade de Vida , Ajustamento Social , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
2.
EMBO J ; 30(18): 3823-9, 2011 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-21822213

RESUMO

Although the decision between stem cell self-renewal and differentiation has been linked to cell-cycle modifications, our understanding of cell-cycle regulation in stem cells is very limited. Here, we report that FBF/Pumilio, a conserved RNA-binding protein, promotes self-renewal of germline stem cells by repressing CKI-2(Cip/Kip), a Cyclin E/Cdk2 inhibitor. We have previously shown that repression of CYE-1 (Cyclin E) by another RNA-binding protein, GLD-1/Quaking, promotes germ cell differentiation. Together, these findings suggest that a post-transcriptional regulatory circuit involving FBF and GLD-1 controls the self-renewal versus differentiation decision in the germline by promoting high CYE-1/CDK-2 activity in stem cells, and inhibiting CYE-1/CDK-2 activity in differentiating cells.


Assuntos
Proteínas de Caenorhabditis elegans/antagonistas & inibidores , Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/fisiologia , Ciclo Celular , Proteínas Inibidoras de Quinase Dependente de Ciclina/antagonistas & inibidores , Regulação da Expressão Gênica , Proteínas de Ligação a RNA/metabolismo , Células-Tronco/fisiologia , Animais , Células Cultivadas
3.
J Biol Chem ; 280(46): 38117-20, 2005 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-16150737

RESUMO

G4-DNA is a highly stable alternative DNA structure that can form spontaneously in guanine-rich regions of single-stranded DNA under physiological conditions. Since a number of biological processes create such single-stranded regions, G4-DNA occurrence must be regulated. To date, resolution of tetramolecular G4-DNA into single strands (G4-resolvase activity) has been observed only in recombinant RecQ DNA helicases. We previously reported that human cell lysates possess tetramolecular G4-DNA resolving activity (Harrington, C., Lan, Y., and Akman, S. (1997) J. Biol Chem. 272, 24631-24636). Here we report the first complete purification of a major non-RecQ, NTP-dependent G4-DNA resolving enzyme from human cell lysates. This enzyme is identified as the DEXH helicase product of gene DHX36 (also known as RHAU). G4-DNA resolving activity was captured from HeLa cell lysates on G4-DNA affinity beads and further purified by gel filtration chromatography. The DHX36 gene product was identified by mass spectrometric sequencing of a tryptic digest from the protein band on SDS-PAGE associated with activity. DHX36 was cloned within a His(6)-tagging vector, expressed, and purified from Escherichia coli. Inhibition and substrate resolution assays showed that recombinant DHX36 protein displayed robust, highly specific G4-DNA resolving activity. Immunodepletion of HeLa lysates by a monoclonal antibody to the DHX36 product removed ca. 77% of the enzyme from lysates and reduced G4-DNA resolving activity to 46.0 +/- 0.4% of control, demonstrating that DHX36 protein is responsible for the majority of tetramolecular G4-DNA resolvase activity.


Assuntos
DNA Helicases/genética , DNA Helicases/fisiologia , RNA Helicases/genética , RNA Helicases/fisiologia , Recombinases/química , Trifosfato de Adenosina/química , Anticorpos Monoclonais/química , Western Blotting , Cromatografia de Afinidade/métodos , Cromatografia em Gel , Clonagem Molecular , RNA Helicases DEAD-box , DNA/química , DNA/genética , Eletroforese em Gel de Poliacrilamida , Escherichia coli/metabolismo , Quadruplex G , Guanina/química , Células HeLa , Histidina/química , Humanos , Imunoglobulina G/química , Espectrometria de Massas/métodos , Conformação de Ácido Nucleico , Ligação Proteica , RNA Mensageiro/metabolismo , Proteínas Recombinantes/química , Estreptavidina/química , Especificidade por Substrato
4.
J Virol ; 78(22): 12120-8, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15507598

RESUMO

A 60-nucleotide region (S1) downstream of the transcription start site of the cauliflower mosaic virus 35S RNA can enhance gene expression. By using transient expression assays with plant protoplasts, this activity was shown to be at least partially due to the effect of transcriptional enhancers within this region. We identify sequence motifs with enhancer function, which are normally masked by the powerful upstream enhancers of the 35S promoter. A repeated CT-rich motif is involved both in enhancer function and in interaction with plant nuclear proteins. The S1 region can also enhance expression from heterologous promoters.


Assuntos
Caulimovirus/genética , Regiões Promotoras Genéticas , Transcrição Gênica , Sequência de Bases , Elementos Facilitadores Genéticos/fisiologia , Dados de Sequência Molecular , Proteínas Nucleares/metabolismo
5.
Plant Mol Biol ; 53(5): 663-73, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15010605

RESUMO

Appropriately regulated gene expression requires a suitable promoter. A number of promoters have been isolated and shown to be functional in plants, but only a few of them activate transcription of transgenes at high levels constitutively. We report here the cloning and characterization of a novel, constitutively expressed promoter isolated from Cestrum yellow leaf curling virus (CmYLCV), a double-stranded DNA plant pararetrovirus belonging to the Caulimoviridae family. The CmYLCV promoter is highly active in callus, meristems and vegetative and reproductive tissues in Arabidopsis thaliana, Nicotiana tabacum, Lycopersicon esculentum, Zea mays and Oryza sativa. Furthermore, the level of expression is comparable to, or higher than, that from the CaMV 35S, the 'super-promoter' or the maize ubiquitin 1 promoters, three frequently used promoters in agricultural biotechnology. The heritable, strong and constitutive activity in both monocotyledonous and dicotyledonous plants, combined with the extremely narrow CmYLCV host range, makes the CmYLCV promoter an attractive tool for regulating transgene expression in a wide variety of plant species.


Assuntos
Caulimovirus/genética , Cestrum/virologia , Plantas Geneticamente Modificadas/genética , Regiões Promotoras Genéticas/genética , Arabidopsis/genética , Arabidopsis/metabolismo , Ensaio de Imunoadsorção Enzimática , Dosagem de Genes , Expressão Gênica , Glucuronidase/genética , Glucuronidase/metabolismo , Proteínas de Fluorescência Verde , Histocitoquímica , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Solanum lycopersicum/genética , Solanum lycopersicum/metabolismo , Microscopia de Fluorescência , Oryza/genética , Oryza/metabolismo , Plasmídeos/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Nicotiana/genética , Nicotiana/metabolismo , Transgenes/genética , Zea mays/genética , Zea mays/metabolismo
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