Catálogo de publicaciones - revistas

<jats:title>Predicting extinction in a changing world</jats:title> <jats:p>There is great interest in understanding how species might respond to our changing climate, but predictions have varied greatly. Urban looked at over 130 studies to identify the level of risk that climate change poses to species and the specific traits and characteristics that contribute to risk (see the Perspective by Hille Ris Lambers). If climate changes proceed as expected, one in six species could face extinction. Several regions, including South America, Australia, and New Zealand, face the greatest risk. Understanding these patterns will help us to prepare for, and hopefully prevent, climate-related loss of biodiversity.</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" issue="6234" page="571" related-article-type="in-this-issue" vol="348" xlink:href="10.1126/science.aaa4984">571</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6234" page="501" related-article-type="in-this-issue" vol="348" xlink:href="10.1126/science.aab2057">501</jats:related-article> </jats:p>

<jats:title>Pop goes the coccus</jats:title> <jats:p> Daughter cell separation in <jats:italic>Staphylococcus aureus</jats:italic> proceeds much like the cracking of an egg. So say Zhou <jats:italic>et al.</jats:italic> , who examined dividing cells with millisecond precision using high-speed videomicroscopy. Rather than proceeding gradually, tiny imperfections in the mother cell wall were seen to crack open, leaving two daughter cells linked by a hinge. </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" issue="6234" page="574" related-article-type="in-this-issue" vol="348" xlink:href="10.1126/science.aaa1511">574</jats:related-article> </jats:p>

<jats:title>A hierarchy of protein motions</jats:title> <jats:p> Functioning proteins are not static but explore complex conformational energy landscapes. Lewandowski <jats:italic>et al.</jats:italic> used multinuclear solid-state nuclear magnetic resonance experiments to measure protein motion over a broad range of temperatures and time scales. Above 160 K there was a strong coupling between solvent and protein motion. The hierarchy of motions as the temperature increased revealed the dynamic modes that relate solvent, sidechain, and backbone motion. </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" issue="6234" page="578" related-article-type="in-this-issue" vol="348" xlink:href="10.1126/science.aaa6111">578</jats:related-article> </jats:p>

<jats:title>Changing shape to destroy RNA</jats:title> <jats:p> Clustered regularly interspaced short palindromic repeats (CRISPRs) together with CRISPR-associated (Cas) proteins form an adaptive immune system that helps bacteria and archaea defend themselves against invading viruses and plasmids. CRISPR RNAs (crRNAs) target CRISPR-Cas protein complexes to the invaders, bringing about their destruction. Taylor <jats:italic>et al.</jats:italic> used cryo–electron microscopy to determine the structure of a 12-subunit CRISPR-Cas protein complex with crRNA from <jats:italic>Thermus thermophilus</jats:italic> , in the presence and absence of single-stranded target RNA. Binding to the target RNA causes a change in shape of the CRISPR-Cas complex that results in target recognition and destruction. </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" issue="6234" page="581" related-article-type="in-this-issue" vol="348" xlink:href="10.1126/science.aaa4535">581</jats:related-article> </jats:p>

<jats:title>Keeping jumping genes out of harm's way</jats:title> <jats:p> The genomes of most eukaryotes, including our own, are jam-packed with parasitic mobile DNA elements. Most are nonfunctional remnants, but a few are still active, capable of jumping about in our DNA, potentially causing serious damage to our genes. Nevertheless, they avoid landing in and disrupting coding regions. For example, in yeast, the retrotransposon Ty1 is targeted away from protein genes to positions upstream of yeast RNA polymerase III genes. Bridier-Nahmias <jats:italic>et al.</jats:italic> show that Ty1 is targeted to these “safe havens” through an interaction between a Ty1-encoded protein that controls its genome jumping activity and a subunit of the yeast RNA polymerase III complex. </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" issue="6234" page="585" related-article-type="in-this-issue" vol="348" xlink:href="10.1126/science.1259114">585</jats:related-article> </jats:p>

<jats:title>Early T cells keep autoimmunity at bay</jats:title> <jats:p> A major challenge faced by the immune system is to react to foreign substances, such as microbes, while simultaneously tolerating the self. Upsetting this balance leads to autoimmunity. Regulatory T cells (T <jats:sub>regs</jats:sub> ), are a subset of immune cells that help to maintain this balance. Yang <jats:italic>et al.</jats:italic> found that murine T <jats:sub>reg</jats:sub> cells generated very early in life are distinct from those generated in older animals and play an especially important role in keeping autoimmunity in check (see the Perspective by Tanaka and Sakaguchi). These changes are due to differences in the way T <jats:sub>regs</jats:sub> develop in the thymus in newborn versus adult mice. </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" issue="6234" page="589" related-article-type="in-this-issue" vol="348" xlink:href="10.1126/science.aaa7017">589</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6234" page="506" related-article-type="in-this-issue" vol="348" xlink:href="10.1126/science.aab2998">506</jats:related-article> </jats:p>

<jats:p>On this week's show: Sustainable seafood from developing countries, and a roundup of daily news stories.</jats:p>

<jats:p>A weekly roundup of information on newly offered instrumentation, apparatus, and laboratory materials of potential interest to researchers.</jats:p>