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Protection of CiA/GliA by CK1 [Developmental Biology]

PNAS Early Edition Articles - Mon, 12/15/2014 - 14:05
Hedgehog (Hh) signaling governs many developmental processes by regulating the balance between the repressor (CiR/GliR) and activator (CiA/GliA) forms of Cubitus interruptus (Ci)/glioma-associated oncogene homolog (Gli) transcription factors. Although much is known about how CiR/GliR is controlled, the regulation of CiA/GliA remains poorly understood. Here we demonstrate that Casein kinase...

Preventing cognitive decline with spine clustering [Neuroscience]

PNAS Early Edition Articles - Mon, 12/15/2014 - 14:05
The dementia of Alzheimer’s disease (AD) results primarily from degeneration of neurons that furnish glutamatergic corticocortical connections that subserve cognition. Although neuron death is minimal in the absence of AD, age-related cognitive decline does occur in animals as well as humans, and it decreases quality of life for elderly people....

Global language network [Applied Physical Sciences]

PNAS Early Edition Articles - Mon, 12/15/2014 - 14:05
Languages vary enormously in global importance because of historical, demographic, political, and technological forces. However, beyond simple measures of population and economic power, there has been no rigorous quantitative way to define the global influence of languages. Here we use the structure of the networks connecting multilingual speakers and translated...

Nonrandomness is strongest in seedlings [Ecology]

PNAS Early Edition Articles - Mon, 12/15/2014 - 14:05
A variety of ecological processes influence diversity and species composition in natural communities. Most of these processes, whether abiotic or biotic, differentially filter individuals from birth to death, thereby altering species’ relative abundances. Nonrandom outcomes could accrue throughout ontogeny, or the processes that generate them could be particularly influential at...

Network properties of the mouse connectome [Neuroscience]

PNAS Early Edition Articles - Mon, 12/15/2014 - 14:05
Noninvasive functional imaging holds great promise for serving as a translational bridge between human and animal models of various neurological and psychiatric disorders. However, despite a depth of knowledge of the cellular and molecular underpinnings of atypical processes in mouse models, little is known about the large-scale functional architecture measured...

Role of self-interest in elite bargaining [Political Sciences]

PNAS Early Edition Articles - Mon, 12/15/2014 - 14:05
One of the best-known and most replicated laboratory results in behavioral economics is that bargainers frequently reject low offers, even when it harms their material self-interest. This finding could have important implications for international negotiations on many problems facing humanity today, because models of international bargaining assume exactly the opposite:...

MyBP-C controls filament structure in heart muscle [Physiology]

PNAS Early Edition Articles - Mon, 12/15/2014 - 14:05
Myosin binding protein-C (MyBP-C) is a key regulatory protein in heart muscle, and mutations in the MYBPC3 gene are frequently associated with cardiomyopathy. However, the mechanism of action of MyBP-C remains poorly understood, and both activating and inhibitory effects of MyBP-C on contractility have been reported. To clarify the function...

Molecular mechanism of ERCC6 autoregulation [Biochemistry]

PNAS Early Edition Articles - Mon, 12/15/2014 - 14:05
CSB/ERCC6 (Cockayne syndrome B protein/excision repair cross-complementation group 6), a member of a subfamily of SWI2/SNF2 (SWItch/sucrose nonfermentable)-related chromatin remodelers, plays crucial roles in gene expression and the maintenance of genome integrity. Here, we report the mechanism of the autoregulation of Rhp26, which is the homolog of CSB/ERCC6 in Schizosaccharomyces...

Wolbachia encodes small noncoding RNAs [Microbiology]

PNAS Early Edition Articles - Mon, 12/15/2014 - 14:05
In prokaryotes, small noncoding RNAs (snRNAs) of 50–500 nt are produced that are important in bacterial virulence and response to environmental stimuli. Here, we identified and characterized snRNAs from the endosymbiotic bacteria, Wolbachia, which are widespread in invertebrates and cause reproductive manipulations. Most importantly, some strains of Wolbachia inhibit replication...

S-nitroso-CoA reductases [Biochemistry]

PNAS Early Edition Articles - Mon, 12/15/2014 - 14:05
Coenzyme A (CoA) mediates thiol-based acyl-group transfer (acetylation and palmitoylation). However, a role for CoA in the thiol-based transfer of NO groups (S-nitrosylation) has not been considered. Here we describe protein S-nitrosylation in yeast (heretofore unknown) that is mediated by S-nitroso-CoA (SNO-CoA). We identify a specific SNO-CoA reductase encoded by...

Targeting efforts to reduce Gulf of Mexico hypoxia [Environmental Sciences]

PNAS Early Edition Articles - Mon, 12/15/2014 - 14:05
A seasonally occurring summer hypoxic (low oxygen) zone in the northern Gulf of Mexico is the second largest in the world. Reductions in nutrients from agricultural cropland in its watershed are needed to reduce the hypoxic zone size to the national policy goal of 5,000 km2 (as a 5-y running...

PTEN signaling is essential for male fertility [Developmental Biology]

PNAS Early Edition Articles - Mon, 12/15/2014 - 14:05
Without a fully developed initial segment, the most proximal region of the epididymis, male infertility results. Therefore, it is important to understand the development and regulation of this crucial region. In addition to distinctively high activity levels of the components of the ERK pathway, which are essential for initial-segment differentiation,...

Structure and interactions of Aux/IAA17 [Biophysics and Computational Biology]

PNAS Early Edition Articles - Mon, 12/15/2014 - 14:05
Auxin is the central hormone that regulates plant growth and organ development. Transcriptional regulation by auxin is mediated by the auxin response factor (ARF) and the repressor, AUX/IAA. Aux/IAA associates with ARF via domain III−IV for transcriptional repression that is reversed by auxin-induced Aux/IAA degradation. It has been known that...

Structure of a pantothenate ECF transporter [Biochemistry]

PNAS Early Edition Articles - Mon, 12/15/2014 - 14:05
Energy-coupling factor (ECF) transporters are a unique group of ATP-binding cassette (ABC) transporters responsible for micronutrient uptake from the environment. Each ECF transporter is composed of an S component (or EcfS protein) and T/A/A′ components (or EcfT/A/A′ proteins; ECF module). Among the group II ECF transporters, several EcfS proteins share...

Watch: Marc Morano & Walt Cunningham in contentious debate on UN Climate TV at Lima Summit

Climate Depot - Mon, 12/15/2014 - 13:00
Via: http://climatechange-tv.rtcc.org/2014/12/15/cop20-marc-morano-of-cfact-and-walt-cunningham/ UN Climate TV Description of Debate: Marc Morano, Walt Cunningham , CFACT From Lima: COP20 UN Climate Change Conference 2014 in December 2014 COP20 (11/12/14) – Marc Morano of CFACT and Walt Cunningham talk to RTCC about their opinion that human activity cannot alter the climate. They feel that global efforts to tackle climate climate change, particularly in [...]

Kilopower for space exploration

World Nuclear News - Mon, 12/15/2014 - 11:03
Nasa's Glenn Center has called on the services of the US National Nuclear Security Administration (NNSA) to support its mission to develop the Kilopower project, using uranium-fuelled Stirling engines in space missions.
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