Catálogo de publicaciones - revistas

<jats:title>Signaling ability and grit to academia</jats:title> <jats:p>In many professions, getting ahead requires evidence of both effort and ability. This is especially true if one is not a member of the dominant group and thus surmounting social norms. Breda and Hillion show that oral examiners of candidates for teaching positions in the French education system reward such applicants. Specifically, women applying for high-level teaching positions in male-dominated fields, such as physics and philosophy, are favored, as are men who apply in female-dominated fields, such as literature and foreign languages.</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="6298" page="474" related-article-type="in-this-issue" vol="353" xlink:href="10.1126/science.aaf4372">474</jats:related-article> </jats:p>

<jats:title>Resistance is not, after all, futile</jats:title> <jats:p> The parasitic plant known as dodder attaches to its hosts and sucks the life out of them. Oddly, the common tomato stands tall when under attack. Hegenauer <jats:italic>et al.</jats:italic> have leveraged that difference to identify part of the molecular defense system that protects tomato plants (see the Perspective by Ntoukakis and Gimenez-Ibanez). In a process analogous to defenses mounted against microbial infection, the host plant perceives a small-peptide signal from the parasitic plant and initiates defense responses. The candidate receptor isolated from the tomato plant provided partial protection when transferred to two other susceptible plant species. </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="6298" page="478" related-article-type="in-this-issue" vol="353" xlink:href="10.1126/science.aaf3919">478</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6298" page="442" related-article-type="in-this-issue" vol="353" xlink:href="10.1126/science.aag3111">442</jats:related-article> </jats:p>

<jats:title>Patchy landscapes select for invasiveness</jats:title> <jats:p> Invasive species are ubiquitous in human-dominated landscapes, yet we have only limited understanding of their ecological and evolutionary dynamics. Williams <jats:italic>et al.</jats:italic> used an experimental system with the model plant species <jats:italic>Arabidopsis thaliana</jats:italic> to examine how evolution affects the spread of plant populations through landscapes of varying patchiness. Plant height and dispersal ability evolved more rapidly in patchier experimental landscapes, suggesting that fragmentation can select for more rapid invasion velocity. Hence, evolution may need to be taken into account in predictions of future invasion rates. </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="6298" page="482" related-article-type="in-this-issue" vol="353" xlink:href="10.1126/science.aaf6268">482</jats:related-article> </jats:p>

<jats:p> The determinants that specify the genomic targets of Polycomb silencing complexes are still unclear. Polycomb silencing of <jats:italic>Arabidopsis</jats:italic> <jats:italic>FLOWERING LOCUS C</jats:italic> ( <jats:italic>FLC</jats:italic> ) accelerates flowering and involves a cold-dependent epigenetic switch. Here we identify a single point mutation at an intragenic nucleation site within <jats:italic>FLC</jats:italic> that prevents this epigenetic switch from taking place. The mutation blocks nucleation of plant homeodomain–Polycomb repressive complex 2 (PHD-PRC2) and indicates a role for the transcriptional repressor VAL1 in the silencing mechanism. VAL1 localizes to the nucleation region in vivo, promoting histone deacetylation and <jats:italic>FLC</jats:italic> transcriptional silencing, and interacts with components of the conserved apoptosis- and splicing-associated protein (ASAP) complex. Sequence-specific targeting of transcriptional repressors thus recruits the machinery for PHD-PRC2 nucleation and epigenetic silencing. </jats:p>

<jats:title>Lichens assemble in three parts</jats:title> <jats:p> Lichen growth forms cannot be recapitulated in the laboratory by culturing the plant and fungal partners together. Spribille <jats:italic>et al.</jats:italic> have discovered that the classical binary view of lichens is too simple. Instead, North American beard-like lichens are constituted of not two but three symbiotic partners: an ascomycetous fungus, a photosynthetic alga, and, unexpectedly, a basidiomycetous yeast. The yeast cells form the characteristic cortex of the lichen thallus and may be important for its shape. The yeasts are ubiquitous and essential partners for most lichens and not the result of lichens being colonized or parasitized by other organisms. </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="6298" page="488" related-article-type="in-this-issue" vol="353" xlink:href="10.1126/science.aaf8287">488</jats:related-article> </jats:p>

<jats:title>Plasmid copy number promotes plague</jats:title> <jats:p> The virulence of the plague bacterium, <jats:italic>Yersinia pestis</jats:italic> , is encoded on a plasmid. Normally, the bacterium only tolerates one copy of the plasmid, which provides the molecular machinery for injecting toxins into host cells. Wang <jats:italic>et al.</jats:italic> have found that <jats:italic>Y. pestis</jats:italic> can only be pathogenic if plasmid numbers are boosted and express enough protein components to assemble a functional virulence apparatus. Problematically, the synthetic activity of the plasmid has such a high metabolic cost that it can impede growth. Thus, the bacterium only allows the plasmid to replicate when it senses a potential host cell. </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="6298" page="492" related-article-type="in-this-issue" vol="353" xlink:href="10.1126/science.aaf7501">492</jats:related-article> </jats:p>

<jats:title>Mom's diet affects growth</jats:title> <jats:p> Nutrition is important during development. This appears to be true even in utero, with potential long-lasting effects on adult phenotype and disease. Epigenetic factors are prime suspects in identifying the corresponding molecular mechanism because they can be maintained throughout cell division. Holland <jats:italic>et al.</jats:italic> show in mice that in utero nutritional deficits influence offspring growth through epigenetic states at multicopy ribosomal DNA elements. This effect is influenced by the genetic variation that naturally exists within the ribosomal RNA. </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="6298" page="495" related-article-type="in-this-issue" vol="353" xlink:href="10.1126/science.aaf7040">495</jats:related-article> </jats:p>

<jats:title>Near Eastern genomes from Iran</jats:title> <jats:p> The genetic composition of populations in Europe changed during the Neolithic transition from hunting and gathering to farming. To better understand the origin of modern populations, Broushaki <jats:italic>et al.</jats:italic> sequenced ancient DNA from four individuals from the Zagros region of present-day Iran, representing the early Neolithic Fertile Crescent. These individuals unexpectedly were not ancestral to early European farmers, and their genetic structures did not contribute significantly to those of present-day Europeans. These data indicate that a parallel Neolithic transition probably resulted from structured farming populations across southwest Asia. </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="6298" page="499" related-article-type="in-this-issue" vol="353" xlink:href="10.1126/science.aaf7943">499</jats:related-article> </jats:p>

<jats:title>Zooming in on the Zika virus protease</jats:title> <jats:p> The lack of a vaccine or antiviral drugs to combat the Zika virus has scientists scrambling to identify and better characterize potential drug targets. One attractive candidate is the NS2B/NS3 viral protease, which, together with host cell proteases, cleaves the viral polyprotein into the individual proteins required for viral replication. Lei <jats:italic>et al.</jats:italic> report the crystal structure of this protease bound to a peptido-mimetic inhibitor. The structure reveals key interactions that probably contribute to the high catalytic efficiency of this enzyme relative to other flaviviruses, indicating promising starting points for drug design. </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="6298" page="503" related-article-type="in-this-issue" vol="353" xlink:href="10.1126/science.aag2419">503</jats:related-article> </jats:p>

<jats:title>Maturation and inhibition of HIV-1</jats:title> <jats:p> HIV-1 undergoes a two-step assembly process controlled largely by a single region of its Gag protein. Schur <jats:italic>et al.</jats:italic> determined a complete atomic model for this region within an assembled Gag protein lattice using cryo-electron tomography together with subtomogram averaging. Amino acids from different parts of multiple Gag molecules come together to form an intricate network of interactions that drive HIV-1 assembly. The final step of maturation into the infectious HIV-1 virus is controlled by structural changes in Gag that alter the accessibility of the final cleavage site to the viral protease. </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="6298" page="506" related-article-type="in-this-issue" vol="353" xlink:href="10.1126/science.aaf9620">506</jats:related-article> </jats:p>