The ULK1-FBXW5-SEC23B nexus controls autophagy

In response to nutrient deprivation, the cell mobilizes an extensive amount of membrane to form and grow the autophagosome, allowing the progression of autophagy. By providing membranes and stimulating LC3 lipidation, COPII (Coat Protein Complex II) promotes autophagosome biogenesis. Here, we show that the F-box protein FBXW5 targets SEC23B, a component of COPII, for proteasomal degradation and that this event limits the autophagic flux in the presence of nutrients. In response to starvation, ULK1 phosphorylates SEC23B on Serine 186, preventing the interaction of SEC23B with FBXW5 and, therefore, inhibiting SEC23B degradation. Phosphorylated and stabilized SEC23B associates with SEC24A and SEC24B, but not SEC24C and SEC24D, and they re-localize to the ER-Golgi intermediate compartment, promoting autophagic flux. We propose that, in the presence of nutrients, FBXW5 limits COPII-mediated autophagosome biogenesis. Inhibition of this event by ULK1 ensures efficient execution of the autophagic cascade in response to nutrient starvation.Fil: Jeong, Yeon-Tae. Nyu School Of Medicine;Fil: Simoneschi, Daniele. Nyu School Of Medicine;Fil: Keegan, Sarah. Nyu School Of Medicine;Fil: Melville, David. University of California at Berkeley; Estados UnidosFil: Adler, Natalia Sol. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Saraf, Anita. Universidad Austral; ArgentinaFil: Florens, Laurence. Stowers Institute For Medical Research;Fil: Washburn, Michael P.. Stowers Institute For Medical Research;Fil: Cavasotto, Claudio Norberto. University Of Kansas Medical Center;Fil: Fenyö, David. Stowers Institute For Medical Research;Fil: Cuervo, Ana-Maria. Universidad Austral; ArgentinaFil: Rossi, Mario. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Pagano, Michele. Nyu School Of Medicine

Comparison of seven prognostic tools to identify low-risk pulmonary embolism in patients aged <50 years

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The ‘truck-driver’ effect in leaf-cutting ants: how individual load influences the walking speed of nest-mates

The foraging behaviour of social insects is highly flexible because it depends on the interplay between individual and collective decisions. In ants that use foraging trails, high ant flow may entail traffic problems if different workers vary widely in their walking speed. Slow ants carrying extra‐large loads in the leaf‐cutting ant Atta cephalotes L. (Hymenoptera: Formicidae) are characterized as ‘highly‐laden’ ants, and their effect on delaying other laden ants is analyzed. Highly‐laden ants carry loads that are 100% larger and show a 50% greater load‐carrying capacity (i.e. load size/body size) than ‘ordinary‐laden’ ants. Field manipulations reveal that these slow ants carrying extra‐large loads can reduce the walking speed of the laden ants behind them by up to 50%. Moreover, the percentage of highly‐laden ants decreases at high ant flow. Because the delaying effect of highly‐laden ants on nest‐mates is enhanced at high traffic levels, these results suggest that load size might be adjusted to reduce the negative effect on the rate of foraging input to the colony. Several causes have been proposed to explain why leaf‐cutting ants cut and carry leaf fragments of sizes below their individual capacities. The avoidance of delay in laden nest‐mates is suggested as another novel factor related to traffic flow that also might affect load size selection The results of the presennt study illustrate how leaf‐cutting ants are able to reduce their individual carrying performance to maximize the overall colony performance.Fil: Farji Brener, Alejandro Gustavo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina. Universidad Nacional del Comahue. Centro Regional Universitario Bariloche. Laboratorio de Ecotono; ArgentinaFil: Chinchilla, Federico A.. Universidad de Costa Rica. Estación Biológica Palo Verde; Costa RicaFil: Seth, Rifkin. Universidad de Puerto Rico; Puerto RicoFil: Sanchez Cuervo, Ana Maria. Universidad de Puerto Rico; Puerto RicoFil: Triana, Emilia. Universidad de Costa Rica. Escuela de Biología; Costa RicaFil: Quiroga, Verónica Andrea. Universidad Nacional de Salta; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Biología Subtropical. Universidad Nacional de Misiones. Instituto de Biología Subtropical; ArgentinaFil: Giraldo, Paola. Universidad Nacional de Caldas; Colombi

Laboratorio virtual en Biotecnología: aplicación y evaluación

La implementación de prácticas virtuales mediante plataformas de simulación experimental en los estudios de máster en el área de la Biotecnología y otras áreas afines de grado, con el fin de avanzar en la digitalización e internacionalización de las asignaturas, evaluando diferentes recursos de varias plataformas comerciales y abierta

ScipionTomo: Towards cryo-electron tomography software integration, reproducibility, and validation

International audienceImage processing in cryogenic electron tomography (cryoET) is currently at a similar state as Single Particle Analysis (SPA) in cryogenic electron microscopy (cryoEM) was a few years ago. Its data processing workflows are far from being well defined and the user experience is still not smooth. Moreover, file formats of different software packages and their associated metadata are not standardized, mainly since different packages are developed by different groups, focusing on different steps of the data processing pipeline. The Scipion framework, originally developed for SPA (de la Rosa-Trevín et al., 2016), has a generic python workflow engine that gives it the versatility to be extended to other fields, as demonstrated for model building (Martínez et al., 2020). In this article, we provide an extension of Scipion based on a set of tomography plugins (referred to as ScipionTomo hereafter), with a similar purpose: to allow users to be focused on the data processing and analysis instead of having to deal with multiple software installation issues and the inconvenience of switching from one to another, converting metadata files, managing possible incompatibilities, scripting (writing a simple program in a language that the computer must convert to machine language each time the program is run), etcetera. Additionally, having all the software available in an integrated platform allows comparing the results of different algorithms trying to solve the same problem. In this way, the commonalities and differences between estimated parameters shed light on which results can be more trusted than others. ScipionTomo is developed by a collaborative multidisciplinary team composed of Scipion team engineers, structural biologists, and in some cases, the developers whose software packages have been integrated. It is open to anyone in the field willing to contribute to this project. The result is a framework extension that combines the acquired knowledge of Scipion developers in close collaboration with third-party developers, and the ondemand design of functionalities requested by beta testers applying this solution to actual biological problems