Replicators
Mostrando 1-12 de 26 artigos, teses e dissertações.
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1. Ecossistemas de replicadores: uma abordagem via mecânica estatística de sistemas desordenados / Replicators ecosystems: a statistical mechanics of disordered systems approach
Nesta tese utilizamos o modelo do replicador aleatório, proposto por Diederich e Opper, para analisar as propriedades de equilíbrio de ecossistemas complexos (formados por um grande número de espécies) em três situações distintas. Na primeira parte desta tese, investigamos os efeitos de interações variáveis sobre a estrutura do ecossistema, utiliza
Publicado em: 2007
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2. Cooperação e Conflito em Modelos de Vesículas Pré-Bióticas / Cooperation and Conflict in Prebiotic Vesicle Models
The primordial genetic information crisis as defined by the Eigens quasispecies model, which can be used as a paradigm here, has been a challenge to any theory about the origin of life and prebiotic evolution for more than three decades. Despite several tentative solutions proposed along this period, theres no consensual solution to the scientific commun
Publicado em: 2006
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3. Model ecosystems with nonlinear interspecies interactions. / Modelos de ecossistemas com interações não lineares.
Neste trabalho investigamos as propriedade estatísticas de um modelo de coevolução de N espécies, sob a perspectiva da dinâmica de replicadores. As interações entre pares de espécies são dadas por variáveis aleatórias independentes, fixas no tempo. As interações são também simétricas, de modo que a dinâmica maximiza uma função de Lyapunov
Publicado em: 2004
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4. Lattice model of replicators: aplication on prebiotic models and herpes ulcer / Dinâmica de replicação na rede: aplicações em modelos de evolução pré-biótica e de formação de úlceras
Two fundamental questions in the study of prebiotic evolution (origin of life) are concerned to the requisites for the persistence of small colonies of self-replicating molecules (replicators) and to the possibility that complex organisms evolve from simpler organisms as a result of mutations. These issues have been studied mainly in the chemical kinetics fo
Publicado em: 2001
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5. The Human β-Globin Replication Initiation Region Consists of Two Modular Independent Replicators
Previous studies have shown that mammalian cells contain replicator sequences, which can determine where DNA replication initiates. However, the specific sequences that confer replicator activity were not identified. Here we report a detailed analysis of replicator sequences that dictate initiation of DNA replication from the human β-globin locus. This anal
American Society for Microbiology.
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6. The origin recognition complex interacts with a bipartite DNA binding site within yeast replicators.
Replicators are genetically defined elements within chromosomes that determine the location of origins of DNA replication. In the yeast Saccharomyces cerevisiae, the ARS1 replicator contains multiple functional DNA elements: an essential A element and three important B elements--B1, B2, and B3. Functionally similar A, B1, and B2 elements are also present in
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7. Functional conservation of multiple elements in yeast chromosomal replicators.
Replicators that control the initiation of DNA replication in the chromosomes of Saccharomyces cerevisiae retain their function when cloned into plasmids, where they are commonly referred to as autonomously replicating sequences (ARSs). Previous studies of the structure of ARS1 in both plasmid and chromosome contexts have shown that it contains one essential
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8. Replicator dominance in a eukaryotic chromosome.
Replicators are genetic elements that control initiation at an origin of DNA replication (ori). They were first identified in the yeast Saccharomyces cerevisiae as autonomously replicating sequences (ARSs) that confer on a plasmid the ability to replicate in the S phase of the cell cycle. The DNA sequences required for ARS function on a plasmid have been def
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9. Multiple DNA elements in ARS305 determine replication origin activity in a yeast chromosome.
A yeast autonomously replicating sequence, ARS305, shares essential components with a chromosome III replicator, ORI305. Known components include an ARS consensus sequence (ACS) element, presumed to bind the origin recognition complex (ORC), and a broad 3'-flanking sequence which contains a DNA unwinding element. Here linker substitution mutagenesis of ARS30
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10. The E1 Initiator Recognizes Multiple Overlapping Sites in the Papillomavirus Origin of DNA Replication
A common feature of replicator sequences from a variety of organisms is multiple binding sites for an initiator protein. By binding to the replicator, initiators mark the site and contribute to melting or distortion of the DNA. We have defined the recognition sequence for the papillomavirus E1 initiator and determined the arrangement of binding sites in the
American Society for Microbiology.
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11. The ARS309 chromosomal replicator of Saccharomyces cerevisiae depends on an exceptional ARS consensus sequence
Autonomously replicating sequence (ARS) elements, which function as the cis-acting chromosomal replicators in the yeast Saccharomyces cerevisiae, depend upon an essential copy of the 11-bp ARS consensus sequence (ACS) for activity. Analysis of the chromosome III replicator ARS309 unexpectedly revealed that its essential ACS differs from the canonical AC
The National Academy of Sciences of the USA.
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12. Part of the human ribosomal RNA locus stabilizes a plasmid in yeast.
Most yeast plasmids--particularly those containing chromosomal replicators (ARS)--are unstable and do not segregate equally to mother and daughter cells unless they contain centromeric sequences. We have screened a fraction of the human genome for sequences that stabilize YRp7, a plasmid containing ARS1. We selected a fraction which we hoped would be enriche