This month in BioMed Roundup:

• Parvanov et al., Baudat et al., and Myers et al. identified a chromatin-modifying enzyme as a determinant of mammalian recombination hotspots.
• Wang et al. generated a recombinant prion protein that recapitulates the characteristics of the infectious agent in prion disease.
• Zhao et al. and Wang et al. showed that regulation of enzymes by acetylation controls metabolic function in bacteria and human cells.
• Smith? et al. presented modeling data which indicate the potential for an epidemic wave of drug-resistant HIV.

Jump to:

• Genetics
• Neuroscience
• Biochemistry
• Cell Biology
• Molecular Biology
• Medicine
• Microbiology
• Molecular Biology
• Psychology
• Plant Science

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GENETICS

Prdm9 Controls Activation of Mammalian Recombination Hotspots (12 February 2010)
E. D. Parvanov et al.
Genome recombination during meiosis is likely controlled by a chromatin-modifying enzyme.
See related Perspective

PRDM9 Is a Major Determinant of Meiotic Recombination Hotspots in Humans and Mice (12 February 2010)
F. Baudat et al.
A chromatin-modifying enzyme is implicated in the determination of recombination loci within the genome.
See related Perspective

Drive Against Hotspot Motifs in Primates Implicates the PRDM9 Gene in Meiotic Recombination (12 February 2010)
S. Myers et al.
Bioinformatics identifies a chromatin-modifying enzyme as a factor in determining recombination hotspots.
See related Perspective

A Composite of Multiple Signals Distinguishes Causal Variants in Regions of Positive Selection (12 February 2010)
S. R. Grossman et al.
Combining statistical methods detects signals of selection with increased sensitivity and a lower false-positive rate.


NEUROSCIENCE

Optimal Localization by Pointing Off Axis (5 February 2010)
Y. Yovel et al.
Echolocating Egyptian fruit bats do not center their sonar clicks on a target, thereby maximizing localization of the target.

Axon Extension Occurs Independently of Centrosomal Microtubule Nucleation (5 February 2010)
M. Stiess et al.
Neuronal polarization and axon regeneration depend on decentralized microtubule assembly rather than a functional centrosome.

A Genetic Variant BDNF Polymorphism Alters Extinction Learning in Both Mouse and Human (12 February 2010)
F. Soliman et al.
A common genetic variation affecting fear learning and extinction operates through the same pathways in mice and men.

Cortical Plasticity Induced by Inhibitory Neuron Transplantation (26 February 2010)
D. G. Southwell et al.
Plasticity in the mouse brain’s visual cortex can be re-induced by neurons embedded by an earlier transplantation.


BIOCHEMISTRY

Conformational Spread as a Mechanism for Cooperativity in the Bacterial Flagellar Switch (5 February 2010)
F. Bai et al.
The behavior of the bacterial flagellar switch is modeled by probabilistic conformational coupling of the protein.
See related Perspective

Cryo-EM Model of the Bullet-Shaped Vesicular Stomatitis Virus (5 February 2010)
P. Ge et al.
The structure of a negative-strand RNA virus suggests how bullet-shaped rhabdoviruses assemble.

Peptidomimetic Antibiotics Target Outer-Membrane Biogenesis in Pseudomonas aeruginosa (19 February 2010)
N. Srinivas et al.
A synthesized antibiotic targets a protein involved in outer-membrane biogenesis to selectively kill Pseudomonas pathogens.

NMR Structure Determination for Larger Proteins Using Backbone-Only Data (19 February 2010)
S. Raman et al.
Protein structures can be determined by using the limited nuclear magnetic resonance information obtainable for larger proteins.

Generating a Prion with Bacterially Expressed Recombinant Prion Protein (26 February 2010)
F. Wang et al.
Recombinant prion protein recapitulates the characteristics of the infectious agent in prion disease.
See related Perspective


CELL BIOLOGY

Darwinian Evolution of Prions in Cell Culture (12 February 2010)
J. Li et al.
When propagated in vitro, prion strains demonstrate adaptability and selection.

Repulsion of Superinfecting Virions: A Mechanism for Rapid Virus Spread (12 February 2010)
V. Doceul et al.
Early in infection, vaccinia virus exploits the actin cytoskeleton to promote rapid cell-to-cell spread.
See related Perspective

N-Terminal Acetylation of Cellular Proteins Creates Specific Degradation Signals (19 February 2010)
C.-S. Hwang et al.
In vivo protein stoichiometries are regulated through N-terminally acetylated degrons.
See related Perspective

Regulation of Cellular Metabolism by Protein Lysine Acetylation (19 February 2010)
S. Zhao et al.
Regulation of enzymes by acetylation controls metabolic function in human liver cells.
See related Perspective

Acetylation of Metabolic Enzymes Coordinates Carbon Source Utilization and Metabolic Flux (19 February 2010)
Q. Wang et al.
Reversible acetylation of metabolic enzymes helps bacteria adjust to changes in food resources.
See related Perspective

Inhibition of NF-κB Signaling by A20 Through Disruption of Ubiquitin Enzyme Complexes (26 February 2010)
N. Shembade et al.
The multifunctional A20 protein can act in diverse ways to limit receptor-induced inflammatory signaling.
See related Perspective

Photorhabdus luminescens Toxins ADP-Ribosylate Actin and RhoA to Force Actin Clustering (26 February 2010)
A. E. Lang et al.
A bacterial toxin targets and modifies the actin cytoskeleton in insect larvae.


MOLECULAR BIOLOGY

Abundance of Ribosomal RNA Gene Copies Maintains Genome Integrity (5 February 2010)
S. Ide et al.
In eukaryotes, multiple copies of ribosomal DNA protect it from transcription-induced replication damage.

Regulation of Alternative Splicing by Histone Modifications (19 February 2010)
R. F. Luco et al.
Histone modifications regulate alternativesplicing through physical cross talk with the splicing machinery.

Noise Can Induce Bimodality in Positive Transcriptional Feedback Loops Without Bistability (26 February 2010)
T.-L. To and N. Maheshri
Noise induced by multiple binding sites, rather than deterministic bistability, may cause bimodal gene expression in yeast.
See related Perspective


MEDICINE

Evolutionary Dynamics of Complex Networks of HIV Drug-Resistant Strains: The Case of San Francisco (5 February 2010)
R. J. Smith? et al.
Modeling of data from the U.S. indicates the potential for an epidemic wave of antiretroviral-resistant HIV.

The Lmo2 Oncogene Initiates Leukemia in Mice by Inducing Thymocyte Self-Renewal (12 February 2010)
M. P. McCormack et al.
Expression of an oncogene confers self-renewal activity to committed T cells in the thymus long before disease onset.


MICROBIOLOGY

Vibrio cholerae VpsT Regulates Matrix Production and Motility by Directly Sensing Cyclic di-GMP (12 February 2010)
P. V. Krasteva et al.
A bacterial signaling molecule induces the dimerization and activation of a biofilm-promoting transcription factor.


PSYCHOLOGY

Limits of Predictability in Human Mobility (19 February 2010)
C. Song et al.
Analysis of the trajectories of people carrying cell phones reveals that human mobility patterns are highly predictable.


PLANT SCIENCE

Plant Peptides Govern Terminal Differentiation of Bacteria in Symbiosis (26 February 2010)
W. Van de Velde et al.
A Nodule-Specific Protein Secretory Pathway Required for Nitrogen-Fixing Symbiosis (26 February 2010)
D. Wang et al.
Products encoded by the leguminous plant Medicago direct the differentiation of the bacterial partner in symbiosis.

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