Catálogo de publicaciones - revistas

<jats:title>Ribosome Rescue</jats:title> <jats:p> Ribosomes stall when they reach the end of defective messenger RNAs (mRNAs). In bacteria, the most-studied ribosomal rescue pathway involves a ribonucleoprotein complex comprising tmRNA (which acts as both transfer RNA and mRNA) and the protein SmpB. In an alternative pathway, some Gram-negative bacteria contain proteins that achieve tmRNA-independent rescue. Now, <jats:bold> Neubauer <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="1366" related-article-type="in-this-issue" vol="335" xlink:href="10.1126/science.1217039">1366</jats:related-article> ) present the structure of the <jats:italic>Thermus thermophilus</jats:italic> ribosome bound to a fragment of tmRNA, SmpB, and elongation factor Tu, and <jats:bold> Gagnon <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="1370" related-article-type="in-this-issue" vol="335" xlink:href="10.1126/science.1217443">1370</jats:related-article> ) report the structure of the <jats:italic>T. thermophilus</jats:italic> ribosome in complex with an initiator tRNA, a short mRNA fragment, and the rescue factor YaeJ. Though the two rescue systems are very different, both involve a protein tail that binds in the mRNA channel. This orients the rescue apparatus to facilitate switching translation to a different message in the tmRNA system or hydrolysis of peptidyl tRNA by YaeJ. </jats:p>

<jats:title>Telling Sandpaper from Satin</jats:title> <jats:p> Pacinian corpuscles are mechano-receptors tuned to detect high-frequency, low-amplitude, signals. Found in human palm and fingertips, they are useful for discrimination of rough and smooth textures, a sensitivity seemingly amplified by the ridges of fingerprints. <jats:bold> Wende <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="1373" related-article-type="in-this-issue" vol="335" xlink:href="10.1126/science.1214314">1373</jats:related-article> , published online 16 February) identified a mutation in humans that disrupts this sensitivity to texture, but leaves other facets of touch, such as tactile spatial acuity, intact. </jats:p>

<jats:title>Diversity in Immune Adversity</jats:title> <jats:p> <jats:italic>Streptococcus pneumoniae</jats:italic> commonly colonizes the nasopharynx and has the potential to cause life-threatening infections. Many variants of this pathogen are recognized that have subtly different capsule (an external polysaccharide coat) structures, which prompt distinct immune responses from the host and allow classification of this pathogen into serotypes. A consistent pattern of multiple coexisting serotypes occurs in human populations. <jats:bold>Cobey and Lipsitch</jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" page="1376" related-article-type="in-this-issue" vol="335" xlink:href="10.1126/science.1215947">1376</jats:related-article> , published online 1 March) probed the mechanisms behind serotype coexistence by developing an ecological model and feeding it data from nasopharyngeal carriage studies. </jats:p>

<jats:p>The modern world can't function without plastics, but the planet's environment may not be able to function with them. Can a new generation of polymer chemists rehabilitate these ubiquitous but environmentally troubling materials?</jats:p>

<jats:p>The show includes governing the Earth; sex, alcohol, and fruit flies; mental health in Indonesia; and more.</jats:p>

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