Catálogo de publicaciones - revistas

<jats:title>For gene enhancers, less is more</jats:title> <jats:p> Weak enhancer sequences provide just the right amount of gene activity. Farley <jats:italic>et al.</jats:italic> systematically examined millions of synthetic variants of the Otx enhancer, a motif needed for gene expression in the nervous system of the sea squirt Ciona. Proper gene activity resulted when there were imperfect matches to the motif showing strongest enhancer binding and gene activation. When “optimal” motifs were incorporated, ectopic expression ensued, with aberrant gene activation outside the nervous system. </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="6258" page="325" related-article-type="in-this-issue" vol="350" xlink:href="10.1126/science.aac6948">325</jats:related-article> </jats:p>

<jats:title>Dying to impress the immune system</jats:title> <jats:p> Besides reacting to microbes, T cells can also mount immune responses to fragments of dying cells, which they encounter displayed on dendritic cells. Not all dying cells activate T cells, however, so what differentiates the dying cells that do? Yatim <jats:italic>et al.</jats:italic> studied two forms of programmed cells death: apoptosis and necroptosis. Using mouse cells in culture and mouse models of inflammatory cell death and anti-tumor immunity, they found that programmed cell death initiated T cell immunity only when the dying cells signaled through the enzyme RIPK1 and the transcription factor NF-κB. </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="6258" page="328" related-article-type="in-this-issue" vol="350" xlink:href="10.1126/science.aad0395">328</jats:related-article> </jats:p>

<jats:title>How T cells maintain their identity</jats:title> <jats:p> Although best known for their pathogen-fighting prowess, T lymphocytes also ensure that the immune response does not run amok. A subset of T cells called regulatory T cells (T <jats:sub>regs</jats:sub> ) performs this function by, for example, making sure T cells only attack pathogens and not self. T cells can exhibit plasticity in their functions in the face of an inflammatory stimulus. Kim <jats:italic>et al.</jats:italic> sought to identify the molecules that ensure the stable maintenance of T <jats:sub>regs</jats:sub> . Using genetically modified mice, they found that both CD4 <jats:sup>+</jats:sup> and CD8 <jats:sup>+</jats:sup> T <jats:sub>regs</jats:sub> require the transcription factor Helios to stably maintain their identity. </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="6258" page="334" related-article-type="in-this-issue" vol="350" xlink:href="10.1126/science.aad0616">334</jats:related-article> </jats:p>

<jats:title>A Gaulish partner in silencing transposons</jats:title> <jats:p> Small noncoding piRNAs protect animal germline genomes from devastating mutation and rearrangement caused by transposons. In fruit fly ovaries, piRNAs bind to Piwi proteins, and together they are required for the recognition and silencing of these parasitic DNA elements. Yu <jats:italic>et al.</jats:italic> show that the gene Panoramix acts downstream of the piRNA-driven recognition of transposons to silence their transcription. Panoramix does this by binding newly synthesized transposon RNAs. </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="6258" page="339" related-article-type="in-this-issue" vol="350" xlink:href="10.1126/science.aab0700">339</jats:related-article> </jats:p>

<jats:p>On this week's show: A first look at the geology and composition of Pluto's surface and a roundup of daily news stories.</jats:p>

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