Catálogo de publicaciones - revistas

<jats:title>Gut reasons to brush your teeth</jats:title> <jats:p> Some gut conditions, such as inflammatory bowel disease (IBD), ulcerative colitis, and Crohn's disease (CD), are associated with imbalances in the gut microbe community. The causes of these intractable diseases have been difficult to discern. Atarashi <jats:italic>et al.</jats:italic> took samples from the mouths of IBD and CD patients and inoculated the extracted bacteria into germ-free mice (see the Perspective by Cao). Some of the inoculated mice showed strong proliferation of T helper 1 cells associated with the establishment of oral <jats:italic>Klebsiella</jats:italic> species in the colon. <jats:italic>Klebsiella</jats:italic> can be resistant to multiple antibiotics and are able to replace normal colon microbes after antibiotic therapy. Now we know that they probably originate from the mouth and could potentially contribute to bowel disease. </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="6361" page="359" related-article-type="in-this-issue" vol="358" xlink:href="10.1126/science.aan4526">359</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6361" page="308" related-article-type="in-this-issue" vol="358" xlink:href="10.1126/science.aap9298">308</jats:related-article> </jats:p>

<jats:title>Recent natural selection in a wild bird</jats:title> <jats:p> Many studies have found evidence of rapid evolution in response to environmental change. In most cases, there has been some suggestion of which traits might be most responsive ahead of time. Bosse <jats:italic>et al.</jats:italic> turn this approach on its head by using genomic regions with a signature of selection to identify traits that are changing. In great tits ( <jats:italic>Parus major</jats:italic> ) in the United Kingdom, genomic regions showing selection invariably contained genes associated with bill growth. Indeed, U.K. birds not only have longer bills, but these longer bills are associated with increased fitness. These changes likely reflect an increase in domestic garden bird feeders over the past several decades. </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="6361" page="365" related-article-type="in-this-issue" vol="358" xlink:href="10.1126/science.aal3298">365</jats:related-article> </jats:p>

<jats:title>Memory transfer for long-term storage</jats:title> <jats:p> Explicit memory formation involves the transfer of rapidly encoded information from the hippocampus to long-term storage sites in the association cortex. Khodagholy <jats:italic>et al.</jats:italic> developed a microelectrode system for large-scale simultaneous electrophysiological monitoring of multiple sites in the rat neocortex. They observed discrete high-frequency neocortical oscillations called ripples only in the association cortex. These cortical ripples shared many properties with hippocampal ripples. Hippocampal ripples were coupled with cortical ripples in the posterior parietal cortex, an association cortical area linked to navigational planning. This coupling was increased during sleep after the induction of long-term hippocampal-dependent spatial memory. </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="6361" page="369" related-article-type="in-this-issue" vol="358" xlink:href="10.1126/science.aan6203">369</jats:related-article> </jats:p>

<jats:title>Refueling an enzyme</jats:title> <jats:p> Lipoic acid is an eight-carbon fatty acid in which sulfur groups are appended on two carbon atoms by the enzyme lipoyl synthase (LipA). LipA provides the sulfurs from an auxiliary [4Fe-4S] cluster. McCarthy and Booker show that in <jats:italic>Escherichia coli</jats:italic> , the auxiliary LipA cluster is reconstituted by the iron-sulfur cluster carrier protein NfuA (see the Perspective by Rosenzweig). This occurs fast enough that LipA can act catalytically in the final step of lipoic acid biosynthesis. </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="6361" page="373" related-article-type="in-this-issue" vol="358" xlink:href="10.1126/science.aan4574">373</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6361" page="307" related-article-type="in-this-issue" vol="358" xlink:href="10.1126/science.aap9299">307</jats:related-article> </jats:p>

<jats:title>Structure of human mTORC1 components</jats:title> <jats:p> The mTORC1 (mechanistic target of rapamycin complex 1) complex garners much attention as a signaling hub that coordinates input from growth-factor receptors and nutrient availability with metabolism and cell growth and proliferation. de Araujo <jats:italic>et al.</jats:italic> report the crystal structure of the LAMTOR (or “Ragulator”) complex that helps assemble mTORC1 at the lysosomal membrane for activation. The structure and functional studies reveal how LAMTOR1 wraps around the other subunits to hold them in place and interacts with the Rag guanosine triphosphatases in the 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="6361" page="377" related-article-type="in-this-issue" vol="358" xlink:href="10.1126/science.aao1583">377</jats:related-article> </jats:p>

<jats:title>A strategy for drug discovery</jats:title> <jats:p> Dopamine receptors are G protein-coupled receptors implicated in many neurological disorders. Different families of dopamine receptors are involved in different signaling pathways, so specificity is a key goal of therapeutics. Wang <jats:italic>et al.</jats:italic> present high-resolution crystal structures of the DRD4 dopamine receptor bound to the antipsychotic drug nemonapride. The high resolution of the structures facilitated ligand docking, and a DRD4-selective agonist was identified by computational screening of a large library, experimental testing of compounds with the best docking scores, and iterative cycles of docking and testing analogs of those compounds. The identified agonist had a high affinity for DRD4 and no measurable affinity for DRD2 or DRD3. </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="6361" page="381" related-article-type="in-this-issue" vol="358" xlink:href="10.1126/science.aan5468">381</jats:related-article> </jats:p>

<jats:title>Fans enable water strider adaptation</jats:title> <jats:p> Genomes of closely related organisms are similar but contain variations that enable different phenotypes and lifestyles. The origin of evolutionary innovations, such as insect wings and bird feathers, poses a challenge to evolutionary biology because the de novo emergence of complex traits cannot easily be explained by natural selection. Water-walking <jats:italic>Rhagovelia</jats:italic> insects evolved a propelling fan on the middle leg that is associated with life on fast-flowing streams. Santos <jats:italic>et al.</jats:italic> discovered that the <jats:italic>geisha</jats:italic> and <jats:italic>mother-of-geisha</jats:italic> genes underlie fan development and evolution and that this evolutionary innovation is essential to the adaptation of <jats:italic>Rhagovelia</jats:italic> to its environment. Thus, the evolution of taxon-restricted genes can contribute directly to taxon-restricted novelties that allow access to unexploited ecological niches. </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="6361" page="386" related-article-type="in-this-issue" vol="358" xlink:href="10.1126/science.aan2748">386</jats:related-article> </jats:p>

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