Catálogo de publicaciones - revistas

<jats:title>A trio helps activate C-H bonds in alcohols</jats:title> <jats:p> Enzymes can accelerate chemical reactions by activating specific portions of a molecule through well-placed H bonds. Jeffrey <jats:italic>et al.</jats:italic> showcase the power of H-bonding in a synthetic context. Here, reactivity at the C centers of alcohols is selectively induced by using an H-bonding catalyst to bind the hydroxyl group of the alcohol. The adjacent C-H bonds now become susceptible to a reaction accelerated by another pair of catalysts. In combination, the trio of catalysts promotes C-C bond formation at the alcohol C within an array of competing sites. </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="6255" page="1532" related-article-type="in-this-issue" vol="349" xlink:href="10.1126/science.aac8555">1532</jats:related-article> </jats:p>

<jats:title>Flushing the deep ocean</jats:title> <jats:p> Have changes in ocean circulation contributed to the sudden increases in the concentration of atmospheric carbon dioxide that occurred during the last deglaciation? Chen <jats:italic>et al.</jats:italic> provide a high-resolution radiocarbon record for that time, derived from deep sea corals. This record shows that two deep ocean “flushing” events were accompanied by abrupt rises in carbon dioxide and Northern Hemispheric warming. There is a clear connection between these ocean processes and the atmosphere during this interval. </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="6255" page="1537" related-article-type="in-this-issue" vol="349" xlink:href="10.1126/science.aac6159">1537</jats:related-article> </jats:p>

<jats:title>Climate change decoupling mutualism</jats:title> <jats:p> Many coevolved species have precisely matched traits. For example, long-tongued bumblebees are well adapted for obtaining nectar from flowers with long petal tubes. Working at high altitude in Colorado, Miller-Struttmann <jats:italic>et al.</jats:italic> found that long-tongued bumblebees have decreased in number significantly over the past 40 years. Short-tongued species, which are able to feed on many types of flowers, are replacing them. This shift seems to be a direct result of warming summers reducing flower availability, making generalist bumblebees more successful than specialists and resulting in the disruption of long-held mutualisms. </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="6255" page="1541" related-article-type="in-this-issue" vol="349" xlink:href="10.1126/science.aab0868">1541</jats:related-article> </jats:p>

<jats:title>Dissecting the mitochondrial entry portal</jats:title> <jats:p> Mitochondria, the powerhouses of the cell, are mainly composed of proteins made in the cytosol. These newly synthesized proteins need to be imported across the organelle's membrane through dedicated protein import machinery. Shiota <jats:italic>et al.</jats:italic> have worked out the architecture and mechanism of the mitochondrial protein import channel. </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="6255" page="1544" related-article-type="in-this-issue" vol="349" xlink:href="10.1126/science.aac6428">1544</jats:related-article> </jats:p>

<jats:title>Parasitic DNA targets a genomic home</jats:title> <jats:p> Long-terminal-repeat (LTR) retrotransposons are a form of parasitic DNA that can jump around within the host's genome. To avoid damaging resident genes, they have been selected to integrate away from protein-coding sequences. For instance, the fission yeast LTR retrotransposon Tf1 inserts at nucleosome-free regions in gene promoters. Jacobs <jats:italic>et al.</jats:italic> show that Tf1 is directed to these insertion sites by a specific DNA binding protein, Sap1, which forms DNA replication–fork barriers. </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="6255" page="1549" related-article-type="in-this-issue" vol="349" xlink:href="10.1126/science.aaa3810">1549</jats:related-article> </jats:p>

<jats:p> This issue of <jats:italic>Science</jats:italic> includes the program of the 2016 AAAS Annual Meeting. </jats:p> <jats:p>2016 “Session I” Meetings will be held between January 9 and March 25 in Ventura, CA and Galveston, TX in the United States, and internationally in the Tuscany region of Italy.</jats:p> <jats:p> A <jats:ext-link xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="uri" xlink:href="http://www.sciencemag.org/cgi/reprint/349/6255/1554.pdf">PDF</jats:ext-link> of the program as it appears in this issue is available here; for more information on the meeting (including registration forms and information on accommodations), please visit <jats:ext-link xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="uri" xlink:href="www.grc.org">www.grc.org</jats:ext-link> . </jats:p>

<jats:p>Engineered systems of genes and other molecular components created through synthetic biology make medical treatments more effective and promise cures for a range of health problems. Perhaps equally important, recent technologies make it easier for a broader range of scientists to apply synthetic-biology approaches that drive expanding clinical applications, from designing new diagnostics and building molecularly engineered tissues to developing new drugs and vaccines.</jats:p>

<jats:p>For a better and deeper understanding of the biological processes involved in diseases, as well as finding relevant therapeutic approaches, more and more complex methods and applications are being developed and used every day. Drug discovery and translational research is not only found in biopharma R&amp;D laboratories, but also becoming an increasingly larger part of the academic environment. The need for automation in such labs is therefore growing dramatically. However, automation has many advantages beyond simply higher throughput. Robots and other automation tools enable the development of robust and reliable workflows that meet the requirements of new and complex translational research methods. Manual approaches often do not deliver the reproducibility and the accuracy needed for acceptable data quality. In such cases, small-scale automation devices—such as state-of-the-art multimode microplate readers and microplate washers, highly sensitive microarray scanners, and high throughput hybridization stations—can play a critical role in providing the necessary reliability and publication quality data. Using examples from neuroscience and cancer research, this webinar will discuss how small-scale automation in typical academic labs can be used to collect data that cannot be produced by standard manual approaches.</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:p>On this week's show: 3-parent gene therapy to treat mitochondrial diseases and a roundup of daily news stories.</jats:p>