Catálogo de publicaciones - revistas

<jats:title>Relaying information on DNA tiles</jats:title> <jats:p> Arrays of modular DNA units can relay information by transforming their internal shape in response to binding of DNA trigger strands. Song <jats:italic>et al.</jats:italic> synthesized rectangular arrays of double-stranded DNA (see the Perspective by Yang and Lin). Transient square configurations transform into two stable rectangular structures by pinching across a pair of opposing vertices. Binding of DNA trigger strands causes switching into the alternative stable configuration. The tiles thus create a cascade of transformations along a particular pathway, thereby transmitting information about where binding occurred. </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="6349" page="eaan3377" related-article-type="in-this-issue" vol="357" xlink:href="10.1126/science.aan3377">eaan3377</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6349" page="352" related-article-type="in-this-issue" vol="357" xlink:href="10.1126/science.aao0599">352</jats:related-article> </jats:p>

<jats:title>A close-up view inside the nucleus</jats:title> <jats:p> The nuclei of human cells contain 2 meters of genomic DNA. How does it all fit? Compaction starts with the DNA wrapping around histone octamers to form nucleosomes, but it is unclear how these further compress into mitotic chromosomes. Ou <jats:italic>et al.</jats:italic> describe a DNA-labeling method that allows them to visualize chromatin organization in human cells (see the Perspective by Larson and Misteli). They show that chromatin forms flexible chains with diameters between 5 and 24 nm. In mitotic chromosomes, chains bend back on themselves to pack at high density, whereas during interphase, the chromatin chains are more extended. </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="6349" page="eaag0025" related-article-type="in-this-issue" vol="357" xlink:href="10.1126/science.aag0025">eaag0025</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6349" page="354" related-article-type="in-this-issue" vol="357" xlink:href="10.1126/science.aao1893">354</jats:related-article> </jats:p>

<jats:p> Despite remarkable advances in HIV treatment and prevention, the limited political will and leadership in many countries—particularly in West and Central Africa and Eastern Europe—have fallen short of translating these gains into action. As a result, nearly 2 million infections occurred in 2016, creating a situation that is challenging to counter. This week in Paris, the International AIDS Society (IAS) convened researchers, health experts, and policy-makers to discuss the global state of this epidemic. It has been more than three decades since AIDS was clinically observed and associated with HIV infection. Since then, HIV has accounted for 35 million deaths worldwide. Today, about 37 million people are infected. IAS and the French Research Agency on HIV and Viral Hepatitis (ANRS) have now released the Paris Statement ( <jats:ext-link xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="uri" xlink:href="http://www.ias2017.org/The-Paris-Statement-HIV-Science-Matters">www.ias2017.org/The-Paris-Statement-HIV-Science-Matters</jats:ext-link> ) to remind world leaders why HIV science matters, how it should be strengthened, and why it should be funded globally and durably so that new evidence can be translated into policy. </jats:p>

<jats:p>A roundup of weekly science policy and related news.</jats:p>

<jats:p>Budget cuts and firings threaten Ecuador's plans for an academic powerhouse.</jats:p>