Research Articles
Temporal analysis of the autophagic and apoptotic phenotypes in Leishmania parasites
Louise Basmaciyan1, Laurence Berry2, Julie Gros3, Nadine Azas3 and Magali Casanova3
This article details a comprehensive analysis of miltefosine-induced cell death and autophagy in Leishmania major, providing criteria for clear identification of apoptotic and autophagic cells, demonstrating the sequential nature of autophagy followed by apoptosis in nutrient-deprived conditions, and cautioning against using the generic kinase inhibitor staurosporine as a Leishmania apoptosis inducer, with the aim of improving the understanding of these processes and their targeting for new anti-leishmanial drugs.
Snf1 cooperates with the CWI MAPK pathway to mediate the degradation of Med13 following oxidative stress
Stephen D. Willis1, David C. Stieg1, Kai Li Ong2, Ravina Shah1,3, Alexandra K. Strich1,4, Julianne H. Grose2 and Katrina F. Cooper1
This article explores the response of eukaryotic cells to environmental stress, highlighting the role of the conserved cyclin C-Cdk8 kinase in determining pro-survival or pro-death programs. Specifically, it discusses how oxidative stress triggers the destruction of Med13 by the SCFGrr1 ubiquitin ligase, releasing cyclin C to promote mitochondrial fission and cell death in Saccharomyces cerevisiae. Additionally, it reveals that the AMP kinase Snf1 activates a separate degron in Med13, contributing to the complex regulation of Med13 degradation following H2O2 stress through the coordination of the cell wall integrity and MAPK pathways.
Importance of polyphosphate in the Leishmania life cycle
Kid Kohl1, Haroun Zangger1, Matteo Rossi1, Nathalie Isorce1, Lon-Fye Lye2, Katherine L. Owens2, Stephen M. Beverley2, Andreas Mayer1 and Nicolas Fasel1
This article explores the importance of polyphosphate (polyP) in Leishmania parasites, emphasizing the role of the polyP polymerase VTC4 and its impact on parasite survival at higher temperatures. Additionally, it discusses the effects of VTC4 knockout in mouse infections, noting a delay in lesion formation and strong pathology in L. major VTC4 knockout, without confirmation through complementation and no alteration in L. guyanensis infections in mice with VTC4 knockdown.
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.
Spontaneous mutations in CYC8 and MIG1 suppress the short chronological lifespan of budding yeast lacking SNF1/AMPK
Nazif Maqani1,#, Ryan D. Fine1,#, Mehreen Shahid1, Mingguang Li1,2, Elisa Enriquez-Hesles1 and Jeffrey S. Smith1
Chronologically aging yeast cells are prone to adaptive regrowth, whereby mutants with a survival advantage spontaneously appear and re-enter the cell cycle in stationary phase cultures. Here, Magani et al. identified specific downstream SNF1 targets responsible for CLS extension during CR.
Production of poly-β-1,6-N-acetylglucosamine by MatAB is required for hyphal aggregation and hydrophilic surface adhesion by Streptomyces
Dino van Dissel1, Joost Willemse1, Boris Zacchetti1, Dennis Claessen1, Gerald B. Pier2, Gilles P. van Wezel1
In this article van Dissel et al. describe new insights to allow better control of liquid-culture morphology of streptomycetes, which may be harnessed to improve growth and industrial exploitation of these highly versatile natural product and enzyme producers.
Non-canonical regulation of glutathione and trehalose biosynthesis characterizes non-Saccharomyces wine yeasts with poor performance in active dry yeast production
Esther Gamero-Sandemetrio1, Lucía Payá-Tormo1, Rocío Gómez-Pastor1,3, Agustín Aranda1,2 and Emilia Matallana1,2
Several yeast species, belonging to Saccharomyces and non-Saccharomyces genera, play fundamental roles during spontaneous must grape fermentation, and recent studies have shown that mixed fermentations, co-inoculated with S. cerevisiae and non-Saccharomyces strains, can improve wine organoleptic properties. Here, Gamero-Sandemetrio et al. present findings that non-canonical regulation of glutathione and trehalose biosynthesis could cause poor fermentative performance after active dry yeast (ADY) production, as it corroborates the corrective effect of antioxidant treatments, during biomass propagation, with both pure chemicals and food-grade argan oil.
Molecular signature of the imprintosome complex at the mating-type locus in fission yeast
Célia Raimondi1, Bernd Jagla2, Caroline Proux3, Hervé Waxin4, Serge Gangloff1, Benoit Arcangioli1
Genetic and molecular studies have indicated that an epigenetic imprint at mat1, the sexual locus of fission yeast, initiates mating type switching. Here, Raimondi et al. characterized the recruitment of early players of mating type switching at the mat1 region and suggest a nucleoprotein protective structure defined as imprintosome.
Two distinct and competitive pathways confer the cellcidal actions of artemisinins
January 1, 2015
The biological actions of artemisinin (ART), an antimalarial drug derived from Artemisia annua, remain poorly understood and controversial. This article concludes that ARTs are endowed with two major and distinct types of properties: a potent and specific mitochondria-dependent reaction and a more general and less specific heme-mediated reaction. The competitive nature of these two actions could be explained by their shared source of the consumable ARTs, so that inhibition of the heme-mediated degradation pathway would enable more ARTs to be available for the mitochondrial action. These properties of ARTs can be used to interpret the divergent antimalarial and anticancer actions of ARTs.
Measurement of apoptosis by SCAN©, a system for counting and analysis of fluorescently labelled nuclei
November 26, 2014
This work reports on a system for analyses of apoptosis-like programmed cell death in fungal hyphae that is composed of several modules, which enable automatic quantification of nuclei with chromatin condensation and DNA strand break in large datasets according to nuclei-associated fluorescent markers.
Rewiring yeast acetate metabolism through MPC1 loss of function leads to mitochondrial damage and decreases chronological lifespan
November 18, 2014
This work shows that MPC1-deficient cells make up for their impairment in mitochondrial pyruvate with a metabolic rewiring which involves several intermediates of the mitochondrially localized TCA cycle and the cytosolic glyoxylate shunt but ultimately results in a pro-aging process.
Overexpression of the transcription factor Yap1 modifies intracellular redox conditions and enhances recombinant protein secretion
October 31, 2014
This article investigates the role of Yap1 during the production of recombinant secretory proteins in glucose based growth conditions in Pichia pastoris, and reports a novel role of Yap1 during ER-resident oxidative protein folding.
Functional analysis of lipid metabolism genes in wine yeasts during alcoholic fermentation at low temperature
October 29, 2014
This study confirms the importance of specific genes in growth and fermentation activity of Saccharomyces cerevisiae at low temperature.
Angiotensin II type 1 receptor blockers increase tolerance of cells to copper and cisplatin
October 24, 2014
This study reports the identification of the drug class of Angiotensin II Type 1 receptor blockers (ARBs) and shows that specific ARBs increase yeast tolerance to Cu and Cp, and affect markers of Cu-induced apoptosis. Likewise, this study finds that specific ARBs increase human cell line tolerance to Cu and decrease the prevalence of apoptotic markers.
An extensive endoplasmic reticulum-localised glycoprotein family in trypanosomatids
October 1, 2014
This work describes a novel family of type I membrane proteins ("invariant glycoproteins") and proposes them as trypanosomatid-specific ER-localised glycoproteins, with potential contributions to life cycle progression and immunity, that utilise oligomerisation as an ER retention mechanism.
Time resolved DNA occupancy dynamics during the respiratory oscillation uncover a global reset point in the yeast growth program
September 1, 2014
Using multiple approaches, this work implies a nucleosome focusing event as a key step that resets transcription during the respiratory oscillation.
Cell wall dynamics modulate acetic acid-induced apoptotic cell death of Saccharomyces cerevisiae
August 27, 2014
This work characterizes the involvement of MAPK signaling pathways in cell death induced by acetic acid in Saccharomyces cerevisiae.
Extracellular calcium triggers unique transcriptional programs and modulates staurosporine-induced cell death in Neurospora crassa
August 9, 2014
The results presented here reveal that in Neurospora crassa, extracellular Ca2+ modulates cell death and the transcriptional alterations induced by staurosporine, and lead to the identification of two novel putative Ca2+-binding proteins, encoded by the NCU08524 and NCU06607 genes.