Guidelines for the use and interpretation of assays for monitoring autophagy (4th edition)1.

In 2008, we published the first set of guidelines for standardizing research in autophagy. Since then, this topic has received increasing attention, and many scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Thus, it is important to formulate on a regular basis updated guidelines for monitoring autophagy in different organisms. Despite numerous reviews, there continues to be confusion regarding acceptable methods to evaluate autophagy, especially in multicellular eukaryotes. Here, we present a set of guidelines for investigators to select and interpret methods to examine autophagy and related processes, and for reviewers to provide realistic and reasonable critiques of reports that are focused on these processes. These guidelines are not meant to be a dogmatic set of rules, because the appropriateness of any assay largely depends on the question being asked and the system being used. Moreover, no individual assay is perfect for every situation, calling for the use of multiple techniques to properly monitor autophagy in each experimental setting. Finally, several core components of the autophagy machinery have been implicated in distinct autophagic processes (canonical and noncanonical autophagy), implying that genetic approaches to block autophagy should rely on targeting two or more autophagy-related genes that ideally participate in distinct steps of the pathway. Along similar lines, because multiple proteins involved in autophagy also regulate other cellular pathways including apoptosis, not all of them can be used as a specific marker for bona fide autophagic responses. Here, we critically discuss current methods of assessing autophagy and the information they can, or cannot, provide. Our ultimate goal is to encourage intellectual and technical innovation in the field

Epistephium chironii, a new name for Ruiz & Pav\uf3n’s Sobralia amplexicaulis (Orchidaceae)

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Photosynthetic performances of two deep‐water canopy‐forming fucoid algae across a depth gradient: Interspecific variability and short‐term adaptation to the light environment

Este artículo contiene 11 páginas, 5 tablas, 2 figuras.Deep-water canopy-forming algae Gongolaria montagnei var. compressa and Ericaria zosteroides (Fucales: Ochrophyta) co-exist in mixed populations, the first taxa dominating at the upper limit of distribution (20 m) and the second at the lower limit (40 m). This depth distribution pattern is consistent with the photosynthetic performances of both taxa, with E. zosteroides showing higher photosynthetic efficiency (α) and lower light at saturation (Ik) and compensation (Ic) than G. montagnei var. compressa. Neither photosynthesis at saturation (Pmax) nor dark respiration showed any significant change at the species level. G. montagnei v. compressa showed higher Pmax and α at 20 and 40 m, but E. zosteroides did not follow the same trend, although both Ik and Ic decreased with depth in this species, pointing to an increased capacity of E. zosteroides to show photo-adaptation. Each species maintained its Psat values when transplanted from the depth where it was dominant to the depth where it was secondary, but in the case of G. montagnei var. compressa it decreased its Psat when transplanted from 40 to 20 m and in the case of E. zosteroides it increased its Psat when transplanted from 20 to 40 m. These results point to a better photosynthetic performance of E. zosteroides than G. montagnei var. compressa at low-light conditions, information that can be used to improve success in restoration action plans.Peer reviewe

Proteostasis regulation at the endoplasmic reticulum: a new perturbation site for targeted cancer therapy

To deal with the constant challenge of protein misfolding in the endoplasmic reticulum (ER), eukaryotic cells have evolved an ER protein quality control (ERQC) mechanism that is integrated with an adaptive stress response. The ERQC pathway is comprised of factors residing in the ER lumen that function in the identification and retention of aberrantly folded proteins, factors in the ER membrane for retrotranslocation of misfolded polypeptides, and enzymes in the cytosol that degrade retrotranslocated proteins. The integrated stress response (termed ER stress or unfolded protein response, UPR) contains several signaling branches elicited from the ER membrane, which fine-tune the rate of protein synthesis and entry into the ER to match the ER folding capacity. The fitness of the cell, particularly those bearing a high secretory burden, is critically dependent on functional integrity of the ER, which in turn relies on these stress-attenuating mechanisms to maintain protein homeostasis, or proteostasis. Aberrant proteostasis can trigger cellular apoptosis, making these adaptive stress response systems attractive targets for perturbation in treatment of cell malignancies. Here, we review our current understanding of how the cell preserves ER proteostasis and discuss how we may harness the mechanistic information on this process to develop new cancer therapeutics