Telomeric Silencing
Mostrando 1-12 de 58 artigos, teses e dissertações.
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1. Estudo de interações proteicas da Tiorredoxina Peroxidase Nuclear (nTPx) de Sacharomyces cerevisiae nos eventos de crescimento celular e silenciamento telomérico
As tiorredoxinas peroxidases (TPx), constituem um grupo de proteínas antioxidantes que vêm sendo bastante estudadas pela sua atuação na decomposição de diversos tipos peróxidos, como o H2O2, peroxinitritos e peróxidos orgânicos. A capacidade de decomposição de peróxidos pelas TPx está relacionada a presença de uma cisteína conservada denominad
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 26/08/2011
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2. Mutational Analysis Defines a C-Terminal Tail Domain of Rap1 Essential for Telomeric Silencing in Saccharomyces Cerevisiae
Alleles specifically defective in telomeric silencing were generated by in vitro mutagenesis of the yeast RAP1 gene. The most severe phenotypes occur with three mutations in the C-terminal 28 amino acids. Two of the alleles are nonsense mutations resulting in truncated repressor/activator protein 1 (RAP1) species lacking the C-terminal 25-28 amino acids; the
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3. Tethered Sir3p nucleates silencing at telomeres and internal loci in Saccharomyces cerevisiae.
Rap1p binds to sites embedded within the Saccharomyces cerevisiae telomeric TG1-3 tract. Previous studies have led to the hypothesis that Rap1p may recruit Sir3p and Sir3p-associating factors to the telomere. To test this, we tethered Sir3p adjacent to the telomere via LexA binding sites in the rap1-17 mutant that truncates the Rap1p C-terminal 165 amino aci
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4. Type B Histone Acetyltransferase Hat1p Participates in Telomeric Silencing
Hat1p and Hat2p are the two subunits of a type B histone acetyltransferase from Saccharomyces cerevisiae that acetylates free histone H4 on lysine 12 in vitro. However, the role for these gene products in chromatin function has been unclear, as deletions of the HAT1 and/or HAT2 gene displayed no obvious phenotype. We have now identified a role for Hat1p and
American Society for Microbiology.
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5. Telomeric Position Effect Variegation in Saccharomyces cerevisiae by Caenorhabditis elegans Linker Histones Suggests a Mechanistic Connection between Germ Line and Telomeric Silencing
Linker histones are nonessential for the life of single-celled eukaryotes. Linker histones, however, can be important components of specific developmental programs in multicellular animals and plants. For Caenorhabditis elegans a single linker histone variant (H1.1) is essential in a chromatin silencing process which is crucial for the proliferation and diff
American Society for Microbiology.
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6. Lysine methylation within the globular domain of histone H3 by Dot1 is important for telomeric silencing and Sir protein association
The amino-terminal histone tails are subject to covalent post-translational modifications such as acetylation, methylation, and phosphorylation. In the histone code hypothesis, these exposed and unstructured histone tails are accessible to a repertoire of regulatory factors that specifically recognize the various modified histones, thereby generating altered
Cold Spring Harbor Laboratory Press.
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7. Ku-deficient yeast strains exhibit alternative states of silencing competence
In Saccharomyces cerevisiae, efficient silencer function requires telomere proximity, i.e. compartments of the nucleoplasm enriched in silencing factors. Accordingly, silencers located far from telomeres function inefficiently. We show here that cells lacking yKu balance between two mitotically stable states of silencing competence. In one, a partial delocal
Oxford University Press.
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8. The ubiquitin-conjugating enzyme Rad6 (Ubc2) is required for silencing in Saccharomyces cerevisiae.
It has been previously shown that genes transcribed by RNA polymerase II (RNAP II) are subject to position effect variegation when located near yeast telomeres. This telomere position effect requires a number of gene products that are also required for silencing at the HML and HMR loci. Here, we show that a null mutation of the DNA repair gene RAD6 reduces s
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9. Genetic Analysis of Rap1p/Sir3p Interactions in Telomeric and Hml Silencing in Saccharomyces Cerevisiae
We have identified three SIR3 suppressors of the telomeric silencing defects conferred by missense mutations within the Rap1p C-terminal tail domain (aa 800-827). Each SIR3 suppressor was also capable of suppressing a rap1 allele (rap1-21), which deletes the 28 aa C-terminal tail domain, but none of the suppressors restored telomeric silencing to a 165 amino
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10. A cytosolic NAD-dependent deacetylase, Hst2p, can modulate nucleolar and telomeric silencing in yeast
In budding yeast, the silent information regulator Sir2p is a nuclear NAD-dependent deacetylase that is essential for both telomeric and rDNA silencing. All eukaryotic species examined to date have multiple homologues of Sir two (HSTs), which share a highly conserved globular core domain. Here we report that yeast Hst2p and a mammalian Hst2p homologue, hSirT
Oxford University Press.
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11. mRNAs Encoding Telomerase Components and Regulators Are Controlled by UPF Genes in Saccharomyces cerevisiae
Telomeres, the chromosome ends, are maintained by a balance of activities that erode and replace the terminal DNA sequences. Furthermore, telomere-proximal genes are often silenced in an epigenetic manner. In Saccharomyces cerevisiae, average telomere length and telomeric silencing are reduced by loss of function of UPF genes required in the nonsense-mediate
American Society for Microbiology.
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12. The Function of DNA Polymerase α at Telomeric G Tails Is Important for Telomere Homeostasis
Telomere length control is influenced by several factors, including telomerase, the components of telomeric chromatin structure, and the conventional replication machinery. Although known components of the replication machinery can influence telomere length equilibrium, little is known about why mutations in certain replication proteins cause dramatic telome
American Society for Microbiology.