Research, Research Articles
A humanized yeast-based toolkit for monitoring phosphatidylinositol 3-kinase activity at both single cell and population levels
Julia María Coronas-Serna1, Teresa Fernández-Acero1, María Molina1 and Víctor J. Cid1
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.
A chemical genetic screen reveals a role for proteostasis in capsule and biofilm formation by Cryptococcus neoformans
François L. Mayer1, Eddy Sánchez-León1, James W. Kronstad1
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.
Nutritional and meiotic induction of transiently heritable stress resistant states in budding yeast
Heldder Gutierrez1, Bakhtiyar Taghizada1, and Marc D. Meneghini1
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.
Specific mutations in the permease domain of septal protein SepJ differentially affect functions related to multicellularity in the filamentous cyanobacterium Anabaena
Félix Ramos-León1, Sergio Arévalo1, Vicente Mariscal1 and Enrique Flores1
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
Rebeca L. Vicente1,2, Lucie Spina1, Jose P.L. Gómez1, Sebastien Dejean3, Jean-Luc Parrou1 and Jean Marie François1,4
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.
The translationally controlled tumor protein TCTP is involved in cell cycle progression and heat stress response in the bloodstream form of Trypanosoma brucei
Borka Jojic1, Simona Amodeo1,2 and Torsten Ochsenreiter1
This study reveals the involvement of the translationally controlled tumor protein TCTP in cell cycle regulation and heat stress response in the bloodstream form of Trypanosoma brucei, shedding light on its role in these cellular processes.
Single telomere length analysis in Ustilago maydis, a high-resolution tool for examining fungal telomere length distribution and C-strand 5’-end processing
Ganduri Swapna1, Eun Young Yu1 and Neal F. Lue1, 2
This article introduces the development of single telomere length analysis (STELA) for Ustilago maydis, a basidiomycete fungus, enabling the precise measurement of telomere lengths and distributions. The study demonstrates STELA's utility in revealing the existence of relatively short telomeres in wild-type cells, preferential loss of long telomeres in a mutant defective in telomere replication, and the characterization of telomere C-strand 5’ ends, highlighting U. maydis as a strong model for telomere research.
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.
Identification of SUMO conjugation sites in the budding yeast proteome
October 2, 2017
The authors present a proteomic study that mapped SUMO acceptor lysines in budding yeast, identifying 257 potential conjugation sites, including both known and novel substrates, and providing a significant resource for future research into the functional implications of SUMOylation in yeast.
Ydj1 governs fungal morphogenesis and stress response, and facilitates mitochondrial protein import via Mas1 and Mas2
October 2, 2017
The authors descibe the role of the Hsp40 chaperone Ydj1 in Candida albicans, noting its localization to the cytosol and mitochondrial membrane, its necessity for stress responses and filamentation, and its involvement in a protein interaction network related to co-chaperones, filamentation regulators, and mitochondrial processing peptidases, with a particular focus on the impact of Ydj1 on mitochondrial morphology, function, and the import of precursor proteins.
Farnesol inhibits translation to limit growth and filamentation in C. albicans and S. cerevisiae
September 4, 2017
Farnesol, a quorum-sensing molecule, inhibits the switch from yeast to filamentous growth in Candida albicans by impeding translation initiation, differing from fusel alcohols that affect the initiation factor eIF2B, as it disrupts mRNA interaction with the ribosome and prevents preinitiation complex formation.
Cristae architecture is determined by an interplay of the MICOS complex and the F1FO ATP synthase via Mic27 and Mic10
July 20, 2017
This article investigates the roles of MICOS subunits Mic27 and Mic10, revealing their antagonistic and cooperative interactions in crista junction formation and cristae membrane curvature, and proposes a model where F1FO-ATP synthase is connected to MICOS, influencing CJ formation.
Integrative modules for efficient genome engineering in yeast
June 5, 2017
The study introduces a set of vectors with integrative modules designed for effective genome integration into standard marker loci of Saccharomyces cerevisiae, enabling precise expression levels using various promoters and demonstrating the capability of stable multi-gene integration, which is useful for tasks like multi-color cellular imaging and metabolic engineering.
The neuroprotective steroid progesterone promotes mitochondrial uncoupling, reduces cytosolic calcium and augments stress resistance in yeast cells
May 31, 2017
Progesterone, known for its role in the reproductive system, also acts as a neurosteroid and has been suggested to aid recovery from traumatic brain injury; a study using yeast models shows that progesterone can protect against apoptosis, reduce oxidative stress and calcium spikes, and increase mitochondrial function, independent of traditional progesterone receptors or calcium transporters.
A simple microfluidic platform to study age-dependent protein abundance and localization changes in Saccharomyces cerevisiae
April 13, 2017
We have developed a user-friendly microfluidic system paired with a genetic approach to enrich and study ageing mother yeast cells, enabling the monitoring of protein abundance and localization changes during the crucial first half of their replicative lifespan, leading to the discovery of novel age-dependent protein behaviors.
Thiol trapping and metabolic redistribution of sulfur metabolites enable cells to overcome cysteine overload
March 27, 2017
In this study, researchers investigate the mechanisms for handling cysteine overload using Saccharomyces cerevisiae, finding that overexpressing the high affinity cysteine transporter, YCT1, enables yeast cells to rapidly accumulate high levels of intracellular cysteine. The study demonstrates that cells can manage potentially toxic levels of cysteine by converting it to non-reactive thiol forms and utilizing the metabolic products for cell growth.
The frequency of yeast [PSI+] prion formation is increased during chronological ageing
March 27, 2017
Aging is marked by a decline in cellular functions and the increased formation of the yeast [PSI+] prion, an altered translation termination factor, which suggests that autophagy suppresses age-related prion development. Interestingly, yeast cells that adopt the [PSI+] form exhibit better survival through aging, indicating that [PSI+] formation, linked to enhanced autophagy, may confer advantages such as reduced protein aggregation and improved cell viability.
A multigene family encoding surface glycoproteins in Trypanosoma congolense
March 2, 2017
Trypanosoma congolense, the causative agent of the most important livestock disease in Africa, expresses specific surface proteins involved in its parasitic lifestyle. By mining the T. congolense genome database, we identified a novel family of lectin-like glycoproteins (TcoClecs).