Editors' Choice

Science  05 Sep 2014:
Vol. 345, Issue 6201, pp. 1132
  1. Cell Biology

    A long noncoding RNA helps cells divide

    1. Guy Riddihough

    Centromeres help chromosomes segregate


    When cells divide, they distribute chromosomes to the daughter cells. Centromeres—specialized regions of chromosomes—ensure that the chromosomes segregate properly during the process. Quénet and Dalal find that an RNA transcribed from human centromeric DNA recruits proteins that form this specialized region. Unlike many RNAs, the centromeric RNA does not encode a protein, but instead binds to two proteins, CENP-A and HJURP, that help “package” DNA and proteins together so that the centromere can function properly.

    eLife 10.7554/eLife.03254 (2014).

  2. Signal Transduction

    A drug's two-part way to block dopamine

    1. Valda Vinson

    The dopamine receptor DR2 is a potential target for antipsychotic drugs. A new study reports an unusual mechanism of action for a small molecule that targets DR2. The core structure of the molecule, called SB26952, suggests it would bind to the same place as dopamine (the orthosteric site). Instead, however, it acts like an allosteric inhibitor—that is, an inhibitor that binds to a secondary (allosteric) site on DR2, preventing dopamine from binding to the orthosteric site. Campbell et al. now report that SB26952 binds to both the orthosteric and allosteric sites in one DR2 molecule, which is part of a pair. This inhibits dopamine binding to the orthosteric site of the second DR2 molecule.

    Nat. Chem. Biol. 10.1038/nchembio.1593 (2014).

  3. Climate Change

    Anthropogenic de-icing on a grand scale

    1. H. Jesse Smith

    The Greenland ice sheet has been losing mass at increasingly rapid rates over the past several decades, as expected due to climate warming, but it is difficult to tell whether that loss is a result of human forcing. Fyke et al. examine how that can be done, using a coupled ice sheet/climate model. They find that anthropogenic warming should produce a bimodal pattern of melting between the interior and the coast and suggest that such a pattern is already emerging. They also suggest that a well-studied location, the Greenland Ice Sheet summit region, may be an ideal place to monitor the pace of climate change.

    Geophys. Res. Lett. 10.1002/2014GL060735 (2014).

  4. Plant Science

    Tolerating aluminum

    1. Pamela J. Hines

    Harvesting sorghum in West Africa


    Sorghum bicolor can tolerate hot and dry conditions, which makes it an important grain in West Africa. But low phosphorus and high aluminum concentrations in soil there impede its growth. Leiser et al. studied sorghum varieties in West Africa and discovered a region in the sorghum genome that allowed plants to tolerate both aluminum toxicity and low amounts of phosphorus. The authors hypothesized that aluminum toxicity activates a key gene that may have the felicitous side effect of helping the plant use phosphorus more efficiently.

    BMC Plant Biol. 14, 206 (2014).

  5. Drug Delivery

    Layers of ways to control drug release

    1. Marc S. Lavine

    When people overuse antibiotics, microbes can develop resistance. In a setting such as a hospital, where bacteria may accumulate on the surfaces of medical devices, it is important to be able to administer antibiotics on demand, without overusing them. Zhuk et al. show how films made from tannic acid and one of three antibiotics can decrease antibiotic use. They created a film that does not release any antibiotic at a pH of 7.4, but which does release it when it is exposed to Staphylococcus epidermidis or Escherichia coli, which acidify their local environments. The release depends on the antibiotic used, the film fabrication method, and the overall thickness of the film, providing multiple ways to control antibiotic delivery.

    ACS Nano 10.1021/nn500674g (2014).

  6. Quantum Mechanics

    Quantum imaging of Schrödinger's cat

    1. Angela Colmone

    These images of a cardboard cutout of a cat were made with light that never touched it. Barreto Lemos et al. began with two identical photons, one shining through the object and the other going by it, and made them overlap and interfere. Each photon is also created with a photon of shorter wavelength; they share a quantum connection called entanglement which allows the researchers to make the shorter-wavelength photons also interfere. The pair can then go one way or the other when they hit a beam splitter. Thus, by scanning the longer-wavelength photon pairs over the object, the team can construct two images—one for each direction out of a beam splitter—using the shorter-wavelength photons that never actually touched the object. The technique makes it possible to image an object using a color of light that would normally pass through it.

    Nature 10.1038/nature13586 (2014).

  7. CO2 Reduction

    An edgy way to transform carbon dioxide

    1. Jake Yeston

    Plants are adept at turning CO2 into organic material. Unfortunately, humans have outpaced them in the other direction, releasing substantially more CO2 into the atmosphere than natural photosynthesis can concurrently consume. Although chemists are late entrants to the CO2 conversion game, they're now redoubling their effort in the face of climate change. Asadi et al. present a cost-effective catalyst for electrochemical reduction of CO2 to CO, an important feedstock for a wide range of commodity chemicals. The catalyst, molybdenum disulfide, is highly active at its edges and ultimately less expensive than the gold and silver previously investigated for this purpose.

    Nat. Commun. 10.1038/ncomms5470 (2014).

  8. Human Genetics

    When genetic diversity hurts the kids

    1. Laura M. Zahn

    Although we think of the genome as fixed, errors in DNA replication and recombination can cause changes. As the organism develops, individual nucleotides may mutate, or genetic material may duplicate or be deleted. Such “somatic mosaicism” means that different cells and tissues in the body may have different genomes. To determine whether this affects human disease, Campbell et al. took blood samples from 100 families with children who have genetic disorders. They found that approximately 4% of the parents (who were all healthy) exhibited somatic mosaicism, which suggests that the affected children inherited the mutation from a mosaic parent. These results suggest that somatic mosaicism is probably more common than previously thought and affects human health.

    Am. J. of Hum. Genet. 10.1016/j.ajhg.2014.07.003 (2014).