Catálogo de publicaciones - revistas

<jats:title>Getting to the guts of local evolution</jats:title> <jats:p>The microbiota of mammals is a product of coevolution. However, humans exhibit a range of adaptive peculiarities that can be quite geographically specific. The human microbiota also displays a variety of community compositions and a range of overlapping and redundant metabolic characteristics that can alter host physiology. For example, lactase persistence is a genetic characteristic of European populations, but in populations lacking the lactase gene, milk sugar digestion is endowed by the microbiota instead. Suzuki and Ley review the evidence for the role that the microbiota plays in local adaptation to new and changing human circumstances.</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" related-article-type="in-this-issue" xlink:href="10.1126/science.aaz6827">eaaz6827</jats:related-article> </jats:p>

<jats:title>Tetrameric immune receptors</jats:title> <jats:p> Nucleotide-binding/leucine-rich repeat (NLR) immune receptors detect pathogen effectors and trigger a plant's immune response. Two groups have now defined the structures of two NLRs that carry Toll-like interleukin-1 receptor (TIR) domains (TIR-NLRs) (see the Perspective by Tian and Li). Ma <jats:italic>et al.</jats:italic> studied the <jats:italic>Arabidopsis thaliana</jats:italic> TIR-NLR RPP1 (recognition of <jats:italic>Peronospora parasitica</jats:italic> 1) and its response to effectors from an oomycete pathogen. Martin <jats:italic>et al.</jats:italic> studied the <jats:italic>Nicotiana benthamiana</jats:italic> TIR-NLR ROQ1 (recognition of XopQ 1) and its response to the <jats:italic>Xanthomonas</jats:italic> effector. Both groups found that these TIR-NLRs formed tetramers that, when activated by binding to the pathogen effector, exposed the active site of a nicotinamide adenine dinucleoside (NAD) hydrolase. Thus, recognition of the pathogen effector initiates NAD hydrolysis and begins the immune response. </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" related-article-type="in-this-issue" xlink:href="10.1126/science.abe3069">eabe3069</jats:related-article> , p. <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.abd9993">eabd9993</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6521" page="1163" related-article-type="in-this-issue" vol="370" xlink:href="10.1126/science.abf2833">1163</jats:related-article> </jats:p>

<jats:title>Selection enhances mutation toleration</jats:title> <jats:p> Mutations generate variability that is either neutral or subject to natural selection. Robustness is a measure of the ability to withstand deleterious mutational effects. Zheng <jats:italic>et al.</jats:italic> exposed <jats:italic>Escherichia coli</jats:italic> populations expressing a yellow fluorescent protein to strong, weak, or no selection for yellow fluorescence for four generations. They then selected these populations to a related function, green fluorescence, for four more generations. The strong selection first for yellow and then green fluorescence resulted in the most green fluorescence and the accumulation of the most mutations. This outcome likely was due to the increased foldability of the protein. Selection thus provides a threshold for mutation accumulation, but robustness maintains a buffer necessary for protein evolution. </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" related-article-type="in-this-issue" xlink:href="10.1126/science.abb5962">eabb5962</jats:related-article> </jats:p>

<jats:title>A ligand is located, at long last!</jats:title> <jats:p> Members of the Nod-like receptor (NLR) family act as intracellular sensors of infection. Once they recognize pathogen-associated molecular patterns, they assemble into signaling complexes called inflammasomes, which induce proinflammatory cytokines and pyroptotic cell death. Although rodent NLR family pyrin domain containing 1 (NLRP1) can recognize bacterial toxins and protozoan pathogens, the ligands for human NLRP1 have remained elusive. Robinson <jats:italic>et al.</jats:italic> found that human NLRP1 senses and is activated by enteroviruses. During human rhinovirus (HRV) infection, the HRV 3C protease cleaves an autoinhibitory N-terminal fragment from NLRP1, which is subsequently degraded. The NLRP1 C-terminal fragment that is released then initiates inflammasome formation. This work offers insights into immune sensing of respiratory viral infections and provides an example of the N-terminal glycine degron pathway in human innate immunity. </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" related-article-type="in-this-issue" xlink:href="10.1126/science.aay2002">eaay2002</jats:related-article> </jats:p>