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Plos Biology : Coordinate Gene Regulation During Hematopoiesis is ...

By: Tom Misteli

Description : Gene loci are found in nuclear subcompartments that are related to their expression status. For instance, silent genes are often localized to heterochromatin and the nuclear periphery, whereas active genes tend to be found in the nuclear center. Evidence also suggests that chromosomes may be specifically positioned within the nucleus: however, the nature of this organization and how it is achieved are not yet fully understood. To examine whether gene regula...

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Plos Biology : Can Farmed and Wild Salmon Coexist, Volume 6

By: Liza Gross
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Plos Biology : the Geographic Spread of the Ccr5 D32 Hiv-resistanc...

By: Andy Clark

Description : The D32 mutation at the CCR5 locus is a well-studied example of natural selection acting in humans. The mutation is found principally in Europe and western Asia, with higher frequencies generally in the north. Homozygous carriers of the D32 mutation are resistant to HIV-1 infection because the mutation prevents functional expression of the CCR5 chemokine receptor normally used by HIV-1 to enter CD4þ T cells. HIV has emerged only recently, but population gen...

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Plos Biology : a Post-burst Afterdepolarization is Mediated by Gro...

By: Alberto Bacci

Description : Activation of group I metabotropic glutamate receptors (subtypes mGluR1 and mGluR5) regulates neural activity in a variety of ways. In CA1 pyramidal neurons, activation of group I mGluRs eliminates the post-burst afterhyperpolarization (AHP) and produces an afterdepolarization (ADP) in its place. Here we show that upregulation of Cav2.3 R-type calcium channels is responsible for a component of the ADP lasting several hundred milliseconds. This medium-durati...

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Plos Biology : a Neural Computation for Visual Acuity in the Prese...

By: David Burr

Description : Humans can distinguish visual stimuli that differ by features the size of only a few photoreceptors. This is possible despite the incessant image motion due to fixational eye movements, which can be many times larger than the features to be distinguished. To perform well, the brain must identify the retinal firing patterns induced by the stimulus while discounting similar patterns caused by spontaneous retinal activity. This is a challenge since the traject...

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Plos Biology : Putting Beta-diversity on the Map ; Broad-scale Con...

By: Georgina M. MacE

Description : Beta-diversity, the change in species composition between places, is a critical but poorly understood component of biological diversity. Patterns of beta-diversity provide information central to many ecological and evolutionary questions, as well as to conservation planning. Yet beta-diversity is rarely studied across large extents, and the degree of similarity of patterns among taxa at such scales remains untested. To our knowledge, this is the first broad...

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Plos Biology : when Two is Better Than One ; Elements of Intravita...

By: Piston David W.
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Plos Biology : Aging in a Long-lived Clonal Tree, Volume 8

By: Thomas B. L. Kirkwood

Description : From bacteria to multicellular animals, most organisms exhibit declines in survivorship or reproductive performance with increasing age (‘‘senescence’’) [1,2]. Evidence for senescence in clonal plants, however, is scant [3,4]. During asexual growth, we expect that somatic mutations, which negatively impact sexual fitness, should accumulate and contribute to senescence, especially among long-lived clonal plants [5,6]. We tested whether older clones of Populu...

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Plos Biology : Generalization of Motor Learning Depends on the His...

By: James Ashe

Description : Generalization of motor learning refers to our ability to apply what has been learned in one context to other contexts. When generalization is beneficial, it is termed transfer, and when it is detrimental, it is termed interference. Insight into the mechanism of generalization may be acquired from understanding why training transfers in some contexts but not others. However, identifying relevant contextual cues has proven surprisingly difficult, perhaps bec...

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Plos Biology : Distinct Mammalian Precursors Are Committed to Gene...

By: Jeffrey MacKlis

Description : The mechanisms that regulate how dendrites target different neurons to establish connections with specific cell types remain largely unknown. In particular, the formation of cell-type–specific connectivity during postnatal neurogenesis could be either determined by the local environment of the mature neuronal circuit or by cell-autonomous properties of the immature neurons, already determined by their precursors. Using retroviral fate mapping, we studied th...

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Plos Biology : Comparative Sex Chromosome Genomics in Snakes ; Dif...

By: Nick H. Barton

Description : Snakes exhibit genetic sex determination, with female heterogametic sex chromosomes (ZZ males, ZW females). Extensive cytogenetic work has suggested that the level of sex chromosome heteromorphism varies among species, with Boidae having entirely homomorphic sex chromosomes, Viperidae having completely heteromorphic sex chromosomes, and Colubridae showing partial differentiation. Here, we take a genomic approach to compare sex chromosome differentiation in ...

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Plos Biology : Insights Into How Calcium Forms Plaques in Arteries...

By: Janelle Weaver
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Plos Biology : Intermingling of Chromosome Territories in Interpha...

By: Peter Becker

Description : After mitosis, mammalian chromosomes partially decondense to occupy distinct territories in the cell nucleus. Current models propose that territories are separated by an interchromatin domain, rich in soluble nuclear machinery, where only rare interchromosomal interactions can occur via extended chromatin loops. In contrast, recent evidence for chromatin mobility and high frequency of chromosome translocations are consistent with significant levels of chrom...

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Plos Biology : Engineering Sexless Seeds as a Path to High-yield C...

By: Robin Meadows
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Plos Biology : Citation Advantage of Open Access Articles, Volume 4

By: Carol Tenopir

Description : Open access (OA) to the research literature has the potential to accelerate recognition and dissemination of research findings, but its actual effects are controversial. This was a longitudinal bibliometric analysis of a cohort of OA and non- OA articles published between June 8, 2004, and December 20, 2004, in the same journal (PNAS : Proceedings of the National Academy of Sciences). Article characteristics were extracted, and citation data were compared b...

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Plos Biology : Auditory Cortex Tracks Both Auditory and Visual Sti...

By: Robert Zatorre

Description : Integrating information across sensory domains to construct a unified representation of multi-sensory signals is a fundamental characteristic of perception in ecological contexts. One provocative hypothesis deriving from neurophysiology suggests that there exists early and direct cross-modal phase modulation. We provide evidence, based on magnetoencephalography (MEG) recordings from participants viewing audiovisual movies, that low-frequency neuronal inform...

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Plos Biology : Neuroscience, Ethics, and National Security ; the S...

By: Jonathan D. Moreno

Description : National security organizations in the United States, including the armed services and the intelligence community, have developed a close relationship with the scientific establishment. The latest technology often fuels warfighting and counter-intelligence capacities, providing the tactical advantages thought necessary to maintain geopolitical dominance and national security. Neuroscience has emerged as a prominent focus within this milieu, annually receivi...

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Plos Biology : Does Bacteriophage Φ29 Pack Its Dna with a Twist, V...

By: Mary Hoff
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Plos Biology : a New Model for Open Sharing ; Massachusetts Instit...

By: Anne H. Margulies
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Plos Biology : Progress Toward Public Access to Science, Volume 6

By: Harold Varmus
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