Catálogo de publicaciones - revistas

<jats:p>The physical sciences have alternated between revolutions driven by new ideas and explorations driven by new tools.</jats:p>

<jats:p>Recognition of DNA as the carrier of information created a new fundamental dimension for viewing the natural world.</jats:p>

<jats:p>State-of-the-art molecular and morphological phylogenies for lizards differ fundamentally.</jats:p>

<jats:p>A transcriptional repressor switches to an activator function in an aggressive form of prostate cancer.</jats:p>

<jats:p>A drug that improves production of dystrophin protein reduces disease severity in a mouse model of Duchenne muscular dystrophy.</jats:p>

<jats:p>The movement of a palladium catalyst for a Heck reaction ultimately creates a ketone group far from the site of carbon-carbon bond formation.</jats:p>

<jats:p>Small gold clusters catalyze water addition to alkynes at the high efficiencies required for bulk industrial applications.</jats:p>

<jats:title>Long Noncoding RNAs</jats:title> <jats:p> The past 5 years have uncovered thousands of long (&gt;100 nucleotides) noncoding RNAs (lncRNAs) outpacing our understanding of their functions and mechanisms in regulating the genome. <jats:bold>Lee</jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" page="1435" related-article-type="in-this-issue" vol="338" xlink:href="10.1126/science.1231776">1435</jats:related-article> ) reviews the known and suspected means by which these intriguing molecules control gene expression locally and at great distances, considers potential universal roles for lncRNAs, and warns that classifying these intriguing molecules may be quite challenging given their diversity. The very long noncoding RNA, <jats:italic>Airn</jats:italic> , silences the <jats:italic>Igf2r</jats:italic> (insulin-like growth factor 2 receptor) imprinted gene cluster in mammals. <jats:bold> Latos <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" page="1469" related-article-type="in-this-issue" vol="338" xlink:href="10.1126/science.1228110">1469</jats:related-article> ) show in mouse cells that, rather than recruiting enzymes that modify histones to repress the locus, it is the act of transcription of <jats:italic>Airn</jats:italic> (and not the <jats:italic>Airn</jats:italic> gene product) that results in the silencing. </jats:p>

<jats:title>Resolving Redundancy</jats:title> <jats:p> Many intracellular bacterial pathogens, like <jats:italic>Salmonella, Legionella</jats:italic> , and <jats:italic>Chlamydia</jats:italic> , make their homes within a host cell vacuole. Although we have cataloged many of the effector proteins secreted by these bacteria and their individual effects on host cell pathways, it is often not clear how the effectors work in concert to optimize bacterial growth. <jats:bold> O'Connor <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" page="1440" related-article-type="in-this-issue" vol="338" xlink:href="10.1126/science.1229556">1440</jats:related-article> ) tackled this complexity problem in <jats:italic>Legionella pneumophila.</jats:italic> This pathogen has an exceptionally long list of apparently redundant effector proteins to its name and, indeed, initial screening produced a library of 678 <jats:italic>Legionella</jats:italic> genes important for intracellular growth. Using bacterial mutagenesis to manipulate effector proteins and RNA interference in host cells to inhibit specific cellular membrane-trafficking pathways allowed systematic prediction by cluster analysis of sets of bacterial proteins with common targets required for intracellular growth. </jats:p>

<jats:title>So Different Yet So Similar</jats:title> <jats:p> Gamma-ray bursts (GRBs) are associated with the collapse of stars into black holes. Blazars are a class of active galaxies powered by accretion onto central black holes with masses a million to a billion times that of the Sun. <jats:bold> Nemmen <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" page="1445" related-article-type="in-this-issue" vol="338" xlink:href="10.1126/science.1227416">1445</jats:related-article> ) show that, despite tremendous differences in luminosity and black hole mass, the relativistic jets produced in GRBs and blazars follow the same correlation between the kinetic power carried by the accelerated particles and the energy radiated away in the jet, suggesting that there may be a single mechanism for producing relativistic jets. </jats:p>