Vol. 05, 2018
pH homeostasis links the nutrient sensing PKA/TORC1/Sch9 ménage-à-trois to stress tolerance and longevity
Marie-Anne Deprez1,°, Elja Eskes1,°, Tobias Wilms1, Paula Ludovico2, Joris Winderickx1
In this article, Deprez et al. discuss accumulating evidence indicates that pH homeostasis plays a prominent role in the determination of ageing and longevity, thereby providing new perspectives and avenues to explore the underlying molecular mechanisms.
Guidelines and recommendations on yeast cell death nomenclature
Didac Carmona-Gutierrez1,‡,*, Maria Anna Bauer1,‡, Andreas Zimmermann1, Andrés Aguilera2, Nicanor Austriaco3, Kathryn Ayscough4, Rena Balzan5, Shoshana Bar-Nun6, Antonio Barrientos7,8, Peter Belenky9, Marc Blondel10, Ralf J. Braun11, Michael Breitenbach12, William C. Burhans13, Sabrina Büttner1,14, Duccio Cavalieri15, Michael Chang16, Katrina F. Cooper17, Manuela Côrte-Real18, Vítor Costa19–21, Christophe Cullin22, Ian Dawes23, Jörn Dengjel24, Martin B. Dickman25, Tobias Eisenberg1,26, Birthe Fahrenkrog27, Nicolas Fasel28, Kai-Uwe Fröhlich1, Ali Gargouri29, Sergio Giannattasio30, Paola Goffrini31, Campbell W. Gourlay32, Chris M. Grant33, Michael T. Greenwood34, Nicoletta Guaragnella30, Thomas Heger35, Jürgen Heinisch36, Eva Herker37, Johannes M. Herrmann38, Sebastian Hofer1, Antonio Jiménez-Ruiz39, Helmut Jungwirth1, Katharina Kainz1, Dimitrios P. Kontoyiannis40, Paula Ludovico41,42, Stéphen Manon43, Enzo Martegani44, Cristina Mazzoni45, Lynn A. Megeney46–48, Chris Meisinger49, Jens Nielsen50–52, Thomas Nyström53, Heinz D. Osiewacz54, Tiago F. Outeiro55–58, Hay-Oak Park59, Tobias Pendl1, Dina Petranovic50,51, Stephane Picot60,61, Peter Polčic62, Ted Powers63, Mark Ramsdale64, Mark Rinnerthaler65, Patrick Rockenfeller1,32, Christoph Ruckenstuhl1, Raffael Schaffrath66, Maria Segovia67, Fedor F. Severin68, Amir Sharon69, Stephan J. Sigrist70, Cornelia Sommer-Ruck1, Maria João Sousa18, Johan M. Thevelein71,72, Karin Thevissen73, Vladimir Titorenko74, Michel B. Toledano75, Mick Tuite32, F.-Nora Vögtle49, Benedikt Westermann11, Joris Winderickx76, Silke Wissing77, Stefan Wölfl78, Zhaojie J. Zhang79, Richard Y. Zhao80, Bing Zhou81, Lorenzo Galluzzi82–84,*, Guido Kroemer84–90,*, Frank Madeo1,26,*
In this review, we propose unified criteria for the definition of accidental, regulated, and programmed forms of cell death in yeast based on a series of morphological and biochemical criteria. Specifically, we provide consensus guidelines on the differential definition of terms including apoptosis, regulated necrosis, and autophagic cell death, as we refer to additional cell death routines that are relevant for the biology of yeast.
Burkholderia gladioli strain NGJ1 deploys a prophage tail-like protein for mycophagy
Rahul Kumar1, Sunil Kumar Yadav1, Durga Madhab Swain1 and Gopaljee Jha1
In this article, the authors comment on the study "A prophage tail-like protein is deployed by Burkholderia bacteria to feed on fungi" by Swain et al. (Nature Communications, 2017), discussing that a prophage tail-like protein (Bg_9562) is essential for mycophagy. The protein may help the bacteria to survive in certain ecological niches and, considering its broad-spectrum antifungal activity, may be potentially useful in biotechnological applications to control fungal diseases.
Fat storage-inducing transmembrane (FIT or FITM) proteins are related to lipid phosphatase/phosphotransferase enzymes
Matthew J Hayes1, Vineet Choudhary2, Namrata Ojha2, John JH Shin3, Gil-Soo Han4, George M. Carman4, Christopher JR Loewen3, William A Prinz2 and Timothy P Levine1
Fat storage-inducing transmembrane (FIT or FITM) proteins have been implicated in the partitioning of triacylglycerol to lipid droplets and the budding of lipid droplets from the ER. Saccharomyces cerevisiae has two FITM homologues and the presented results suggest that Scs3p and Yft2p as well as FITMs in general are lipid phosphatase/phosphotransferase (LPT) enzymes involved in an as yet unknown critical step in phospholipid metabolism.
Ras signalling in pathogenic yeasts
Daniel R. Pentland1, Elliot Piper-Brown1, Fritz A. Mühlschlegel1,2 and Campbell W. Gourlay1
In this article Pentland et al. review the roles of Ras protein function and signalling in the major human yeast pathogens Candida albicans and Cryptococcus neoformans and discuss the potential for targeting Ras as a novel approach to anti-fungal therapy.
A novel basolateral type IV secretion model for the CagA oncoprotein of Helicobacter pylori
Silja Wessler1 and Steffen Backert2
In this article, the authors comment on the study "Helicobacter pylori Employs a Unique Basolateral Type IV Secretion Mechanism for CagA Delivery" by Tegtmeyer et al. (Cell Host Microbe, 2017), discussing that the finding of a T4SS receptor suggests the presence of a sophisticated control mechanism for the injection of CagA and the possible impact of this novel signaling cascade on pathogenesis during infection with Helicobacter pylori.
Yeast quiescence exit swiftness is influenced by cell volume and chronological age
Damien Laporte1, Laure Jimenez1, Laëtitia Gouleme1, Isabelle Sagot1
Quiescence exit swiftness is crucial not only for micro-organisms in competition for an environmental niche, such as yeast, but also for the maintenance of tissue homeostasis in multicellular species. Here, Laporte et al. explore the effect of replicative and chronological age on Saccharomyces cerevisiae quiescence exit efficiency. Overall, their data illustrate that the quiescent state is a continuum evolving with time, early and deep quiescence being distinguishable by the cell’s proficiency to re-enter the proliferation cycle.
Shepherding DNA ends: Rif1 protects telomeres and chromosome breaks
Gabriele A. Fontana1, Julia K. Reinert1,2, Nicolas H. Thomä1, Ulrich Rass1
This review discusses the conserved mechanisms cells have evolved to protect DNA ends at chromosomal termini and DNA double-strand breaks (DSBs), focusing on the protein Rif1’s roles in telomere homeostasis and DSB repair in eukaryotes. It highlights the intriguing connection between Rif1's involvement in both telomere maintenance and DSB repair, and suggests that excluding end-processing factors may underlie Rif1's diverse biological functions at telomeres and chromosome breaks.
The CRISPR conundrum: evolve and maybe die, or survive and risk stagnation
Jesús García-Martínez1, Rafael D. Maldonado1, Noemí M. Guzmán1 and Francisco J. M. Mojica1,2
In this article García-Martínez et al. cover how the model bacterium Escherichia coli deals with CRISPR-Cas to tackle the major dilemma of evolution versus survival.
Microbial wars: competition in ecological niches and within the microbiome
Maria A. Bauer1, Katharina Kainz1, Didac Carmona-Gutierrez1 and Frank Madeo1,2
In this Editorial Bauer et al. provide a brief overview on microbial competition and discuss some of its roles and consequences that directly affect humans.
Metabolic disharmony and sibling conflict mediated by T6SS
Vera Troselj1 and Daniel Wall1
In this article, the authors comment on the study "Physiological Heterogeneity Triggers Sibling Conflict Mediated by the Type VI Secretion System in an Aggregative Multicellular Bacterium" by Troselj et al. (MBio, 2018) discussing that M. xanthus uses T6SS to eliminate less fit cells from their population and identified toxic effector and cognate immunity protein (TsxEI) that mediates this sibling antagonism.
Antagonism between salicylate and the cAMP signal controls yeast cell survival and growth recovery from quiescence
Maurizio D. Baroni1, Sonia Colombo2 and Enzo Martegani2
This article describes the effects of salicylate, the main metabolite of aspirin, on S. cerevisiae cells. It outlines how salicylate influences glucose transport, sugar phosphate biosynthesis, and apoptosis, particularly in MnSOD-deficient cells. Furthermore, it emphasizes the significant impact of salicylate on the exit from a quiescent state, inhibiting growth recovery and viability in long-term stationary phase cells. The passage also discusses the potential therapeutic implications of understanding the antagonistic relationship between cAMP and salicylate in targeting quiescent cancer cells with stem-like properties.
A novel basolateral type IV secretion model for the CagA oncoprotein of Helicobacter pylori
Silja Wessler1 and Steffen Backert2
In this article, the authors comment on the study "Helicobacter pylori Employs a Unique Basolateral Type IV Secretion Mechanism for CagA Delivery" by Tegtmeyer et al. (Cell Host Microbe, 2017), discussing that the finding of a T4SS receptor suggests the presence of a sophisticated control mechanism for the injection of CagA and the possible impact of this novel signaling cascade on pathogenesis during infection with Helicobacter pylori.
Microbial wars: competition in ecological niches and within the microbiome
Maria A. Bauer1, Katharina Kainz1, Didac Carmona-Gutierrez1 and Frank Madeo1,2
In this Editorial Bauer et al. provide a brief overview on microbial competition and discuss some of its roles and consequences that directly affect humans.
Exploring the mechanism of amebic trogocytosis: the role of amebic lysosomes
Allissia A. Gilmartin1 and William A. Petri, Jr1,2,3
In this article, the authors comment on the study "Inhibition of Amebic Lysosomal Acidification Blocks Amebic Trogocytosis and Cell Killing" by Gilmartin et al. (MBio, 2017), discussing the the role of amebic lysosomes in Trogocytosis, the intracellular transfer of fragments of cell material.
Retroviral integration site selection: a running Gag?
November 19, 2018
In this article, the authors comment on the study "Structural basis for spumavirus GAG tethering to chromatin" by Lesbats et al. (Proc Natl Acad Sci, 2018) that revealed that the Gag protein of the spumaretrovirus prototype foamy virus (PFV) directly interacts with the nucleosome acidic patch, acting as a chromatin tether, and its disruption leads to delocalization of viral particles and integration sites, shedding light on the importance of retroviral structural proteins in the selection of integration sites.
A humanized yeast-based toolkit for monitoring phosphatidylinositol 3-kinase activity at both single cell and population levels
November 12, 2018
In this study, a humanized yeast system for functional studies on higher eukaryotic Phosphatidylinositol 3-kinase (PI3K) was developed by restricting PI3K activity in yeast to specific plasma membrane microdomains, utilizing engineered reporters to monitor activity at a single-cell level and employing novel tools to study the performance of yeast plasma membrane (PM) microdomain-directed PI3K, revealing location-specific effects on yeast growth and endocytosis.
Insights into the host-pathogen interaction: C. albicans manipulation of macrophage pyroptosis
November 12, 2018
In this article, the authors comment on the study "High-Throughput Screening Identifies Genes Required for Candida albicans Induction of Macrophage Pyroptosis" by O’Meara et al. (MBio, 2018) that provides a comprehensive analysis of the genetic circuitry in both Candida albicans and host macrophages that leads to pyroptosis, revealing the impact of altered pyroptosis on infection, the role of pyroptosis in facilitating neutrophil accumulation at the site of C. albicans infection, and the decoupling of inflammasome priming and activation in the response to C. albicans infection, thus shedding new light on the factors governing the outcomes of this interaction.
A chemical genetic screen reveals a role for proteostasis in capsule and biofilm formation by Cryptococcus neoformans
October 31, 2018
This study demonstrates that the bipolar disorder drug lithium inhibits the formation of key virulence factors, biofilm, and polysaccharide capsule, in Cryptococcus neoformans by dysregulating the ubiquitin/proteasome system, shedding light on the impact of lithium and providing insights into potential alternative pharmaceutical approaches for combating this fungal pathogen.
A comparative approach to decipher intestinal animal-microbe associations
October 31, 2018
In this article, the authors comment on the study "Chitin-based barrier immunity and its loss predated mucus-colonization by indigenous gut microbiota" by Nakashima et al. (Nat Commun, 2018) that used comparative analyses of chordates to investigate the development of animal-microbe associations, suggesting that microbial colonization of the mucus layer over mammalian gastrointestinal epithelium was established upon the loss of ancestral chitin-based barrier immunity, providing insights into the establishment of these associations in an evolutionary context.
Nutritional and meiotic induction of transiently heritable stress resistant states in budding yeast
October 29, 2018
This study demonstrates that transient exposures to environmental stresses induce persistent states of elevated stress resistance in yeast cells, termed cellular memory, suggesting a form of epigenetic inheritance, and shows that this phenomenon occurs not only in meiotically produced spores but also in haploid cells subjected to glucose withdrawal, adding new insights into the developmentally and nutritionally induced cellular memory.
Pathways of host cell exit by intracellular pathogens
October 18, 2018
This review provides an overview of the diverse host cell exit strategies employed by intracellular-living bacterial, fungal, and protozoan pathogens, highlighting the commonalities and system-specific variations of these strategies, and discussing potential microbial molecules involved in host cell exit as targets for future intervention approaches.
Specific mutations in the permease domain of septal protein SepJ differentially affect functions related to multicellularity in the filamentous cyanobacterium Anabaena
October 16, 2018
In this study, the multifunctional roles of the SepJ protein in the multicellular function of the Anabaena filament were investigated, revealing that specific amino acids and stretches within the protein are essential for the formation of long filaments, heterocyst differentiation, and intercellular communication, shedding light on the structure and diverse functions of SepJ in the model heterocyst-forming cyanobacterium Anabaena sp. strain PCC 7120.
Trehalose-6-phosphate promotes fermentation and glucose repression in Saccharomyces cerevisiae
October 1, 2018
This study examined the capability of trehalose-6-phosphate synthase (TPS1) homologues from various species to complement the phenotypic defects of a Saccharomyces cerevisiae tps1 mutant, resulting in the classification of complementation into different groups based on metabolic patterns and fermentation capacity, shedding light on the role of TPS1 and trehalose-6-phosphate (T6P) as critical factors in sugar fermentation and glucose repression.
Exploring the mechanism of amebic trogocytosis: the role of amebic lysosomes
Allissia A. Gilmartin1 and William A. Petri, Jr1,2,3
In this article, the authors comment on the study "Inhibition of Amebic Lysosomal Acidification Blocks Amebic Trogocytosis and Cell Killing" by Gilmartin et al. (MBio, 2017), discussing the the role of amebic lysosomes in Trogocytosis, the intracellular transfer of fragments of cell material.