Catálogo de publicaciones - revistas

<jats:title>Rapid ryanodol route</jats:title> <jats:p> The plant-derived compound ryanodine and its hydrolyzed cousin ryanodol are biochemically interesting for their calcium-regulating capacity and chemically interesting for their dense tangle of carbon rings brimming with oxygen appendages. Chuang <jats:italic>et al.</jats:italic> report an efficient 15-step asymmetric synthesis of ryanodol from the structurally much simpler terpene pulegone (see the Perspective by Verdaguer). Key steps include a Pauson-Khand cyclization of a tethered alkene and alkyne with carbon monoxide to set the ring motifs, followed by an oxidation using selenium dioxide that delivers three different oxygen substituents in tandem. </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="6302" page="912" related-article-type="in-this-issue" vol="353" xlink:href="10.1126/science.aag1028">912</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6302" page="866" related-article-type="in-this-issue" vol="353" xlink:href="10.1126/science.aah5871">866</jats:related-article> </jats:p>

<jats:title>Shining a fast light on diamonds</jats:title> <jats:p> Conceptually, the electronic structure of matter is a fixed scaffold of energy levels, which electrons climb with the help of light absorption. In reality, the light's electromagnetic field distorts the scaffold, a phenomenon that becomes increasingly evident with rising field intensity. Lucchini <jats:italic>et al.</jats:italic> studied a manifestation of this phenomenon, termed the dynamical Franz Keldysh effect, in diamond substrates exposed to sudden, moderately intense infrared fields. Using attosecond probe pulses and accompanying theoretical simulations, they resolved and accounted for the extremely rapid ensuing electron dynamics. </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="6302" page="916" related-article-type="in-this-issue" vol="353" xlink:href="10.1126/science.aag1268">916</jats:related-article> </jats:p>

<jats:title>A seismic “weather bomb” detector</jats:title> <jats:p>Seismic tomography is like an x-ray of Earth's interior, except that it uses earthquakes for the illumination. Earthquakes are imperfect illuminators because they are clustered on plate boundaries, leaving much of the interior in the shadows. Using a seismic array in Japan, Nishida and Takagi detected seismic waves that they attribute to a severe and distant North Atlantic storm called a “weather bomb” (see the Perspective by Gerstoft and Bromirski). The seismic energy traveling from weather bombs through the Earth appears to be capable of illuminating the many dark patches of Earth's interior.</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="6302" page="919" related-article-type="in-this-issue" vol="353" xlink:href="10.1126/science.aaf7573">919</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6302" page="869" related-article-type="in-this-issue" vol="353" xlink:href="10.1126/science.aag1616">869</jats:related-article> </jats:p>

<jats:title>Harnessing complexity in ecology</jats:title> <jats:p>Ecology concerns the behavior of complex, dynamic, interconnected systems of populations, communities, and ecosystems over time. Yet ecological time series can be relatively short, owing to practical limits on study duration. Ye and Sugihara introduce an analytical approach called multiview embedding, which harnesses the complexity of short, noisy time series that are common in ecology and other disciplines such as economics. Using examples from published data sets, they show how this approach enhances the tractability of complex data from multiple interacting components and offers a way forward in ecological forecasting.</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="6302" page="922" related-article-type="in-this-issue" vol="353" xlink:href="10.1126/science.aag0863">922</jats:related-article> </jats:p>

<jats:title>Visualizing gene expression in nuclei</jats:title> <jats:p> Gene expression can vary greatly within a single cell. Using techniques that they developed for sequencing single nuclei and labeling proliferating cells in vivo, Habib <jats:italic>et al.</jats:italic> performed RNA sequencing of 1402 single nuclei from the adult mouse hippocampus. Combining this approach with a clustering algorithm for single-cell and -nucleus RNA sequencing data delineated specific cell types during cell differentiation and development. By providing polyadenylated RNA from nuclei alone, as opposed to cytoplasmic RNA, these methods open the application of single-cell transcriptomics to tissues in which individual cells are difficult to isolate. </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="6302" page="925" related-article-type="in-this-issue" vol="353" xlink:href="10.1126/science.aad7038">925</jats:related-article> </jats:p>

<jats:p>Activation of the serine-threonine kinase Akt promotes the survival and proliferation of various cancers. Hypoxia promotes the resistance of tumor cells to specific therapies. We therefore explored a possible link between hypoxia and Akt activity. We found that Akt was prolyl-hydroxylated by the oxygen-dependent hydroxylase EglN1. The von Hippel–Lindau protein (pVHL) bound directly to hydroxylated Akt and inhibited Akt activity. In cells lacking oxygen or functional pVHL, Akt was activated to promote cell survival and tumorigenesis. We also identified cancer-associated Akt mutations that impair Akt hydroxylation and subsequent recognition by pVHL, thus leading to Akt hyperactivation. Our results show that microenvironmental changes, such as hypoxia, can affect tumor behaviors by altering Akt activation, which has a critical role in tumor growth and therapeutic resistance.</jats:p>

<jats:title>New insights into norovirus entry</jats:title> <jats:p> There's no escaping norovirus when you have it—the symptoms from this gastroenteritis-causing virus, though brief, are often debilitating. Preventing infections will rely on improving our understanding of how norovirus enters host cells. Orchard <jats:italic>et al.</jats:italic> show that the entry of murine norovirus (MNoV) into host cells requires a protein called CD300lf. In cell culture, mouse cells needed to express CD300lf in order for MNoV binding, entry, and replication to occur. Deleting the gene encoding CD300lf in mice protected them against MNoV infection. Human cells expressing CD300lf allowed MNoV to break the species barrier, a finding that may lead to new insights into the infectivity of this virus. </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="6302" page="933" related-article-type="in-this-issue" vol="353" xlink:href="10.1126/science.aaf1220">933</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>