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

Responses of Arabica coffee (Coffea arabica L. var. Catuaí) cell suspensions to chemically induced mutagenesis and salinity stress under in vitro culture conditions

Crop improvement of Coffea arabica L. (coffee) via mutagenesis could accelerate breeding programs; thus, the present study aimed to develop an in vitro protocol using the chemical mutagens sodium azide (NaN3) and ethyl methanesulfonate (EMS) on embryogenic cell suspensions of Arabica coffee variety Catuaí and, subsequently, to evaluate the responses of the resulting mutagenized tissues to salinity stress. Embryogenic suspension cultures were incubated with 0.0, 2.5, 5.0, or 10.0 mM NaN3 or 0.0, 185.2, 370.5, or 741.0 mM EMS. As the concentration of NaN3 or EMS increased, the survival of embryogenic suspension cultures decreased compared to controls. The median lethal dose (LD50) for NaN3 was 5 mM for 15 min and for EMS it was 185.2 mM for 120 min. Embryogenic suspension cultures treated with NaN3 or EMS were cultured on selective medium supplemented with 0, 50, 100, 150, 250, or 300 mM NaCl showed that 50 mM NaCl could be used as selection pressure. Plantlet growth and total amino acid content were affected by NaCl stress; some mutants had longer shoots and higher amino acid content than controls. Random amplified polymorphic DNA (RAPD) analysis was performed to determine whether the NaN3 or EMS treatments could induce genetic variability and resulted in identifiable polymorphic markers. A total of 18 10-mer primers were used to amplify genomic DNA of putative mutant and non-mutant arabica coffee embryogenic cultures and produced 50 scorable bands, of which 22% were polymorphic.Universidad de Costa Rica/[111-B5-140]/UCR/Costa RicaUCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de Biologí

Humulus lupulus L., a very popular beer ingredient and medicinal plant: overview of its phytochemistry, its bioactivity, and its biotechnology

National audienceHumulus lupulus L. (Cannabaceae), commonly named hop, is widely grown around the world for its use in the brewing industry. Its female inflorescences (hops) are particularly prized by brewers because they produce some secondary metabolites that confer bitterness, aromas and antiseptic properties to the beer. These sought-after metabolites include terpenes and sesquiterpenes, found in essential oil, but also prenylated phenolic compounds, mainly acylphloroglucinols (bitter acids) from the series of alpha-acids (humulone derivatives). These metabolites have shown numerous biological activities, including among others, antimicrobial, sedative and estrogenic properties. This review provides an inventory of hop's chemistry, with an emphasis on the secondary metabolites and their biological activities. These compounds of biological interest are essentially produced in female inflorescences, while other parts of the plant only synthetize low quantities of them. Lastly, our article provides an overview of the research in plant biotechnology that could bring alternatives for hops metabolites production