Catálogo de publicaciones - revistas

<jats:title>Calcium channels deliver a one-two punch</jats:title> <jats:p> To help generate long-lasting neuronal plasticity, CaV1.2 (L-type) calcium channels link electrical activity to nuclear gene expression. However, exactly how this coupling works is not fully understood. Li <jats:italic>et al.</jats:italic> developed a strategy to control two voltage-dependent signals—Ca <jats:sup>2+</jats:sup> influx and non-ionic conformational changes—separately. The combinatorial delivery of both signals was required to maximize transcription. Ca <jats:sup>2+</jats:sup> influx first mobilized the kinase CaMKII from the cytosol. This allowed subsequent voltage-dependent conformational changes to localize the kinase at CaV1.2 signaling hot spots. Abnormality of nonionic conformational signaling is associated with neurological dysfunction in Timothy syndrome, a highly penetrant form of autism-spectrum disorder. </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="6275" page="863" related-article-type="in-this-issue" vol="351" xlink:href="10.1126/science.aad3647">863</jats:related-article> </jats:p>

<jats:title>CRISPR Cas9 molecular scissors</jats:title> <jats:p> The CRISPR-associated (Cas) protein Cas9 is a molecular scissor for cutting DNA. The first step in the cutting reaction is the RNA-guided unwinding of the DNA double helix. Jiang <jats:italic>et al.</jats:italic> determined the structures of Cas9 bound to DNA unwound by the targeting RNA (see the Perspective by Chen and Bailey). Cas9 bends the DNA to allow guide RNA infiltration into the double helix. The two separated DNA strands, one bound to RNA, are subsequently positioned in the dual active sites of the protein for cutting. </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="6275" page="867" related-article-type="in-this-issue" vol="351" xlink:href="10.1126/science.aad8282">867</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6275" page="811" related-article-type="in-this-issue" vol="351" xlink:href="10.1126/science.aaf2089">811</jats:related-article> </jats:p>

<jats:title>AAA ATPase conformational high jinks</jats:title> <jats:p> The protein p97 is an AAA adenosine triphosphatase (ATPase) that uses energy from ATP hydrolysis to regulate substrates involved in intracellular protein quality control. Its role in this central process makes it a target for cancer chemotherapy. Banerjee <jats:italic>et al.</jats:italic> used cryo-electron microscopy to determine high-resolution structures for multiple conformational states of this dynamic macromolecular machine. They also determined the structure of the ADP-bound state bound to an inhibitor. The structures give insight into nucleotide-driven structural changes that drive function and show how inhibitor binding prevents these conformational changes </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="6275" page="871" related-article-type="in-this-issue" vol="351" xlink:href="10.1126/science.aad7974">871</jats:related-article> </jats:p>

<jats:title>Insight into a bacterial membrane protease</jats:title> <jats:p> Lipoproteins have key functions in many bacteria. They are synthesized in a precursor form that requires processing by enzymes that are essential in many pathogenic bacteria but have no equivalent in humans, making them potential drug targets. LspA is a key membrane protein involved in lipoprotein maturation in the bacterium <jats:italic>Pseudomonas aeruginosa</jats:italic> . Vogeley <jats:italic>et al.</jats:italic> determined the crystal structure of LspA bound to the antibiotic globomycin. Their structure and mutagenesis studies reveal how LspA processes substrate lipoproteins and indicate that globomycin inhibits the enzyme by binding to the active site. These findings should be useful in the development of new antibiotics. </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="6275" page="876" related-article-type="in-this-issue" vol="351" xlink:href="10.1126/science.aad3747">876</jats:related-article> </jats:p>

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