Catálogo de publicaciones - revistas

<jats:title>How to optimize global food production</jats:title> <jats:p> Keeping societies stable and managing Earth's resources sustainably depend on doing a good, steady job producing and distributing food. West <jats:italic>et al.</jats:italic> asked what combinations of crops and regions offer the best chance of progress. Their analysis focused on reducing greenhouse gas emissions, nutrient pollution, water use, and food waste. They identify regions that are likely to yield the best balance between applying fertilizer to increase crop yields versus the resulting environmental impact. </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="6194" page="325" related-article-type="in-this-issue" vol="345" xlink:href="10.1126/science.1246067">325</jats:related-article> </jats:p>

<jats:title>Evolving from an enzyme and into a regulator</jats:title> <jats:p> Proteins, the work-horses of the cell, are made on a messenger RNA (mRNA) template. An enzyme called aminoacyl tRNA synthetases (AARSs) attaches the correct amino acid to a transfer RNA so that mRNA is accurately translated. Over evolution, additional sequences have been added to AARSs. Lo <jats:italic>et al.</jats:italic> found a large number of AARS variants in which the domain responsible for enzyme function was deleted. Ninety-four such variants had diverse signaling activities. Thus, AARSs are used both as enzymes and alternately as regulators of signaling pathways. </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="6194" page="328" related-article-type="in-this-issue" vol="345" xlink:href="10.1126/science.1252943">328</jats:related-article> </jats:p>

<jats:title>Taking a check on chromosome spacing</jats:title> <jats:p> Animal cells divide by mitosis. Chromosomes become condensed and congregate on the mitotic spindle in the center of the cell—the midzone. The spindle then separates sister chromosomes, pulling them to opposite ends of the cell, ready to form new daughter nuclei. Afonso <jats:italic>et al.</jats:italic> now show that chromosome separation is monitored by the level of midzone-associated Aurora B kinase activity (see the Perspective by Hadders and Lens). This process ensures that daughter nuclei only reassemble after sister chromosomes have successfully separated. </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="6194" page="332" related-article-type="in-this-issue" vol="345" xlink:href="10.1126/science.1251121">332</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6194" page="265" related-article-type="in-this-issue" vol="345" xlink:href="10.1126/science.1257267">265</jats:related-article> </jats:p>

<jats:title>How dynein makes the right moves</jats:title> <jats:p> The molecular motor cytoplasmic dynein moves a wide range of different intracellular cargoes. Dynein's activity in vivo requires another protein, dynactin, but exactly why that should be has been very unclear. Although in vitro experiments have provided some evidence that dynactin increases dynein's processivity, the resulting dynein motility has never come close to matching dynein's cargo-transporting activity in living cells. Now, McKenney <jats:italic>et al.</jats:italic> show that tripartite complexes of dynein, dynactin, and an adaptor molecule are highly processive in vitro, moving the sort of distances that dynein transports cargo in vivo (see the Perspective by Allan). </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="6194" page="337" related-article-type="in-this-issue" vol="345" xlink:href="10.1126/science.1254198">337</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6194" page="271" related-article-type="in-this-issue" vol="345" xlink:href="10.1126/science.1257245">271</jats:related-article> </jats:p>

<jats:p>On this week's show: A new tech to alter genes in the wild and a roundup of stories from our daily news site.</jats:p>

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

<jats:title>A structural approach to species interactions</jats:title> <jats:p> What determines the stability of ecological networks? Rohr <jats:italic>et al.</jats:italic> devised a conceptual approach to study interactions between species that emphasizes the role of network structure (see the Perspective by Pawar). Using the example of mutualistic networks of communities of plants and their pollinator species, they show how the structure of networks can determine the persistence of the interactions. Network structures and architectures observed in nature intrinsically match the most stable solution. This approach has promise for application to questions of ecological community stability under global change. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue <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.1253497">10.1126/science.1253497</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6195" page="383" related-article-type="in-this-issue" vol="345" xlink:href="10.1126/science.1256466">383</jats:related-article> </jats:p>

<jats:p> 2014 marks the centennial of the commencement of World War I. One connection between today and that seemingly long-ago war is how we make choices when the future seems obvious only in retrospect, in what former U.S. Secretary of State George P. Shultz refers to as a world “awash in change.” Max Hastings, in <jats:italic>Catastrophe 1914: Europe Goes to War</jats:italic> , summarizes his views on how the rulers of Europe allowed World War I to start, then continue with a loss of over 8.6 million soldiers: “It is more appropriate to call them deniers, who preferred to persist with supremely dangerous policies and strategies….” </jats:p>