Catálogo de publicaciones - revistas

<jats:title>Born to be a wildling</jats:title> <jats:p> Inbred laboratory mouse strains are used extensively in basic and translational immunology research. However, the commensal and pathogenic repertoire of resident microbes encountered in the wild is not replicated in a lab setting. This can substantially distort how the immune system develops and functions, leading to false assumptions of how our own “wild” immune system works. Rosshart <jats:italic>et al.</jats:italic> circumvented this dilemma by implanting lab-strain embryos into wild mice (see the Perspective by Nobs and Elinav). The resultant “wildlings” had a systemic immune phenotype and a bacterial, viral, and fungal microbiome much closer to those of their wild counterparts. In two preclinical experiments, where lab mice had previously failed to predict the human response to drug treatments, wildlings accurately phenocopied patient outcomes. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" related-article-type="in-this-issue" xlink:href="10.1126/science.aaw4361">eaaw4361</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6452" page="444" related-article-type="in-this-issue" vol="365" xlink:href="10.1126/science.aay2864">444</jats:related-article> </jats:p>

<jats:title>It's a dog's life</jats:title> <jats:p> Canine transmissible venereal tumor is one of the few cancer lineages that is transferred among individuals through contact. It arose millennia ago and has been evolving independently from its hosts ever since. Baez-Ortega <jats:italic>et al.</jats:italic> looked at the phylogenetic history of the cancer and describe several distinctive mutational patterns (see the Perspective by Maley and Shibata). Most notably, both positive and negative selection show only weak or distant signals. This suggests that the main driver of the lineage's evolution is neutral genetic drift. Understanding the influence of drift may reshape how we think about long-term cancer evolution. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" related-article-type="in-this-issue" xlink:href="10.1126/science.aau9923">eaau9923</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6452" page="440" related-article-type="in-this-issue" vol="365" xlink:href="10.1126/science.aay2859">440</jats:related-article> </jats:p>

<jats:title>Protein unfolding, one substrate at a time</jats:title> <jats:p> Ubiquitin marks proteins for degradation by the proteasome. However, many substrates cannot be directly degraded because they are well folded or are located in cell membranes or in multimeric complexes. These proteins are first unfolded by the Cdc48 adenosine triphosphatase (ATPase), which forms a hexameric assembly that pulls polypeptides through its central pore. Twomey <jats:italic>et al.</jats:italic> determined structures of Cdc48 at an initiation stage of substrate processing. Surprisingly, a ubiquitin molecule in the substrate-linked polyubiquitin chain could be unfolded simply by binding to the Cdc48 complex. A segment of the unfolded ubiquitin inserts into the ATPase ring and initiates substrate unfolding. This explains why Cdc48 can deal with a broad range of substrates—even ones that are folded. Cooney <jats:italic>et al.</jats:italic> report the cryo–electron microscopy structure of Cdc48 in complex with an authentic substrate. In contrast to previously reported Cdc48 structures, an asymmetric spiraling assembly wraps around the extended substrate polypeptide. Thus, Cdc48 uses a hand-over-hand mechanism of translocation, which supports a common mechanism for protein substrate unfolding for AAA+ ATPases. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" related-article-type="in-this-issue" xlink:href="10.1126/science.aax1033">eaax1033</jats:related-article> , p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6452" page="502" related-article-type="in-this-issue" vol="365" xlink:href="10.1126/science.aax0486">502</jats:related-article> </jats:p>

<jats:title>A light-harvesting array in diatoms</jats:title> <jats:p> Photosynthetic organisms use huge arrays of pigments to draw light energy into the core of photosystem II. The arrangement of these pigments influences how much energy reaches the reaction center. Pi <jats:italic>et al.</jats:italic> determined the structure of photosystem II from a diatom in complex with an antenna of fucoxanthin–chlorophyll a/c binding proteins (FCPs) (see the Perspective by Büchel). The specialized pigments in this complex allow microalgae to harvest light within a wide range of the visible spectrum. The FCPs are arranged in a pattern analogous to light-harvesting complexes in plants. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" related-article-type="in-this-issue" xlink:href="10.1126/science.aax1033">eaax4406</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6452" page="447" related-article-type="in-this-issue" vol="365" xlink:href="10.1126/science.aay3036">447</jats:related-article> </jats:p>

<jats:p> Forty years ago this summer, a small group of atmospheric and ocean scientists met in Woods Hole, Massachusetts, to project the future impacts on Earth's climate from atmospheric release of carbon dioxide (CO <jats:sub>2</jats:sub> ) from fossil fuel combustion. Frank Press, head of the United States Office of Science and Technology Policy and Science Adviser to President Carter, requested that the National Academy of Sciences conduct the study for the benefit of policymakers. On the basis of then-current trends, the 1979 committee, led by Jule Charney of the Massachusetts Institute of Technology, assumed that atmospheric CO <jats:sub>2</jats:sub> concentrations would reach double the preindustrial values sometime in the first half of the 21st century. They calculated that as a result, the average global surface temperature would increase by 3° ± 1.5°C, with the greatest warming at high latitudes—the first assessment of its kind. The Charney committee also noted in the models a lag on the order of decades between CO <jats:sub>2</jats:sub> release and the resulting temperature rise. This delay, from disequilibrium effects with the ocean, masks pending temperature increases long before they are apparent. </jats:p>

<jats:p>A roundup of weekly science policy and related news.</jats:p>

<jats:p>Biomedical studies on Zika virus, AIDS, and more imperiled.</jats:p>