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[Letters] Genes and quadrupedal locomotion in humans

Humphrey, N., Mundlos, S., Turkmen, S. — 2008-05-15

[Cell_Biology] Structural basis for tropomyosin overlap in thin (actin) filaments and the generation of a molecular swivel by troponin-T

2008-05-15

Head-to-tail polymerization of tropomyosin is crucial for its actin binding, function in actin filament assembly, and the regulation of actin-myosin...

[Genetics] MLL protects CpG clusters from methylation within the Hoxa9 gene, maintaining transcript expression

2008-05-15

Homeobox (HOX) genes play a definitive role in determination of cell fate during embryogenesis and hematopoiesis. MLL-related leukemia is coincident...

[Biophysics] Paired {beta}-sheet structure of an A{beta}(1-40) amyloid fibril revealed by electron microscopy

Sachse, C., Fandrich, M., Grigorieff, N. — 2008-05-15

Alzheimer's disease is a neurodegenerative disorder that is characterized by the cerebral deposition of amyloid fibrils formed by Aβ peptide....

[Commentary] Integrins step up the pace of cell migration through polyamines and potassium channels

Vandenberg, C. A. — 2008-05-14

[Letters] Reply to Belmaker et al.: GSK3{beta} haploinsufficiency results in lithium-like effects in the forced-swim test

2008-05-14

[Cell_Biology] Chemicals that modulate stem cell differentiation

2008-05-14

Important cellular processes such as cell fate are likely to be controlled by an elaborate orchestration of multiple signaling pathways,...

[Applied_Biological_Sciences] Lack of aldose 1-epimerase in Hypocrea jecorina (anamorph Trichoderma reesei): A key to cellulase gene expression on lactose

Fekete, E., Seiboth, B., Kubicek, C. P., Szentirmai, A., Karaffa, L. — 2008-05-14

The heterodisaccharide lactose (1,4-O-β-d-galactopyranosyl-d-glucose) induces cellulase formation in the ascomycete Hypocrea jecorina (= Trichoderma reesei). Lactose assimilation is slow, and...

[Neuroscience] Estradiol modulation of phenylephrine-induced excitatory responses in ventromedial hypothalamic neurons of female rats

2008-05-14

Estrogens act within the ventromedial nucleus of the hypothalamus (VMN) to facilitate lordosis behavior. Estradiol treatment in vivo induces _1b-adrenoreceptor...

[Cell_Biology] Chaperone-dependent amyloid assembly protects cells from prion toxicity

2008-05-14

Protein conformational diseases are associated with the aberrant accumulation of amyloid protein aggregates, but whether amyloid formation is cytotoxic or...

[Neuroscience] Retromer deficiency observed in Alzheimer's disease causes hippocampal dysfunction, neurodegeneration, and A{beta} accumulation

2008-05-14

Although deficiencies in the retromer sorting pathway have been linked to late-onset Alzheimer's disease, whether these deficiencies underlie the disease...

[Immunology] Distinct roles for IL-13 and IL-4 via IL-13 receptor {alpha}1 and the type II IL-4 receptor in asthma pathogenesis

Munitz, A., Brandt, E. B., Mingler, M., Finkelman, F. D., Rothenberg, M. E. — 2008-05-14

IL-13 and IL-4 are central T helper 2 (Th2) cytokines in the immune system and potent activators of inflammatory responses...

[Immunology] Alternative translation of osteopontin generates intracellular and secreted isoforms that mediate distinct biological activities in dendritic cells

Shinohara, M. L., Kim, H.-J., Kim, J.-H., Garcia, V. A., Cantor, H. — 2008-05-14

Osteopontin (Opn) contributes to diverse biological processes that include immune responses, vascularization, and bone formation. Until recently, studies describing the...

[Biochemistry] Direct and selective elimination of specific prions and amyloids by 4,5-dianilinophthalimide and analogs

2008-05-14

Mechanisms to safely eliminate amyloids and preamyloid oligomers associated with many devastating diseases are urgently needed. Biophysical principles dictate that...

[Biophysics] Protein folding: Independent unrelated pathways or predetermined pathway with optional errors

Bedard, S., Krishna, M. M. G., Mayne, L., Englander, S. W. — 2008-05-14

The observation of heterogeneous protein folding kinetics has been widely interpreted in terms of multiple independent unrelated pathways (IUP model),...

[Medical_Sciences] Activin B receptor ALK7 is a negative regulator of pancreatic {beta}-cell function

2008-05-14

All major cell types in pancreatic islets express the transforming growth factor (TGF)-β superfamily receptor ALK7, but the physiological function...

[Medical_Sciences] Growth/differentiation factor 3 signals through ALK7 and regulates accumulation of adipose tissue and diet-induced obesity

Andersson, O., Korach-Andre, M., Reissmann, E., Ibanez, C. F., Bertolino, P. — 2008-05-14

Growth/differentiation factor 3 (GDF3) is highly expressed in adipose tissue, and previous overexpression experiments in mice have suggested that it...

[Applied_Biological_Sciences] A gastrolith protein serving a dual role in the formation of an amorphous mineral containing extracellular matrix

2008-05-14

Despite the proclamation of Lowenstam and Weiner that crustaceans are the "champions of mineral mobilization and deposition of the animal...

[Physics] Field-induced quantum critical route to a Fermi liquid in high-temperature superconductors

2008-05-14

In high-transition-temperature (T_c) superconductivity, charge doping is a natural tuning parameter that takes copper oxides from the antiferromagnet to the...

[Geology] High-pressure synthesis of the cubic perovskite BaRuO3 and evolution of ferromagnetism in ARuO3 (A = Ca, Sr, Ba) ruthenates

2008-05-14

The cubic perovskite BaRuO₃ has been synthesized under 18 GPa at 1,000°C. Rietveld refinement indicates that the new compound has...

[Biophysics] Signal processing by the HOG MAP kinase pathway

Hersen, P., McClean, M. N., Mahadevan, L., Ramanathan, S. — 2008-05-14

Signaling pathways relay information about changes in the external environment so that cells can respond appropriately. How much information a...

[Medical_Sciences] Specific inhibitors of the protein tyrosine phosphatase Shp2 identified by high-throughput docking

2008-05-14

The protein tyrosine phosphatase Shp2 is a positive regulator of growth factor signaling. Gain-of-function mutations in several types of leukemia...

[Biochemistry] Superoxide dismutase 1 (SOD1) is essential for H2O2-mediated oxidation and inactivation of phosphatases in growth factor signaling

2008-05-14

Superoxide dismutase 1 (SOD1) is an abundant copper/zinc enzyme found in the cytoplasm that converts superoxide into hydrogen peroxide and...

[Cell_Biology] The {alpha}9{beta}1 integrin enhances cell migration by polyamine-mediated modulation of an inward-rectifier potassium channel

deHart, G. W., Jin, T., McCloskey, D. E., Pegg, A. E., Sheppard, D. — 2008-05-14

The 9β1 integrin accelerates cell migration through binding of spermidine/spermine acetyltransferase (SSAT) to the 9 cytoplasmic domain. We now show...

[Developmental_Biology] Four-dimensional analysis of vascularization during primary development of an organ, the gonad

Coveney, D., Cool, J., Oliver, T., Capel, B. — 2008-05-14

Time-lapse microscopy has advanced our understanding of yolk sac and early embryonic vascularization. However, it has been difficult to assess...

[Chemistry] Atomic interactions of neonicotinoid agonists with AChBP: Molecular recognition of the distinctive electronegative pharmacophore

2008-05-13

Acetylcholine-binding proteins (AChBPs) from mollusks are suitable structural and functional surrogates of the nicotinic acetylcholine receptors when combined with transmembrane...

[Neuroscience] Hypoxia and the HIF-1 transcriptional pathway reorganize a neuronal circuit for oxygen-dependent behavior in Caenorhabditis elegans

Chang, A. J., Bargmann, C. I. — 2008-05-13

Rapid behavioral responses to oxygen are generated by specialized sensory neurons that sense hypoxia and hyperoxia. On a slower time...

[Biochemistry] A rationally engineered misacylating aminoacyl-tRNA synthetase

Bullock, T. L., Rodriguez-Hernandez, A., Corigliano, E. M., Perona, J. J. — 2008-05-13

Information transfer from nucleic acid to protein is mediated by aminoacyl-tRNA synthetases, which catalyze the specific pairings of amino acids...

[Biophysics] Prediction of membrane-protein topology from first principles

Bernsel, A., Viklund, H., Falk, J., Lindahl, E., Heijne, G. v., Elofsson, A. — 2008-05-13

The current best membrane-protein topology-prediction methods are typically based on sequence statistics and contain hundreds of parameters that are optimized...

[Neuroscience] Electrical microstimulation thresholds for behavioral detection and saccades in monkey frontal eye fields

Murphey, D. K., Maunsell, J. H. R. — 2008-05-13

The frontal eye field (FEF) is involved in the transformation of visual signals into saccadic eye movements. Although it is...

[Biochemistry] EB1 promotes Aurora-B kinase activity through blocking its inactivation by protein phosphatase 2A

2008-05-13

EB1 (end-binding protein 1) is a key player in the regulation of microtubule dynamics. In concert with its binding partners,...

[Neuroscience] Cerebellar-dependent motor learning is based on pruning a Purkinje cell population response

Catz, N., Dicke, P. W., Thier, P. — 2008-05-13

The improvement of motor behavior, based on experience, is a form of learning that is critically dependent on the cerebellum....

[Commentary] A VAST staging area for regulatory proteins

Mitchell, A. P. — 2008-05-12

[Applied_Biological_Sciences] Cuticular hydrocarbon analysis of an awake behaving fly using direct analysis in real-time time-of-flight mass spectrometry

Yew, J. Y., Cody, R. B., Kravitz, E. A. — 2008-05-12

In mammals and insects, pheromones strongly influence social behaviors such as aggression and mate recognition. In Drosophila melanogaster, pheromones in...

[Medical_Sciences] Common SNP in pre-miR-146a decreases mature miR expression and predisposes to papillary thyroid carcinoma

2008-05-12

Although papillary thyroid carcinoma (PTC) displays strong heritability, no predisposing germ-line mutations have been found. We show that a common...

[Neuroscience] Reversal of opiate-induced apoptosis by human recombinant growth hormone in murine foetus primary hippocampal neuronal cell cultures

Svensson, A.-L., Bucht, N., Hallberg, M., Nyberg, F. — 2008-05-12

Previous studies have shown that chronic opiates may inhibit cell growth and trigger apoptosis leading to impaired cognitive capabilities in...

[Letters] Role of GSK3{beta} in behavioral abnormalities induced by serotonin deficiency

Belmaker, R. H., Agam, G., Bersudsky, Y. — 2008-05-12

[Medical_Sciences] Fecal transmission of AA amyloidosis in the cheetah contributes to high incidence of disease

2008-05-12

AA amyloidosis is one of the principal causes of morbidity and mortality in captive cheetahs (Acinonyx jubatus), which are in...

[Neuroscience] Hyperpolarization-activated graded persistent activity in the prefrontal cortex

Winograd, M., Destexhe, A., Sanchez-Vives, M. V. — 2008-05-12

We describe a phenomenon of hyperpolarization-activated graded persistent activity (HAGPA) in prefrontal cortex neurons. Successive hyperpolarizing pulses induced increasingly higher...

[Medical_Sciences] Comprehensive screening for antigens overexpressed on carcinomas via isolation of human mAbs that may be therapeutic

2008-05-12

Although several murine mAbs that have been humanized became useful therapeutic agents against a few malignancies, therapeutic Abs are not...

[Biophysics] Prediction of the tissue-specificity of selective estrogen receptor modulators by using a single biochemical method

2008-05-12

Here, we demonstrate that a single biochemical assay is able to predict the tissue-selective pharmacology of an array of selective...

[Biophysics] Colloquium Paper: A DNA-based nanomechanical device with three robust states

Chakraborty, B., Sha, R., Seeman, N. C. — 2008-05-12

DNA has been used to build a variety of devices, ranging from those that are controlled by DNA structural transitions...

[Evolution] On the coevolution of Ediacaran oceans and animals

Shen, Y., Zhang, T., Hoffman, P. F. — 2008-05-09

Fe speciation and S-isotope of pyrite data from the terminal Proterozoic Sheepbed Formation in Canada and Doushantuo Formation in China...

[Environmental_Sciences] Involvement of testicular growth factors in fetal Leydig cell aggregation after exposure to phthalate in utero

2008-05-09

Exposures to di-(2-ethylhexyl) phthalate (DEHP) have been shown to be associated with decreased adult testosterone (T) levels and increased Leydig...

[Plant_Biology] Modulation of brassinosteroid-regulated gene expression by jumonji domain-containing proteins ELF6 and REF6 in Arabidopsis

Yu, X., Li, L., Li, L., Guo, M., Chory, J., Yin, Y. — 2008-05-08

Plant steroid hormones, brassinosteroids (BRs), are of great importance for plant growth and development. BRs signal through a cell surface...

[Evolution] Alternative splicing: A missing piece in the puzzle of intron gain

Tarrio, R., Ayala, F. J., Rodriguez-Trelles, F. — 2008-05-07

Spliceosomal introns, a hallmark of eukaryotic gene organization, were an unexpected discovery. After three decades, crucial issues such as when...

[Medical_Sciences] Leptin responsiveness restored by amylin agonism in diet-induced obesity: Evidence from nonclinical and clinical studies

2008-05-06

Body weight is regulated by complex neurohormonal interactions between endocrine signals of long-term adiposity (e.g., leptin, a hypothalamic signal) and...

[Social_Sciences] Sociality, selection, and survival: Simulated evolution of mortality with intergenerational transfers and food sharing

Lee, R. — 2008-05-05

Why do humans survive so long past reproductive age, and why does juvenile mortality decline after birth, both contrary to...

[Cell_Biology] Nuclear translocation of Gln3 in response to nutrient signals requires Golgi-to-endosome trafficking in Saccharomyces cerevisiae

Puria, R., Zurita-Martinez, S. A., Cardenas, M. E. — 2008-04-28

The yeast Saccharomyces cerevisiae has developed specialized mechanisms that enable growth on suboptimal nitrogen sources. Exposure of yeast cells to...

[Geophysics] A liquid-crystal model for friction

Cheng, C. H. A., Kellogg, L. H., Shkoller, S., Turcotte, D. L. — 2008-04-16

Rate-and-state friction is an empirical approach to the behavior of a frictional surface. We use a nematic liquid crystal in...

[Biophysics] Simulation of Top7-CFr: A transient helix extension guides folding

Mohanty, S., Meinke, J. H., Zimmermann, O., Hansmann, U. H. E. — 2008-04-11

Protein structures often feature β-sheets in which adjacent β-strands have large sequence separation. How the folding process orchestrates the formation...

[Biochemistry] Oxygen-regulated isoforms of cytochrome c oxidase have differential effects on its nitric oxide production and on hypoxic signaling

Castello, P. R., Woo, D. K., Ball, K., Wojcik, J., Liu, L., Poyton, R. O. — 2008-04-03

Recently, it has been reported that mitochondria possess a novel pathway for nitric oxide (NO) synthesis. This pathway is induced...

[Medical_Sciences] Starvation-dependent differential stress resistance protects normal but not cancer cells against high-dose chemotherapy

2008-03-31

Strategies to treat cancer have focused primarily on the killing of tumor cells. Here, we describe a differential stress resistance...

[Biophysics] Microtubule curvatures under perpendicular electric forces reveal a low persistence length

Van den Heuvel, M. G. L., de Graaff, M. P., Dekker, C. — 2008-03-21

The mechanics of microtubules, cylindrical protein filaments that constitute the cytoskeleton, have been well characterized on long length scales. Here,...

[Biophysics] Bidirectional membrane tube dynamics driven by nonprocessive motors

Shaklee, P. M., Idema, T., Koster, G., Storm, C., Schmidt, T., Dogterom, M. — 2008-03-11

In cells, membrane tubes are extracted by molecular motors. Although individual motors cannot provide enough force to pull a tube,...

[Applied_Mathematics] Optimal partition and effective dynamics of complex networks

E, W., Li, T., Vanden-Eijnden, E. — 2008-02-28

Given a large and complex network, we would like to find the best partition of this network into a small...

[Biochemistry] Quantifying changes in the thiol redox proteome upon oxidative stress in vivo

2008-02-14

Antimicrobial levels of reactive oxygen species (ROS) are produced by the mammalian host defense to kill invading bacteria and limit...

[Biochemistry] Probing concerted proton-electron transfer in phenol-imidazoles

Markle, T. F., Rhile, I. J., DiPasquale, A. G., Mayer, J. M. — 2008-01-22

A series of seven substituted 4,6-di-tert-butyl-2-(4,5-diarylimidazolyl)-phenols have been prepared and characterized, along with two related benzimidazole compounds. X-ray crystal structures...

[Biochemistry] X-ray absorption spectroscopic characterization of a cytochrome P450 compound II derivative

2008-01-03

The cytochrome P450 enzyme CYP119, its compound II derivative, and its nitrosyl complex were studied by iron K-edge x-ray absorption...

[Biochemistry] Substrate specificity and redox potential of AhpC, a bacterial peroxiredoxin

Parsonage, D., Karplus, P. A., Poole, L. B. — 2007-12-28

Typical 2-Cys peroxiredoxins (Prxs) are ubiquitous peroxidases that are involved in peroxide scavenging and/or the regulation of peroxide signaling in...