This month in Bio-Med Roundup:
- Becker et al. and Seidelt et al. used cryo-electron microscopy to visualize nascent polypeptide chains in the ribosomal tunnel.
- Weisbuch et al. showed that exposure to nonverbal behaviors can transmit race bias to observers.
- Williams et al. reported on a microRNA that promotes regeneration of neuromuscular synapses and delays progression of ALS in a mouse model.
- Moscou and Bogdanove and Boch et al. described the mechanism by which proteins of bacterial plant pathogens recognize and control the expression of host plant genes to promote infection.
BIOCHEMISTRY
Structure of Monomeric Yeast and Mammalian Sec61 Complexes Interacting with the Translating Ribosome (4 December 2009)
T. Becker et al.
A single copy of a protein-conducting channel molecule provides a conduit for polypeptide translocation across membranes.
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Structural Insight into Nascent Polypeptide Chain–Mediated Translational Stalling (4 December 2009)
B. Seidelt et al.
Individual polypeptide nascent chains can adopt distinct conformations within the ribosome exit tunnel.
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A Crystal Structure of the Bifunctional Antibiotic Simocyclinone D8, Bound to DNA Gyrase (4 December 2009)
M. J. Edwards et al.
The molecular mechanism is revealed by which an antibiotic prevents DNA binding by a bacterial DNA gyrase.
An Analytical Solution to the Kinetics of Breakable Filament Assembly (11 December 2009)
T. P. J. Knowles et al.
The growth kinetics of amyloid fibrils and related self-assembly phenomena are revealed by analytical theory.
Crystal Structure of the Eukaryotic Strong Inward-Rectifier K+ Channel Kir2.2 at 3.1 Å Resolution (18 December 2009)
X. Tao et al.
A structure reveals the basis of diode-like conduction properties and toxin insensitivity of these channels.
Structure of the LKB1-STRAD-MO25 Complex Reveals an Allosteric Mechanism of Kinase Activation (18 December 2009)
E. Zeqiraj et al.
A "pseudokinase" activates the LKB1 tumor suppressor protein without catalyzing phosphorylation.
CELL/DEVELOPMENTAL BIOLOGY
The Insect Neuropeptide PTTH Activates Receptor Tyrosine Kinase Torso to Initiate Metamorphosis (4 December 2009)
K. F. Rewitz et al.
The receptor of the Drosophila brain hormone that initiates metamorphosis is identified.
Planarian Hh Signaling Regulates Regeneration Polarity and Links Hh Pathway Evolution to Cilia (4 December 2009)
J. C. Rink et al.
Analysis of the Hedgehog signaling pathway in planaria suggests an ancestral association of this signaling pathway and cilia function.
Cell-Specific Information Processing in Segregating Populations of Eph Receptor Ephrin–Expressing Cells (11 December 2009)
C. Jørgensen et al.
A proteomic strategy elucidates signaling networks between cells communicating through ephrin proteins and their receptors.
Norbin Is an Endogenous Regulator of Metabotropic Glutamate Receptor 5 Signaling (11 December 2009)
H. Wang et al.
The protein Norbin regulates accumulation of a neurotransmitter receptor in mouse brain cell membranes.
GENETICS
Altered Heterochromatin Binding by a Hybrid Sterility Protein in Drosophila Sibling Species (11 December 2009)
J. J. Bayes and H. S. Malik
A male sterility protein localizes to evolutionarily dynamic loci within heterochromatin and leads to their decondensation.
Mapping Human Genetic Diversity in Asia (11 December 2009)
The HUGO Pan-Asian SNP Consortium
Genetic analyses of Asian peoples suggest that the continent was populated through a single migration event.
Stepwise Modification of a Modular Enhancer Underlies Adaptation in a Drosophila Population (18 December 2009)
M. Rebeiz et al.
A combination of new and previously existing mutations in gene regulatory sequences can drive morphological evolution.
NEUROSCIENCE/PSYCHOLOGY
GABAergic Hub Neurons Orchestrate Synchrony in Developing Hippocampal Networks (4 December 2009)
P. Bonifazi et al.
A model for the topology of brain networks incorporates a morphofunctional description of neuronal hubs.
Deletion of Atoh1 Disrupts Sonic Hedgehog Signaling in the Developing Cerebellum and Prevents Medulloblastoma (4 December 2009)
A. Flora et al.
A transcription factor regulates signaling in the developing mouse cerebellum and also influences cancer formation.
Indirect Punishment and Generosity Toward Strangers (18 December 2009)
A. Ule et al.
Frequent rewards spiced with occasional punishment are a recipe for the evolution of cooperation.
The Subtle Transmission of Race Bias via Televised Nonverbal Behavior (18 December 2009)
M. Weisbuch et al.
Nonverbal behaviors can contribute to implicit bias in intergroup attitudes.
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PLANT SCIENCE
Structural Mechanism of Abscisic Acid Binding and Signaling by Dimeric PYR1 (4 December 2009)
N. Nishimura et al.
The plant hormone responsible for drought tolerance signals by inducing conformational changes in its dimeric protein receptor.
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A Simple Cipher Governs DNA Recognition by TAL Effectors (11 December 2009)
M. J. Moscou and A. J. Bogdanove
Xanthomonas bacteria use an amino acid–based code to target effector molecules to specific DNA sequences.
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Breaking the Code of DNA Binding Specificity of TAL-Type III Effectors (11 December 2009)
J. Boch et al.
Artificial effectors with new specificities have been constructed that mimic proteins injected into plant cells by pathogens.
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MEDICINE
Positively Selected G6PD-Mahidol Mutation Reduces Plasmodium vivax Density in Southeast Asians (11 December 2009)
C. Louicharoen et al.
Positive selection acts on a hemolytic anemia - causing mutation that affects the proliferation of a blood parasite in humans.
MicroRNA-206 Delays ALS Progression and Promotes Regeneration of Neuromuscular Synapses in Mice (11 December 2009)
A. H. Williams et al.
A small noncoding RNA promotes nerve-muscle interactions in response to motor neuron injury and slows disease progression.
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MICROBIOLOGY
Bacterial Community Variation in Human Body Habitats Across Space and Time (18 December 2009)
E. K. Costello et al.
The composition of microbial communities on the human body is primarily determined by their location.
MOLECULAR BIOLOGY
The Fanconi Anemia Pathway Promotes Replication-Dependent DNA Interstrand Cross-Link Repair (18 December 2009)
P. Knipscheer et al.
Insertion of a nucleotide during the repair of a complex lesion in DNA requires tagging of a lysine residue.