Catálogo de publicaciones - revistas

<jats:title>Shedding light on disordered proteins</jats:title> <jats:p>Disordered proteins often fold as they bind to a partner protein. There could be many different molecular trajectories between the unbound proteins and the bound complex. Most methods to measure transition paths rely on monitoring a single distance, making it difficult to resolve complex pathways. Kim and Chung used fast three-color single-molecule Foster resonance energy transfer (FRET) to simultaneously probe distance changes between the two ends of an unfolded protein and between each end and a probe on the partner protein. They show that binding can be initiated by diverse conformations and that the molecules are held together by non-native interactions as the disordered protein folds. This allows the association to be diffusion limited because most collisions lead to binding.</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="6496" page="1253" related-article-type="in-this-issue" vol="368" xlink:href="10.1126/science.aba3854">1253</jats:related-article> </jats:p>

<jats:title>Here, there, and everywhere</jats:title> <jats:p> No place is safe from plastic pollution. Brahney <jats:italic>et al.</jats:italic> show that even the most isolated areas in the United States—national parks and national wilderness areas—accumulate microplastic particles after they are transported there by wind and rain (see the Perspective by Rochman and Hoellein). They estimate that more than 1000 metric tons per year fall within south and central western U.S. protected areas. Most of these plastic particles are synthetic microfibers used for making clothing. These findings should underline the importance of reducing pollution from such materials. </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="6496" page="1257" related-article-type="in-this-issue" vol="368" xlink:href="10.1126/science.aaz5819">1257</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6496" page="1184" related-article-type="in-this-issue" vol="368" xlink:href="10.1126/science.abc4428">1184</jats:related-article> </jats:p>

<jats:title>How cells monitor mitogen availability</jats:title> <jats:p> Classical experiments indicated that cells sense the mitogens or growth factors that control cell division within a limited window during the cell cycle. Min <jats:italic>et al.</jats:italic> reexamined this issue with high-throughput live-cell imaging and temporally controlled perturbations to more closely monitor dynamic signal processing. Human epithelial cells in culture integrated the mitogenic signals sensed throughout the cell cycle. One important factor was the control of translation rates, which influenced the amount of cyclin D, thus regulating proliferation. The results may also help to explain how cells maintain a uniform size. </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="6496" page="1261" related-article-type="in-this-issue" vol="368" xlink:href="10.1126/science.aay8241">1261</jats:related-article> </jats:p>

<jats:title>Very fast CRISPR on demand</jats:title> <jats:p> Numerous efforts have been made to improve the temporal resolution of CRISPR-Cas9–mediated DNA cleavage to the hour time scale. Liu <jats:italic>et al.</jats:italic> developed a Cas9 system that achieved genome-editing manipulation at the second time scale (see the Perspective by Medhi and Jasin). Part of the guide RNA is chemically caged, allowing the Cas9-guide RNA complex to bind at a specific genomic locus without cleavage until activation by light. This fast CRISPR system achieves genome editing at high temporal resolution, enabling the study of early molecular events of DNA repair processes. This system also has high spatial resolution at short time scales, allowing editing of one genomic allele while leaving the other unperturbed. </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="6496" page="1265" related-article-type="in-this-issue" vol="368" xlink:href="10.1126/science.aay8204">1265</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6496" page="1180" related-article-type="in-this-issue" vol="368" xlink:href="10.1126/science.abc3997">1180</jats:related-article> </jats:p>

<jats:title>Canaries changing colors</jats:title> <jats:p> Many animals are sexually dimorphic, with different phenotypes in males and females. To identify the genetic basis of sexual differences in bird coloration, Gazda <jats:italic>et al.</jats:italic> investigated red coloration in mosaic canaries and related species (see the Perspective by Chen). Using a combination of genetic crosses, genomic mapping, transcriptomics, and comparative analyses, the authors show that trans-regulation of the carotenoid-processing gene <jats:italic>BCO2</jats:italic> is involved in sexual dichromatism. Although such variation in coloration among the sexes is common, particularly in birds, there are few candidate genes known to be involved. This study helps to elucidate the molecular mechanisms that underlie the evolution of dichromatism and may aid in uncovering sexually selected traits. </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="6496" page="1270" related-article-type="in-this-issue" vol="368" xlink:href="10.1126/science.aba0803">1270</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6496" page="1185" related-article-type="in-this-issue" vol="368" xlink:href="10.1126/science.abc2242">1185</jats:related-article> </jats:p>

<jats:title>An antibody defense against COVID-19</jats:title> <jats:p> One of the responses of the immune system to invading viruses is the production of antibodies. Some of these are neutralizing, meaning that they prevent the virus from being infectious, and can thus be used to treat viral diseases. Wu <jats:italic>et al.</jats:italic> isolated four neutralizing antibodies from a convalescent coronavirus disease 2019 (COVID-19) patient. Two of the antibodies, B38 and H4, blocked the receptor binding domain (RBD) of the viral spike protein from binding to the cellular receptor, angiotensin-converting enzyme 2 (ACE2). The structure of the RBD bound to B38 shows that the B38-binding site overlaps with the binding site for ACE2. Although H4 also blocks RBD binding to ACE2, it binds at a different site, and thus the two antibodies can bind simultaneously. This pair of antibodies could potentially be used together in clinical applications. </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="6496" page="1274" related-article-type="in-this-issue" vol="368" xlink:href="10.1126/science.abc2241">1274</jats:related-article> </jats:p>