Editors' Choice

Science  25 Oct 2019:
Vol. 366, Issue 6464, pp. 441
  1. Behavior

    Dogs' brains and behaviors

    1. Pamela J. Hines

    Signs of human selection for behavioral specializations is evident in dogs' brains.

    PHOTO: PM IMAGES/GETTY IMAGES

    Dogs have been bred for traits ranging from herding and hunting to companionship. Attributes such as trainability or highly tuned olfaction characterize different breeds. Using magnetic resonance imaging, Hecht et al. scanned the brains of dogs from 10 breed groups defined by behavioral specializations. Although dogs showed diversity in craniofacial shape and brain volume, brain size was not strictly defined by body size. Brain networks were identified that related to behavioral specializations roughly corresponding to social bonding, taste and smell, physical movement, and affective and instinctual functions. The results show that the fingerprints of humans' selective interest in particular types of behaviors is evident in the evolution of dogs' brains.

    J. Neurosci. 39, 7748 (2019).

  2. Signaling

    Network rewiring in cancer

    1. L. Bryan Ray

    Cancer-causing mutations are likely to modulate existing signaling networks rather than generate newly rewired networks. During tumor growth, tyrosine phosphorylation offers a candidate mechanism for transient alteration of physiological function because of its pivotal role in cell signaling. Working with mouse lung tissue samples, Lundby et al. used advances in mass spectrometry and proteomics to examine how oncogenic mutations in the epidermal growth factor receptor lead to changes in signals transmitted through its phosphorylated tyrosine residues. The authors focused on one mutation that alters a site three residues away from a phosphorylated tyrosine. This mutation not only abolished recruitment of the normal complex of proteins that interact with the site but also triggered interaction with different proteins that promoted oncogenic signaling. These findings could reveal new targets for anticancer therapies.

    Cell 179, 543 (2019).

  3. X-Ray Imaging

    Adding dynamics to x-ray microscopy

    1. Ian S. Osborne

    The x-ray beam of the European X-Ray Free-Electron Laser facility (EuXFEL)

    PHOTO: EUROPEAN XFELN

    The development of third-generation x-ray sources, such as synchrotrons and free-electron lasers, over the past two decades has provided light-beam brilliance and coherence that can be used to reveal structural details with exquisite spatial resolution. More recent efforts have focused on developing a dynamic capability that would reveal detailed snapshots of ultrafast structural and electronic processes occurring within solid-state and biological samples. By modulating the x-ray beam at megahertz frequencies, Vagovič et al. introduce a technique implemented at the European X-ray Free-Electron Laser (EuXFEL) facility that provides microsecond temporal resolution along with micrometer spatial resolution and a better signal-to-noise ratio in the images. The results illustrate a promising route for the further development of temporally resolved x-ray imaging.

    Optica 6, 1106 (2019).

  4. Genomics

    The thermal adaptation of the proteome

    1. Laura M. Zahn

    Climate change is likely to cause new and extreme environmental conditions, and we have little understanding of how species will cope. Caddisfly larvae live wrapped in protective cases of grit or fibers among the stones of fast-flowing freshwater streams. Ebner et al. examined the proteome of the northern European caddisfly Crunoecia irrorata when raised at different temperatures between 10° and 20°C. This species normally lives in the steady environment of groundwater springs, but this study shows that it appears to have compensatory mechanisms that respond to warming. The authors found that differential expression of proteins with functional annotation in candidate thermoregulatory systems increased as temperature increased. It seems that C. irrorata has a higher tolerance to temperature variation than previously thought.

    Molec. Ecol. 10.1111/mec.15225 (2019).

  5. Microbiology

    Broadening microbiota transplants

    1. Gemma Alderton

    Fecal microbiota transplantation (FMT) has been successful at treating Clostridium difficile infections, although recent events show there are major risks of antibiotic resistant pathogen transfer (as noted by a recent U.S. Food and Drug Administration alert). FMT is also being investigated to treat bowel cancers and improve therapeutic responses. The gut is not the only site in which the symbiotic microbiota can promote homeostasis. In particular, the vagina contains a specialized microbiota that can be altered after bacterial infection. Lev-Sagie et al. treated five patients with intractable and recurrent bacterial vaginosis with vaginal microbiota transplantation (VMT) from healthy donors. Four of the women underwent long-term remission and reconstitution of a normal microbiota. No adverse effects were seen in this study, indicating that VMT could be tested in randomized clinical trials.

    Nat. Med. 25, 1500 (2019).

  6. Sediment Transport

    Worldwide river sediment flux

    1. Brent Grocholski

    The sediment flux coming out of rivers into the ocean is important for river systems and resource management. Li et al. compiled a dataset of sediment fluxes for more than 4000 rivers worldwide. The data provide a picture of sediment and water flux that future research data can be compared against. The authors found that many rivers have lower sea-going sediment flux partly as a result of upstream dams and irrigation practices. Changes in water and sediment fluxes because of human impact and climate alters coastal environment and biogeochemical cycles.

    Sci. Bull. 10.1016/j.scib.2019.09.012 (2019).

  7. Metabolomics

    Parallel profiling of an enzyme family

    1. Michael A. Funk

    Uncharacterized gene sequences are annotated based on the function of distant relatives and often have very different functions in reality. Kim et al. developed a method based on untargeted metabolomics to fill in the gaps and assign precise function to members of the M20 peptidase family, which generally catalyze amide bond cleavage. Viral transduction of each enzyme in mice and comparative analysis of levels of metabolites in liver tissue recovered known enzyme functions for two family members and assigned a new function, dipeptide cleavage, for one of the orphan enzymes in this family.

    Cell Chem. Biol. 10.1016/j.chembiol.2019.09.009 (2019).

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