Editors' Choice

Science  05 Oct 2018:
Vol. 362, Issue 6410, pp. 42
  1. Physiology

    RANKL in bone homeostasis

    1. L. Bryan Ray

    Osteoporosis reduces bone density because of imbalances in signaling feedbacks.

    PHOTO: ALAN BOYDE/VISUALS UNLIMITED, INC.

    Synthesis and breakdown of bone are tightly coupled to preserve skeletal function. Ikebuchi et al. show that signaling via a transmembrane receptor protein called receptor activator of nuclear factor–kappa B (RANK) and its ligand, RANKL, is involved in both processes. RANKL is released by bone-forming cells known as osteoblasts and stimulates RANK on the surface of stem cells to form osteoclasts, which are cells that mediate bone resorption. The same pair of proteins can also signal in reverse. In this case, RANK is released from osteoclasts in vesicles, and clusters of membrane-bound RANK activate signaling by RANKL molecules on the surface of osteoblasts to promote bone formation. Separating these two signals could prove beneficial to combat the excessive bone resorption that occurs during osteoporosis.

    Nature 561, 195 (2018).

  2. Genomics

    Evolving risks to personality

    1. Laura M. Zahn

    The origin of the uniquely large and complex human brain has been shrouded in mystery. To identify genetic changes that may underlie human evolution, Sato and Kawata examined human-specific genetic changes associated with neuropsychiatric disease and identified selection for variants in three genes. Interestingly, one variant of the SLC18A1 gene, which encodes a neurotransmitter, arose at the time humans migrated out of Africa. It appears to be under balancing selection in some populations, which has resulted in two variants in most non-African populations. This variant is linked with anxiety, but it is not yet understood what conditions favor its selection.

    Evol. Lett. 2, 499 (2018).

  3. Sociology

    Joke theft and comedians' authenticity

    1. Tage S. Rai

    Joke theft among comedians is difficult to discern because jokes are rarely identical and may be discovered independently of each other. To determine how people adjudicate instances of joke theft, Reilly conducted 4 years of participant observation and interviews among stand-up comics in Los Angeles to examine norms surrounding joke theft. He found that accusations of joke theft are driven less by joke similarity and more by a comedian's reputation, authenticity, and past success. Comedians perceived as being more successful than they deserve to be are more vulnerable to accusations of joke theft. These data have implications for understanding how intellectual property disputes are handled in other creative and scientific domains, as well as how character and action information are integrated into moral judgment more broadly.

    Am. Sociol. Rev. 83, 933 (2018).

  4. Health

    Gene for preeclampsia

    1. Paula A. Kiberstis

    Preeclampsia is a serious complication of pregnancy that often presents as an increase in maternal blood pressure. The disorder is more prevalent and severe in women with African ancestry, most likely because of genetic factors. Reidy et al. have been investigating a variant of the gene encoding apolipoprotein L1 (APOL1), which was previously shown to confer a high risk of kidney disease in black Americans. Studying two independent populations of pregnant black women, they found that preeclampsia was associated with the APOL1 high-risk genotype. Interestingly, it was the genotype of the fetus, not the mother, that mattered. The fetal APOL1 high-risk genotype may be linked to one in eight cases of preeclampsia in black women.

    Am. J. Hum. Genet. 103, 367 (2018).

  5. Neurodevelopment

    Sticky order for neurites

    1. Pamela J. Hines

    Nematode nerve cells are bundled in a specific order.

    IMAGE: HEITI PAVES/ALAMY STOCK PHOTO

    How do biological systems assemble in an ordered way, particularly in complex organs like the brain? One idea is that order emerges from multiple simple, local interactions. To explore this question, Yip and Heiman examined the organization of the sensory neurons of the nematode Caenorhabditis elegans. The amphid sense organ sends processes to the anterior of the worm to detect environmental conditions. The dendrites that make up these nerves are bundled in an ordered manner. Close to the nose, one dendrite occupies the middle of the bundle. A little further away from the nose, this dendrite cedes the middle track to another dendrite. The ordering is determined by cell-adhesion molecules expressed by the neurons themselves. The stereotypical organization of dendrite order might facilitate nonsynaptic signaling across dendrites.

    eLife 7, e35825 (2018).

  6. Thermal Transport

    Blowing by the blackbody limit

    1. Brent Grocholski

    The blackbody limit tells us the maximum amount of heat that can be emitted from an object. However, this limit is known to be no limit at all when the spacing between objects is small enough. Thompson et al. show that the blackbody limit can be circumvented when the emitting objects themselves are small. More importantly, they demonstrate a massive, hundredfold enhancement relative to the classical blackbody limit using nanoscale membranes. This opens the door to tailoring nanoscale materials for enhanced thermal absorption and emission applications.

    Nature 561, 216 (2018).

  7. Electron Imaging

    Imaging with ghostly electrons

    1. Ian S. Osborne

    Ghost imaging is a computational imaging approach that uses correlations between a signal beam that interacts with a sample and a reference beam that doesn't. The correlations are then used to reconstruct an image of the sample and can, in principle, be used to image samples with very weak signal beams that might otherwise be damaged with a typical probe beam. Already demonstrated for optics and atoms, Li et al. now extend the method of ghost imaging to electrons. To circumvent the difficulty of splitting an electron beam, they instead used a structured electron beam to probe the sample. They show that a reconstructed image of a sample with a lower electron dose than that used in direct imaging methods can be faithfully produced. This technique could reduce acquisition time and avoid damaging sensitive samples in electron imaging applications.

    Phys. Rev. Lett. 121, 114801 (2018).