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<jats:title>Push Me, Release, Pull You</jats:title> <jats:p> In eukaryotic cells, nearly all long-distance transport of cargos is carried out by the microtubule-based motors kinesin and dynein. These opposite-polarity motors move cargos bidirectionally so that they reach their cellular destinations with spatial and temporal specificity. To understand transport by motor ensembles, <jats:bold> Derr <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="662" related-article-type="in-this-issue" vol="338" xlink:href="10.1126/science.1226734">662</jats:related-article> , published online 11 October; see the Persective by <jats:bold> <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6107" page="626" related-article-type="in-this-issue" vol="338" xlink:href="10.1126/science.1230818">Diehl</jats:related-article> </jats:bold> ) used a DNA scaffold for building an artificial cargo that could be programmed to bind different numbers and types of molecular motors with defined geometry. A cargo with multiple copies of the same motor was transported with minimal interference, suggesting that similar-polarity motors can coordinate without the need for additional cellular factors. However, ensembles of opposite-polarity motors frequently engaged in a sort of “tug of war,” which could only be resolved by releasing one motor from the microtubule track. Thus, within the cell, it is likely that regulation is required for bidirectional transport. </jats:p>

<jats:title>Symportin Synchrony</jats:title> <jats:p> Ribosomes, the macromolecular machines responsible for protein synthesis, function in the cytoplasm but are assembled in the nucleus. Ribosomal proteins must be imported into the nucleus, but how this is coordinated with assembly is unclear. <jats:bold> Kressler <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="666" related-article-type="in-this-issue" vol="338" xlink:href="10.1126/science.1226960">666</jats:related-article> ) report that two 5S rRNA binding proteins are coimported into the nucleus. They identify a transport adaptor, which they term symportin (Syo1), that binds simultaneously to Rpl5 and Rpl11. Syo1 also interacts with the import receptor Kap104, which facilitates import of the Syo1-Rpl5-Rpl11 complex. Synchronous nuclear transport may be more generally used to coordinate assembly processes. </jats:p>

<jats:title>PolII Goes Loopy</jats:title> <jats:p> To execute their function, genes must be transcribed into RNA, often by RNA polymerase II (PolII), which binds at the 5′ end of genes and therefore transcribes through the coding region to make messenger RNA. But, presented with nucleosome-depleted chromatin, PolII will, wastefully, initiate transcription nonspecifically and bidirectionally away from the gene. Noting that actively transcribed genes often form loops, such that their 5′ and 3′ ends are juxtaposed. <jats:bold> Tan-Wong <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="671" related-article-type="in-this-issue" vol="338" xlink:href="10.1126/science.1224350">671</jats:related-article> , published online 27 September; see the Perspective by <jats:bold> <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6107" page="624" related-article-type="in-this-issue" vol="338" xlink:href="10.1126/science.1230576">Hampsey</jats:related-article> </jats:bold> ) showed that PolII's propensity for promiscuous bidirectional transcription is reined in by gene loop formation. </jats:p>

<jats:title>Ocean Monarchs</jats:title> <jats:p> It is hard to grasp that the unseen microorganisms of the oceans are the most productive on the planet, at orders of magnitude greater than sharks and whales or even terrestrial forests. The plankton is thus a major contributor to the geochemical cycles that are currently under pressure from climate change. <jats:bold>Stocker</jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" page="628" related-article-type="in-this-issue" vol="338" xlink:href="10.1126/science.1208929">628</jats:related-article> ) reviews the state of knowledge of the web of myriad ephemeral microenvironments within the ocean's bulk and how microorganisms respond to the ever-shifting chemical spectrum. To this end, <jats:bold>Taylor and Stocker</jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" page="675" related-article-type="in-this-issue" vol="338" xlink:href="10.1126/science.1219417">675</jats:related-article> ) report experiments on the effects of turbulence on nutrient uptake by chemotactic marine bacteria. They propose that turbulence favors motile bacteria that adopt an optimal foraging strategy, which trades off the relative high cost of motility to gain the benefits of plumes of nutrients by zipping between them at optimized speeds. Scaled up, such apparently “micro” behavior will influence the rate of remineralization of dissolved organic matter and in turn will feed into global patterns of geochemical cycling. </jats:p>

<jats:title>Epigenetic Inheritance</jats:title> <jats:p> A long-standing question is whether and how stem cells maintain their epigenetic information. Knowing that many types of stem cells undergo asymmetric cell divisions, <jats:bold> Tran <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="679" related-article-type="in-this-issue" vol="338" xlink:href="10.1126/science.1226028">679</jats:related-article> ) probed the asymmetric division of <jats:italic>Drosophila</jats:italic> male germline stem cells and found that preexisting histones were selectively segregated to the stem cell, whereas new histones were enriched in the daughter cell that underwent differentiation. By contrast, asymmetric histone distribution was not seen in progenitor cells. This study suggests that stem cells retain preexisting canonical histones during asymmetric cell divisions in vivo. </jats:p>

<jats:title>Poor Choices</jats:title> <jats:p> Two categories of reasons for why poor people make economically unsound choices, such as obtaining a payday loan at an extraordinarily high rate of interest, reflect, first, the environment: Poor people are more likely to be living in poor neighborhoods with higher rates of crime and lower rates of social services. Second, they reflect the individual: People are poor in part because of their own psychological dispositions toward impatience and impulsiveness. For both cases, obtaining causal evidence in controlled experiments has been challenging. <jats:bold> Shah <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="682" related-article-type="in-this-issue" vol="338" xlink:href="10.1126/science.1222426">682</jats:related-article> ; see the Perpective by <jats:bold> <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6107" page="617" related-article-type="in-this-issue" vol="338" xlink:href="10.1126/science.1230292">Zwane</jats:related-article> </jats:bold> ) propose a third category of reasons whereby being poor exerts a bias on cognitive processes and provide evidence for it in laboratory experiments performed in scenarios of scarcity. </jats:p>

<jats:p>The show includes delaying quantum decisions, perpetuating poverty, growing global universities, 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>

<jats:p> This issue of <jats:italic>Science</jats:italic> includes the program of the 2013 AAAS Annual Meeting. The theme of the AAAS Annual Meeting in Boston, 14 to 18 February 2013, is "The Beauty and Benefits of Science." </jats:p> <jats:p> A <jats:ext-link xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="uri" xlink:href="http://www.sciencemag.org/cgi/reprint/338/6107/688.pdf">PDF</jats:ext-link> of the program as it appears in this issue is available here; for more information on the meeting (including registration forms and information on accommodations), please visit <jats:ext-link xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="uri" xlink:href="www.aaas.org/meetings/">www.aaas.org/meetings/</jats:ext-link> . </jats:p>