Catálogo de publicaciones - revistas

<jats:title>Sites of vulnerability in SARS-CoV-2</jats:title> <jats:p> Antibodies that neutralize severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) could be an important tool in treating coronavirus disease 2019 (COVID-19). Brouwer <jats:italic>et al.</jats:italic> isolated 403 monoclonal antibodies from three convalescent COVID-19 patients. They show that the patients had strong immune responses against the viral spike protein, a complex that binds to receptors on the host cell. A subset of antibodies was able to neutralize the virus. Competition and electron microscopy studies showed that these antibodies target diverse epitopes on the spike, with the two most potent targeting the domain that binds the host receptor. </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="6504" page="643" related-article-type="in-this-issue" vol="369" xlink:href="10.1126/science.abc5902">643</jats:related-article> </jats:p>

<jats:title>Hitting SARS-CoV-2 in a new spot</jats:title> <jats:p> A key target for therapeutic antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the spike protein, a trimeric protein complex with each monomer comprising an S1 and an S2 domain that mediate binding to host cells and membrane fusion, respectively. In addition to the receptor binding domain (RBD), S1 has an N-terminal domain (NTD). In searching for neutralizing antibodies, there has been a focus on the RBD. Chi <jats:italic>et al.</jats:italic> isolated antibodies from 10 convalescent patients and identified an antibody that potently neutralizes the virus but does not bind the RBD. Cryo–electron microscopy revealed the epitope as the NTD. This NTD-targeting antibody may be useful to combine with RBD-targeting antibodies in therapeutic cocktails. </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="6504" page="650" related-article-type="in-this-issue" vol="369" xlink:href="10.1126/science.abc6952">650</jats:related-article> </jats:p>

<jats:title>Adapted to the task at hand</jats:title> <jats:p> RNA-based catalysts perform fundamental tasks in cellular RNA metabolism, especially in eukaryotes, where RNAs are cut by specialized ribonucleoproteins (RNPs) as part of ribosome assembly or messenger RNA regulation or splicing. Both RNA and protein components play a role in shaping how these large catalytic complexes interact with their RNA substrates. Lan <jats:italic>et al.</jats:italic> determined the cryo–electron microscopy structures of a yeast RNP called ribonuclease MRP both alone and bound to a small RNA substrate. Comparison with the related ribonuclease P revealed differences in both protein and RNA components that enable ribonuclease MRP to recognize substrates with a specific sequence motif, rather than purely recognizing RNA structure as ribonuclease P does. These structures aid in considering how RNPs evolved and why they remain central to eukaryotic RNA processing. </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="6504" page="656" related-article-type="in-this-issue" vol="369" xlink:href="10.1126/science.abc0149">656</jats:related-article> </jats:p>

<jats:title>Switching perception of friend and foe</jats:title> <jats:p> Lysine motif receptors in plants perceive glycans that signal the presence of pathogenic or symbiotic nitrogen-fixing microbes. Bozsoki <jats:italic>et al.</jats:italic> now define the portions of these receptors that create the discriminatory binding pocket (see the Perspective by Bisseling and Geurts). The motifs were conserved in receptors that initiate immune responses, reflecting the invariable nature of the chitin fragments that they sense. Conversely, the motifs in receptors that respond to symbiotic signals were more varied, reflecting the greater diversity of the lipochitooligosaccharides (Nod factors) that they sense. With domain swapping, the authors switched the Nod factor specificity of receptors from two legume species and also enabled a chitin receptor that was otherwise dedicated to the detection of pathogenic microbes to instead recognize Nod factors. </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="6504" page="663" related-article-type="in-this-issue" vol="369" xlink:href="10.1126/science.abb3377">663</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6504" page="620" related-article-type="in-this-issue" vol="369" xlink:href="10.1126/science.abd3857">620</jats:related-article> </jats:p>

<jats:title>Stabilizing monolayer nitrides with silicon</jats:title> <jats:p> Transition metal carbides and nitrides are nonlayered materials that in monolayer form have potentially useful electronic and chemical properties. These monolayers are usually made by chemical etching that produces flakes with surface defects that have poor air and water stability. Hong <jats:italic>et al.</jats:italic> report that introducing silicon during chemical vapor deposition growth of molybdenum nitride passivates the surface and prevents island formation. Centimeter-scale monolayer films of the semiconductor MoSi <jats:sub>2</jats:sub> N <jats:sub>4</jats:sub> form as a MoN <jats:sub>2</jats:sub> layer sandwiched by two Si-N bilayers. These layers possess high mechanical strength and ambient stability. </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="6504" page="670" related-article-type="in-this-issue" vol="369" xlink:href="10.1126/science.abb7023">670</jats:related-article> </jats:p>

<jats:title>Mapping metal sequences in MOFs</jats:title> <jats:p> Most metal-organic frameworks (MOFs) contain just one type of metal in the nodes connecting the organic linkers. Multivariate MOFs containing multiple metals can offer greater selectivity in sorption and catalytic properties, but determining the arrangement of metals in these materials is challenging. Ji <jats:italic>et al.</jats:italic> found that atom-probe tomography can reveal sequences of metals for MOF-74 single crystals containing combinations of cobalt, cadmium, lead, and manganese ions. In this MOF, the metals form oxide rods that are connected by the organic linker into a honeycomb lattice. The obtained sequences, which were tuned by varying the proportion of metals and synthesis temperature, could be random, short and long duplicates, and single metal insertions. </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="6504" page="674" related-article-type="in-this-issue" vol="369" xlink:href="10.1126/science.aaz4304">674</jats:related-article> </jats:p>

<jats:title>A helix of dipoles</jats:title> <jats:p> In magnetic materials, magnetic dipoles typically line up parallel or antiparallel to each other. However, more complex orderings, such as helical, can also occur. Khalyavin <jats:italic>et al.</jats:italic> found that in the material BiCu <jats:sub>0.1</jats:sub> Mn <jats:sub>6.9</jats:sub> O <jats:sub>12</jats:sub> , a helical order can be formed out of electric rather than magnetic dipoles. The material also harbors an associated structural helical order, which symmetry analysis suggests might be switchable with an applied electric field. </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="6504" page="680" related-article-type="in-this-issue" vol="369" xlink:href="10.1126/science.aay7356">680</jats:related-article> </jats:p>