Catálogo de publicaciones - revistas

<jats:title>Regulating DNA building blocks</jats:title> <jats:p> The bulding blocks of DNA, deoxynucleotide triphosphates, are synthesized by the enzyme ribonucleotide reductase (RNR). Its central role in DNA synthesis and its aberrant expression in tumors have made it an important anticancer target, but nucleoside analog inhibitors of RNR can have adverse side effects. Arnaoutov and Dasso identify IRBIT (IP <jats:sub>3</jats:sub> -receptor-binding protein released with inositol 1,4,5-trisphosphate) as an RNR-binding protein. IRBIT regulates the activity of RNR by stabilizing the inactive form bound to deoxyadenosine triphosphate in the low-affinity A site. In turn, phosophorylation of IRBIT regulates its RNR-binding activity. IRBIT provides a new target for RNR inhibition that might avoid some of the side effects of current drugs. </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="6203" page="1512" related-article-type="in-this-issue" vol="345" xlink:href="10.1126/science.1251550">1512</jats:related-article> </jats:p>

<jats:title>Establishing memory of gene repression</jats:title> <jats:p> Although cells in the body contain the same DNA content, they can display widely varying form and function among tissues. This comes about by differential gene regulation and by establishing a type of gene expression memory that is passed down during cell division to daughter cells. Gaydos <jats:italic>et al.</jats:italic> report that in nematodes, both sperm and oocytes transmit a memory of chromatin repression to embryos in the form of modified histones. During DNA replication, modified histones are passed to daughter chromatids to provide chromatin memory for a few cell divisions. Histone-modifying enzymes replenish histone modifications and provide long-term chromatin memory. </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="6203" page="1515" related-article-type="in-this-issue" vol="345" xlink:href="10.1126/science.1255023">1515</jats:related-article> </jats:p>

<jats:p>The youngest sibling in the family of 'omics fields is growing up. Maturing right behind genomics, transcriptomics, and proteomics, metabolomics is the comprehensive analysis of small molecule metabolites. Since most metabolites are generated by enzymatic proteins that result from gene expression, and metabolites give organisms their biochemical characteristics, the metabolome links genotype with phenotype. Metabolomics is still developing, though, as vendors adapt separation and detection instruments to meet its challenges and the research community interprets and integrates the complex data they are acquiring.</jats:p>

<jats:p>As we pursue bolder initiatives in space, and as China moves towards launching a permanently manned space station, gaining a clearer understanding of the impact of long-term space travel becomes essential to maintain the well-being of astronauts. Serious consideration has been given to human travel beyond low Earth orbit—where the International Space Station resides—and beyond the moon, possibly to Mars or the moons of Jupiter. Examples of groundbreaking space research currently underway in China are collected in this booklet, providing the reader with a taste of what future space exploration might look like. As Chinese scientists learn about the effects on the body and mind, they are applying their knowledge to modify equipment, improve astronaut training, and fine-tune the selection process for astronauts. Other scientists and engineers around the world will benefit, and can apply the new information to space programs in their own countries.</jats:p> <jats:p> This booklet brought to you by the <jats:italic>Science</jats:italic> /AAAS Custom Publishing Office. </jats:p> <jats:p>DOI: 10.1126/science.opms.sb0002</jats:p>

<jats:p>On this week's show: Capturing a 600-year record for a coastal ecosystem.</jats:p>

<jats:p>Microorganisms living in or on the body of a healthy human adult outnumber human cells by 10 to one. A large number of the 100 trillion microbes that compose the majority of life on Earth have coevolved a close relationship with the mammalian immune system. Therefore, by solely limiting research to either the host or bacteria, only half of the information required in microbiome studies is being seen. The symbiotic relationship of the host and resident microbiota must remain in delicate harmony to maintain a healthy body. Disruption of the microbial community can lead to an imbalance in homeostasis of the immune cells including Th17, T regulatory, and innate lymphoid cells, which can influence susceptibility of the host to a variety of health disorders including rheumatoid arthritis, obesity, inflammatory bowel disease, Crohn’s disease, diabetes, and ulcerative colitis, among others. As the number of microbiome studies grow, it is becoming increasingly clear that the host and microbiota do not operate alone. To understand the complete story, the interaction between the host and bacterial systems needs to be considered through a more holistic, systematic approach. This webinar will discuss just such an approach, examining the problem from the perspective of both the host and microbiome.</jats:p>

<jats:p>As we pursue bolder initiatives in space, and as China moves towards launching a permanently manned space station, gaining a clearer understanding of the impact of long-term space travel becomes essential to maintain the well-being of astronauts. Serious consideration has been given to human travel beyond low Earth orbit—where the International Space Station resides—and beyond the moon, possibly to Mars or the moons of Jupiter. Examples of groundbreaking space research currently underway in China are collected in this booklet, providing the reader with a taste of what future space exploration might look like. As Chinese scientists learn about the effects on the body and mind, they are applying their knowledge to modify equipment, improve astronaut training, and fine-tune the selection process for astronauts. Other scientists and engineers around the world will benefit, and can apply the new information to space programs in their own countries.</jats:p> <jats:p> This booklet brought to you by the <jats:italic>Science</jats:italic> /AAAS Custom Publishing Office. </jats:p> <jats:p>DOI: 10.1126/science.opms.sb0002</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:title>A BLUEPRINT of immune cell development</jats:title> <jats:p> To determine the epigenetic mechanisms that direct blood cells to develop into the many components of our immune system, the BLUEPRINT consortium examined the regulation of DNA and RNA transcription to dissect the molecular traits that govern blood cell differentiation. By inducing immune responses, Saeed <jats:italic>et al.</jats:italic> document the epigenetic changes in the genome that underlie immune cell differentiation. Cheng <jats:italic>et al.</jats:italic> demonstrate that trained monocytes are highly dependent on the breakdown of sugars in the presence of oxygen, which allows cells to produce the energy needed to mount an immune response. Chen <jats:italic>et al.</jats:italic> examine RNA transcripts and find that specific cell lineages use RNA transcripts of different length and composition (isoforms) to form proteins. Together, the studies reveal how epigenetic effects can drive the development of blood cells involved in the immune system. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" related-article-type="in-this-issue" xlink:href="10.1126/science.1251086">10.1126/science.1251086</jats:related-article> , <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" related-article-type="in-this-issue" xlink:href="10.1126/science.1250684">10.1126/science.1250684</jats:related-article> , <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" related-article-type="in-this-issue" xlink:href="10.1126/science.1251033">10.1126/science.1251033</jats:related-article> </jats:p>