Bio-Med Roundup

This month in Bio-Med Roundup:
    • Gogolla et al. reported that fearful memories are difficult to erase because of the physical environment of specific neurons in the brain.
    • Cermeño and Falkowski and Hubert et al. shed light on the dispersal of marine microbes.
    • Holt et al. and Tan et al. offered insights into the evolution of the topology and distribution of protein phosphorylation sites.
    • Medlock and Galvani proposed that age-related patterns of influenza transmission should be incorporated into vaccine distribution policy to minimize the impact of epidemics.
Jump to:

CELL BIOLOGY

Rab35 Controls Actin Bundling by Recruiting Fascin as an Effector Protein (4 September 2009)
J. Zhang et al.
Development of sensory bristles in flies depends on controlling the colocalization of actin assembly on membranes.
 
Regulation of Histone Acetylation in the Nucleus by Sphingosine-1-Phosphate (4 September 2009)
N. C. Hait et al.
A phospholipid that binds to nuclear enzymes modifies gene transcription in response to external stimuli. 

The RNA-Binding Protein NANOS2 Is Required to Maintain Murine Spermatogonial Stem Cells (11 September 2009)
A. Sada et al.
Cell lineage tracing reveals the factor that preserves stem cells in the undifferentiated state in the mouse male germ line. 

Activation of Rho GTPases by DOCK Exchange Factors Is Mediated by a Nucleotide Sensor (11 September 2009)
J. Yang et al.
Crystal structures reveal the mechanism of a nucleotide exchange factor regulating cytoskeleton and cell signaling networks. 

D-Amino Acids Govern Stationary Phase Cell Wall Remodeling in Bacteria (18 September 2009)
H. Lam et al.
Bacteria produce D-amino acids to regulate their cell wall composition, structure, amount, and strength. 
See related Perspective

Global Analysis of Cdk1 Substrate Phosphorylation Sites Provides Insights into Evolution (25 September 2009)
L. J. Holt et al.
The range of sites phosphorylated by a protein kinase in yeast provides clues to the evolution of such regulatory mechanisms. 
See related Perspective

Positive Selection of Tyrosine Loss in Metazoan Evolution (25 September 2009)
C. S. H. Tan et al.
Evolution of tyrosine phosphorylation as a signaling mechanism may have coincided with loss of tyrosine residues to avoid noise. 
See related Perspective


NEUROSCIENCE

Perineuronal Nets Protect Fear Memories from Erasure (4 September 2009)
N. Gogolla et al.
Fearful memories in adults are difficult to erase because of the physical environment of specific neurons in the brain. 
See related Perspective

A G Protein–Coupled Receptor Is Essential for Schwann Cells to Initiate Myelination (11 September 2009)
K. R. Monk et al.
A G protein–coupled receptor family member elevates cyclic adenosine monophosphate in Schwann cells to trigger myelination in zebrafish. 
See related Perspective

Energy-Efficient Action Potentials in Hippocampal Mossy Fibers (11 September 2009)
H. Alle et al.
Mammalian neurons have developed highly efficient ways to limit energy consumption while propagating neuronal information. 
See related Perspective

Cellular Basis of Itch Sensation (18 September 2009)
Y.-G. Sun et al.
Itch, but not pain sensation, is abolished by selective ablation of a small subpopulation of spinal neurons. 


BIOCHEMISTRY

A Dimeric Structure for Archaeal Box C/D Small Ribonucleoproteins (11 September 2009)
F. Bleichert et al.
Electron microscopy and single-particle analysis show that a small nuclear ribonucleoprotein forms a dimeric structure. 

An Acidic Matrix Protein, Pif, Is a Key Macromolecule for Nacre Formation (11 September 2009)
M. Suzuki et al.
A matrix protein is identified that regulates nacre formation in the Japanese pearl oyster. 
See related Perspective

Three-Dimensional Structural View of the Central Metabolic Network of Thermotoga maritima (18 September 2009)
Y. Zhang et al.
Protein structure and biochemical data generate a three-dimensional view of the metabolic network of a bacterial cell. 

Details of Insect Wing Design and Deformation Enhance Aerodynamic Function and Flight Efficiency (18 September 2009)
J. Young et al.
Measurements of locust wing kinematics validate a fluid dynamics model of the aerodynamic effects of wing deformation. 


MICROBIOLOGY/VIROLOGY

Endogenous Nitric Oxide Protects Bacteria Against a Wide Spectrum of Antibiotics (11 September 2009)
I. Gusarov et al.
Bacteria deploy nitric oxide synthases to counter oxidative stress from natural toxins and antibiotic drugs. 

Macroevolution of Complex Retroviruses (18 September 2009)
A. Katzourakis et al.
A sloth foamy virus sequence indicates that mammals have been infected since the Cretaceous. 

Controls on Diatom Biogeography in the Ocean (18 September 2009)
P. Cermeño and P. G. Falkowski
Fossil records show that the dispersal of diatoms from ocean plankton has not been constrained by geographical barriers. 
See related Perspective

A Constant Flux of Diverse Thermophilic Bacteria into the Cold Arctic Seabed (18 September 2009)
C. Hubert et al.
Spore-forming bacteria adapted to the hot subsurface biosphere are continually deposited in polar marine sediments. 
See related Perspective.

Chloroquine Transport via the Malaria Parasite’s Chloroquine Resistance Transporter (25 September 2009)
R. E. Martin et al.
Chloroquine resistance in Plasmodium falciparum is due to the direct export of the drug via a mutant transporter protein. 


PSYCHOLOGY/SOCIOLOGY

Differential Sensitivity to Human Communication in Dogs, Wolves, and Human Infants (4 September 2009)
J. Topál et al.
Social interactions with humans govern the way dogs and children learn, but wolves learn by focusing on objects. 

Positive Interactions Promote Public Cooperation (4 September 2009)
D. G. Rand et al.
Reward is as good as punishment to promote cooperation, costs less, and increases the share out of resources up for grabs. 
See related Perspective

Attitudes and Action: Public Opinion and the Occurrence of International Terrorism (18 September 2009)
A. B. Krueger and J. Maleková
Public opinion toward a country is associated with the occurrence of terrorism against that country. 

On Universality in Human Correspondence Activity (25 September 2009)
R. D. Malmgren et al.
Affinity toward a particular life-style affects the communication patterns between people. 


GENETICS

Common Regulatory Variation Impacts Gene Expression in a Cell Type–Dependent Manner (4 September 2009)
A. S. Dimas et al.
Genetic variation in regulatory elements among humans affects gene expression in a tissue-specific manner. 

Tuned for Transposition: Molecular Determinants Underlying the Hyperactivity of a Stowaway MITE (11 September 2009)
G. Yang et al.
A transposable element in rice enhances its own transposition using another unrelated element’s transposase. 
See related Perspective

Creating Bacterial Strains from Genomes That Have Been Cloned and Engineered in Yeast (25 September 2009)
C. Lartigue et al.
A Mycoplasma mycoides genome was engineered in yeast and then transplanted into M. capricolum cells to produce a new strain. 

Evolution of a Novel Phenolic Pathway for Pollen Development (25 September 2009)
M. Matsuno et al.
Gene copying and positive Darwinian selection promoted the emergence of a phenolic pathway in Brassicaceae. 


MEDICINE

Activation of the PI3K Pathway in Cancer Through Inhibition of PTEN by Exchange Factor P-REX2a (4 September 2009)
B. Fine et al.
Cancer cell growth is stimulated by the inhibition of a previously unknown step in cell signaling for tumor suppression. 

Glucose Deprivation Contributes to the Development of KRAS Pathway Mutations in Tumor Cells (18 September 2009)
J. Yun et al.
Glucose deprivation can drive the acquisition of certain oncogenic mutations in human cancer cells. 

Optimizing Influenza Vaccine Distribution (25 September 2009)
J. Medlock and A. P. Galvani
Age-related transmission patterns should be incorporated into vaccine distribution policy to minimize the impact of epidemics. 


MOLECULAR BIOLOGY

Poly(ADP-ribose)–Dependent Regulation of DNA Repair by the Chromatin Remodeling Enzyme ALC1 (4 September 2009)
D. Ahel et al.
A chromatin remodeling complex targeted by poly(ADP ribosyl)ation plays a role in DNA repair. 


IMMUNOLOGY

Recruitment of Antigen-Specific CD8+ T Cells in Response to Infection Is Markedly Efficient (4 September 2009)
J. W. J. van Heijst et al.
Lymphocyte proliferation, more than recruitment to the site of an infection, determines the success of the immune response. 


PHYSIOLOGY

Antennal Circadian Clocks Coordinate Sun Compass Orientation in Migratory Monarch Butterflies (25 September 2009)
C. Merlin et al.
Monarch butterfly antennae contain the timing mechanism for time-compensated Sun compass orientation. 
See related Perspective.