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Press release from Nature and the Nature Research Journals dated 7 September

September 08, 2003

NATURE
(http://www.nature.com/nature)

[1] Uric acid signals danger

DOI: 10.1038/nature01991 (http://dx.doi.org/10.1038/nature01991)

Uric acid may signal the immune system to warn it of impending danger, according to a paper published online by Nature this week. The research provides a molecular link between cell injury and immunity, and may have implications for vaccines, autoimmunity and inflammation.
        Cells normally contain uric acid. Now Kenneth L. Rock and colleagues report that when cells are injured, their levels of uric acid go up. When released from dying cells, it stimulates bone-marrow-derived dendritic cells to mature so that they can present foreign particles to the immune system and help trigger an immune response.

        Uric acid may also help boost the effects of vaccines in humans, the researchers speculate. So far, only one compound, alum, has been approved for use as an adjuvant. Uric acid may represent a second possibility.

Author contact:
Kenneth Rock (University of Massachusetts Medical School, Worcester, MA, USA)
Tel: +1 508 856 2521; E-mail: Kenneth.rock@umassmed.edu

NATURE BIOTECHNOLOGY
(http://www.nature.com/naturebiotechnology)

[2] Bacterial batteries
DOI: 10.1038/nbt867 (http://dx.doi.org/10.1038/nbt867)

Scientists have developed a highly efficient microbial fuel cell, a sort of 'bacterial battery' that produces electricity consistently and over long periods of time. Taking advantage of the unique characteristics of a bacterium, Rhodoferax ferrireducens, previously isolated from marine sediments, Swades Chaudhuri and Derek Lovley report in the October issue of Nature Biotechnology on the power producing capabilities of a fuel cell harboring this organism. Because R. ferrireducens is capable of transferring electrons generated while feeding on simple sugars such as glucose (the main form of sugar in the environment), fructose (abundantly found in fruits), sucrose (present in sugar cane and sugar beet) and xylose (a constituent of wood and straw) directly to an electrode, the efficiency in converting the energy contained in these sugars to electricity is over 80%. Previously, fuel cells achieving up to 50% efficiency in energy conversion had been described, but these were dependent on the use of unstable electron transfer mediators, and thus expensive and not suitable for long-term electricity generation.
Given the wide range of substrates Chaudhuri and Lovley's fuel cell can be powered with, the use of microbial fuel cells to produce energy from sugar-containing waste materials is now one step closer to being realized.

Author contact:
Derek R. Lovley (University of Massachusetts, Amherst, MA, USA)
Tel: +1 413 545 9651; E-mail: dlovley@microbio.umass.edu

Other papers from Nature Biotechnology be published online at the same time and with the same embargo:
[3] Phenotypic alteration of eukaryotic cells using randomized libraries of artificial transcription factors (DOI: 10.1038/nbt868) (http://dx.doi.org/10.1038/nbt868)

[4] Large-scale genotyping of complex DNA
(DOI: 10.1038/nbt869) (http://dx.doi.org/10.1038/nbt869)

NATURE NEUROSCIENCE
(http://www.nature.com/natureneuroscience)

[5] Timing sleep and wakefulness

DOI: 10.1038/nn1122 (http://dx.doi.org/10.1038/nn1122)

A circadian clock within the brain ensures that we sleep at night and are awake during the day. But as anyone who has stayed up all night and fallen into a deep sleep the next morning knows, the timing of sleep also depends on the need for sleep. Now a paper in the October issue of Nature Neuroscience reports that sleep homeostatic processes, which cause the urge to sleep to depend on prior amounts of sleep or wakefulness, influence the circadian clock.

        Johanna Meijer and colleagues monitored the vigilance state of rats by recording their brain (EEG) and muscle (EMG) signals. At the same time, the experimenters recorded neuronal activity within a brain region called the suprachiasmatic nucleus (SCN) to monitor the output of the circadian clock. Driven by cycles of gene transcription and translation, activity in the SCN normally oscillates with day and night cycles. They found a clear correlation between vigilance states and activity in the SCN. Furthermore, by using sleep deprivation experiments, they tested for a casual relationship. Indeed, during sleep deprivation, neuronal activity in the SCN failed to show expected changes in electrical activity for the time of day, demonstrating that activity in the SCN is determined not only by the molecular machinery of the circadian clock, but also by sleep need. A next step will be to determine how changes in need for sleep are communicated to the SCN at the molecular level.
        
Author contact:
Johanna Meijer (University of Leiden, The Netherlands)
Tel: +31 71 527 67 15; E-mail: J.H.Meijer@lumc.nl

Additional contact for comment on paper:
Christopher Colwell (University of California at Los Angeles, Los Angeles, CA, USA.)
Tel: +1 310 206 3973; E-mail: ccolwell@mednet.ucla.edu

Other papers from Nature Neuroscience to be published online at the same time and with the same embargo:

[6] Expert face processing requires visual input to the right hemisphere during infancy
(DOI: 10.1038/nn1121) (http://dx.doi.org/10.1038/nn1121)

**************************
Items from other Nature journals to be published online at the same time and with the same embargo:

NATURE MATERIALS (http://www.nature.com/naturematerials)

[7] Surface-stress-induced phase transformation in metal nanowires
(DOI: 10.1038/nmat977) (http://dx.doi.org/10.1038/nmat977)

[8] Stable and controlled amphoteric doping by encapsulation of organic molecules inside carbon nanotubes
(DOI: 10.1038/nmat976) (http://dx.doi.org/10.1038/nmat976)

NATURE MEDICINE (http://www.nature.com/naturemedicine)

[9] Pharmacologic inactivation of kinase suppressor of ras-1 abrogates Ras-mediated pancreatic cancer
(DOI: 10.1038/nm927) (http://dx.doi.org/10.1038/nm927)

[10] Genetic deficiency in Pparg does not alter development of experimental prostate cancer
(DOI: 10.1038/nm928) (http://dx.doi.org/10.1038/nm928)

[11] Lipoprotein receptor-mediated induction of matrix metalloproteinase by tissue plasminogen activator
(DOI: 10.1038/nm926) (http://dx.doi.org/10.1038/nm926)

NATURE GENETICS (http://www.nature.com/naturegenetics)

[12] The genetic architecture of odor-guided behavior in Drosophila: epistasis and the transcriptome
(DOI: 10.1038/ng1240) (http://dx.doi.org/10.1038/ng1240)

[13] Mutations in NHLRC1 cause progressive myoclonus epilepsy
(DOI: 10.1038/ng1238) (http://dx.doi.org/10.1038/ng1238)

[14] No association of germline alteration of MSR1 with prostate cancer risk
(DOI: 10.1038/ng1239) (http://dx.doi.org/10.1038/ng1239)

NATURE IMMUNOLOGY (http://www.nature.com/natureimmunology)

[15] Human uracil-DNA glycosylase deficiency associated with profoundly impaired immunoglobulin class switch recombination
(DOI: 10.1038/ni974) (http://dx.doi.org/10.1038/ni974)

[16] Regulation of macrophage and neutrophil cell fate by the PU.1:C/EBPalpha ratio and granulocyte colony-stimulating factor
(DOI: 10.1038/ni973) (http://dx.doi.org/10.1038/ni973)

NATURE STRUCTURAL BIOLOGY (http://www.nature.com/naturestructuralbiology)

[17] The ligand-binding face of the semaphorins revealed by the high-resolution crystal structure of SEMA4D
(DOI: 10.1038/nsb977) (http://dx.doi.org/10.1038/nsb977)

[18] Similar modes of polypeptide recognition by export chaperones in flagellar biosynthesis and type III secretion
(DOI: 10.1038/nsb982) (http://dx.doi.org/10.1038/nsb982)

[19] All-trans retinoic acid is a ligand for the orphan nuclear receptor RORbeta
(DOI: 10.1038/nsb979) (http://dx.doi.org/10.1038/nsb979)

Nature Publishing Group Reference