Catálogo de publicaciones - revistas

<jats:title>Identifying the origin of cancer</jats:title> <jats:p> Many cancers are classified on the basis of the organ or tissue from which they originated. However, identifying the specific cells and conditions that precede tumorigenesis can help us understand and better treat the resulting disease. Nowicki-Osuch <jats:italic>et al</jats:italic> . used a single-cell approach to investigate the cell of origin for Barrett’s esophagus (BE) and the mechanisms leading to the development of esophageal adenocarcinoma (EAC) (see the Perspective by Geboes and Hoorens). Analyses of healthy human esophageal tissues, mutational lineage tracing, and organoid models revealed that BE originates from the gastric cardia and that EAC arises from undifferentiated BE cells. This analysis provides a map of the transcriptional landscape of the healthy esophagus that can be compared with mouse models of disease. —LMZ </jats:p>

<jats:title>Target site selection in CAST systems</jats:title> <jats:p> Exciting genomic engineering possibilities exist for natural integration systems called transposons, which have co-opted CRISPR/Cas systems. An unexplained feature of these systems involves how they direct insertions in a single orientation at a precise distance from the programmed target sequence. Park <jats:italic>et al</jats:italic> . show that orientation information is communicated to the transposase, TnsB, using the unidirectional growth of a helical filament made up of an AAA+ protein, TnsC. ATP hydrolysis trims the filament to a minimal unit that is marked by TniQ and defined by the Cas12k protein to provide spacing information. This finding may help future engineering of these systems for therapeutic applications. —DJ </jats:p>

<jats:title> Potato pectin falls to <jats:italic>Phytophthora</jats:italic> </jats:title> <jats:p> <jats:italic>Phytophthora infestans</jats:italic> is a plant oomycete pathogen that drove the potato famines of the 1800s and continues to afflict potato fields today. The polysaccharide pectin makes up about a third of the cell wall in potatoes. Sabbadin <jats:italic>et al</jats:italic> . identified a family of lytic polysaccharide monooxygenases (LMPOs) that cleave pectin and are upregulated in <jats:italic>P. infestans</jats:italic> during infection. Silencing the relevant LMPO gene successfully inhibited <jats:italic>P. infestans</jats:italic> infections. These findings open doors for disease intervention targets and for biotech applications. —PJH </jats:p>

<jats:title>Shielding ultracold molecules</jats:title> <jats:p> Ultracold molecules hold promise for a wide range of exciting applications. However, such applications are currently hampered by the limited number of ultracold molecular ensembles that can be created and by their short lifetimes. Anderegg <jats:italic>et al</jats:italic> . used a microwave dressing field to tune the collisional properties of calcium monofluoride molecules trapped in optical tweezers. This approach allowed a sixfold suppression of inelastic trap-loss collisions. This scheme paves the way for the creation of a variety of long-lived ultracold molecular ensembles. —YS </jats:p>

<jats:title>Tough recyclable polyacetals</jats:title> <jats:p> Cyclic acetals such as dioxolane are appealing building blocks for recyclable plastics but have proven to be difficult to polymerize controllably. Abel <jats:italic>et al</jats:italic> . show that optimal pairing of a bromomethyl ether and indium or zinc Lewis acid produces polydioxolane with high tensile strength that may be advantageous for packaging applications. Heating this plastic in strong acid easily breaks it back down to its acetal monomer, which can then be recovered by distillation from mixed plastic waste streams in high yield. —JSY </jats:p>

<jats:title>Variability time scales in active galaxies</jats:title> <jats:p> Active galactic nuclei contain a supermassive black hole (SMBH) surrounded by an accretion disk. As disk material falls toward the SMBH, it heats up enough to emit optical light. Burke <jats:italic>et al</jats:italic> . investigated how such optical emission varies over time in a sample of 67 active galaxies (see the Perspective by Lira and Arevalo). They observed a characteristic variability in timing that scaled with the SMBH mass. The results elucidate the physical processes within accretion disks and provide a method to estimate SMBH mass from optical variability observations. —KTS </jats:p>

<jats:title>The timing of land plant origins</jats:title> <jats:p> Until now, the first fossil evidence of land plants was from the Devonian era 420 million years ago. However, molecular phylogenetic evidence has suggested an earlier origin in the Cambrian. Strother <jats:italic>et al</jats:italic> . describe an assemblage of fossil spores from Ordivician deposits in Australia dating to approximately 480 million years ago (see the Perspective by Gensel). These spores are of intermediate morphology between confirmed land plant spores and earlier forms of uncertain relationship. This finding may help to resolve discrepancies between molecular and fossil data for the timing of land plant origins. —AMS </jats:p>