Research, Research Articles
Chlamydia pneumoniae is present in the dental plaque of periodontitis patients and stimulates an inflammatory response in gingival epithelial cells
Cássio Luiz Coutinho Almeida-da-Silva1, Tamer Alpagot2, Ye Zhu1, Sonho Sierra Lee3,4, Brian P. Roberts5, Shu-Chen Hung1, Norina Tang1,2 and David M. Ojcius1
This study found that Chlamydia pneumoniae is present more frequently in the dental plaque of individuals with periodontal disease, can invade human gingival epithelial cells causing inflammatory responses, and may therefore be a contributing factor to periodontal disease and a potential indicator of risk.
Simultaneous profiling of sexually transmitted bacterial pathogens, microbiome, and concordant host response in cervical samples using whole transcriptome sequencing analysis
Catherine M. O’Connell1,#, Hayden Brochu2,#, Jenna Girardi1, Erin Harrell2, Aiden Jones2, Toni Darville1, Arlene C. Seña3 and Xinxia Peng2,4
This study used total RNA sequencing to analyze cervical samples from women at high risk for STIs, revealing that host transcriptional profiles can be linked to microbiome composition and STI infections, with implications for advancing our understanding of PID and identifying potential biomarkers.
Genome-wide analysis of yeast expression data based on a priori generated co-regulation cliques
Siyuan Sima1, Lukas Schmauder1 and Klaus Richter1
The study demonstrates the use of predefined genome-wide expression cliques, derived from extensive microarray data, to effectively analyze and visualize the complete gene expression response across various cellular conditions in yeast.
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.
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.
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.
Identification of Ftr1 and Zrt1 as iron and zinc micronutrient transceptors for activation of the PKA pathway in Saccharomyces cerevisiae
March 2, 2017
We now show that the yeast high-affinity iron transporter Ftr1 and high-affinity zinc transporter Zrt1 function as transceptors for the micronutrients iron and zinc. We show that replenishment of iron to iron-starved cells or zinc to zinc-starved cells triggers within 1-2 minutes a rapid surge in trehalase activity, a well-established PKA target.
Balanced CoQ6 biosynthesis is required for lifespan and mitophagy in yeast
February 3, 2017
In brief, we show that, in yeast, Ptc7 modulates the adaptation to respiratory metabolism by dephosphorylating Coq7 to supply newly synthesized CoQ6, and by activating mitophagy to remove defective mitochondria at stationary phase, guaranteeing a proper CLS in yeast.
Mutational analysis of fructose-1,6-bis-phosphatase FBP1 indicates partially independent functions in gluconeogenesis and sensitivity to genotoxic stress
February 1, 2017
Our results support predicted vital roles of several fructose-1,6-bisphosphatase residues for enzymatic activity and led to the identification of residues indispensable for the MMS-sensitizing effect. Despite an overlap between these two properties, careful analysis revealed two mutations, Asn75 and His324, which decouple the enzymatic activity and the MMS-sensitizing effect, indicating two distinctive biological activities linked in this key gluconeogenesis enzyme.
The copper transport-associated protein Ctr4 can form prion-like epigenetic determinants in Schizosaccharomyces pombe
January 2, 2017
Ctr4 exhibits multiple features diagnostic of other fungal prions and is the first example of a prion in fission yeast. These findings suggest that transmissible protein-based determinants of traits may be more widespread among fungi.
Improvement of biochemical methods of polyP quantification
December 29, 2016
As the main output of this evaluation we propose a straightforward and robust procedure that can be used as gold standard protocol for cellular polyP purification and determination from unicellular organisms, thus providing consistency to measurements and facilitating inter-laboratory comparisons and biological interpretation of the results.
Bax mitochondrial relocation is linked to its phosphorylation and its interaction with Bcl-xL
December 5, 2016
The heterologous expression of Bax, and other Bcl-2 family members, in the yeast Saccharomyces cerevisiae, has proved to be a valuable reporter system to investigate the molecular mechanisms underlying their interaction with mitochondria. Our data provide the molecular basis for a model of dynamic equilibrium for Bax localization and activation, regulated both by phosphorylation and Bcl-xL.