Catálogo de publicaciones - revistas

<jats:title>More Glycine, Please</jats:title> <jats:p> To better characterize metabolic properties of cancer cells, <jats:bold> Jain <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="1040" related-article-type="in-this-issue" vol="336" xlink:href="10.1126/science.1218595">1040</jats:related-article> ; see the Perspective by <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6084" page="990" related-article-type="in-this-issue" vol="336" xlink:href="10.1126/science.1223066"> <jats:bold>Tomita and Kami</jats:bold> </jats:related-article> ) measured systematically the concentrations of hundreds of metabolites in cell culture medium in which 60 different cancer cell lines were growing. The fastest growing cancer cells tended to consume glycine, whereas more slowly growing cells excreted some glycine. The rapidly growing cancer cells appeared to need glycine for synthesis of purine nucleotides required for continued synthesis of DNA. Interfering with glycine metabolism slowed growth of the rapidly proliferating cancer cells. Thus, an increased dependence on glycine by rapidly growing cancer cells could potentially provide a target for therapeutic intervention. </jats:p>

<jats:title>Spring Into Flower</jats:title> <jats:p> In spring, plants respond to increasing day length and shifts in the spectrum of solar irradiance by releasing the flowering induction pathway, which includes expression of the FLOWERING LOCUS T (FT) protein. <jats:bold> Song <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="1045" related-article-type="in-this-issue" vol="336" xlink:href="10.1126/science.1219644">1045</jats:related-article> ) have now identified a trio of controls brought to bear on FT gene expression by the FKF1 (FLAVIN-BINDING, KELCH REPEAT, F-BOX 1) protein. FKF1 removes a repressor and also stabilizes the activating CONSTANS (CO) protein in the afternoons through a binding interaction enhanced by blue light—an increasing component of solar irradiation during spring. Then FKF1 itself helps to activate transcription of the CO gene. Thus, by removing the repressor and shoring up the activator, FKF1 sets flowering on its way. </jats:p>

<jats:title>Who's Who</jats:title> <jats:p> Different languages rely on distinct sets of terminology to classify relatives, such as maternal grandfather in English, and precision in language usage is a key component for successful communication (see the Perspective by <jats:bold> <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6084" page="988" related-article-type="in-this-issue" vol="336" xlink:href="10.1126/science.1222691">Levinson</jats:related-article> </jats:bold> ). <jats:bold>Kemp and Regier</jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" page="1049" related-article-type="in-this-issue" vol="336" xlink:href="10.1126/science.1218811">1049</jats:related-article> ) propose an organizing framework whereby kinship classification systems can all be seen to optimize or nearly optimize both simplicity and precision. The labels applied to kin are constructed from simple units and are precise enough to reduce confusion and ambiguity when used in communication. <jats:bold>Frank and Goodman</jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" page="998" related-article-type="in-this-issue" vol="336" xlink:href="10.1126/science.1218633">998</jats:related-article> ) show that simplicity and precision also explain how listeners correctly infer the meaning of speech in the context of referential communication. </jats:p>

<jats:title>Magnetic Sense</jats:title> <jats:p> Many species orient and navigate using aspects of Earth's magnetic field. Magnetic receptors have been found in the eyes, ears, and bills of birds, but there has been no clear evidence of the neural mechanism by which magnetic signals are translated into direction. Recording from the brainstem within conscious pigeons, <jats:bold>Wu and Dickman</jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" page="1054" related-article-type="in-this-issue" vol="336" xlink:href="10.1126/science.1216567">1054</jats:related-article> , published online 26 April; see the Perspective by <jats:bold> <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6084" page="991" related-article-type="in-this-issue" vol="336" xlink:href="10.1126/science.1223786">Winklhofer</jats:related-article> </jats:bold> ) reveal the presence of neurons in the pigeon's brain that encode the inclination angle and intensity of the geomagnetic field. Thus, pigeons—and perhaps other species—can develop an internal model of geopositional latitude to facilitate spatial orientation and navigation based on magnetoreception. </jats:p>

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

<jats:p>The show includes classifying cousins, the evolution of bad teeth, where science and comedy meet, and more.</jats:p>