Research, Research Reports
Knocking out histidine ammonia-lyase by using CRISPR-Cas9 abolishes histidine role in the bioenergetics and the life cycle of Trypanosoma cruzi
Janaína de Freitas Nascimento1, María Julia Barisón1, Gabriela Torres Montanaro1, Letícia Marchese1, Rodolpho Ornitz Oliveira Souza1, Letícia Sophia Silva2, Alessandra Aparecida Guarnieri2 and Ariel Mariano Silber1
Recent studies have highlighted the importance of this pathway in ATP production, redox balance, and the maintenance of cellular homeostasis in T. cruzi. In this work, we focus on the first step of the histidine degradation pathway, which is performed by the enzyme histidine ammonia lyase. Here we determined the kinetic and biochemical parameters of the T. cruzi histidine ammonia-lyase.
Dissecting the cell cycle regulation, DNA damage sensitivity and lifespan effects of caffeine in fission yeast
John-Patrick Alao1, Juhi Kumar1, Despina Stamataki2 and Charalampos Rallis1
Our findings show that caffeine accelerates mitotic division and is beneficial for CLS through AMPK. Direct pharmacological targeting of AMPK may serve towards healthspan and lifespan benefits beyond yeasts, given the highly conserved nature of this key regulatory cellular energy sensor.
Uga3 influences nitrogen metabolism in Saccharomyces cerevisiae by modulating arginine biosynthesis
Nicolás Urtasun1,2,a, Sebastián Aníbal Muñoz1,a, Martín Arán3 and Mariana Bermúdez-Moretti1
Nitrogen metabolism in Saccharomyces cerevisiae is tightly regulated to optimize the utilization of available nitrogen sources. Uga3 is a known transcription factor involved in the gamma-aminobutyric acid (GABA) pathway; however, its broader role in nitrogen metabolism remains unclear.
An adenine model of inborn metabolism errors alters TDP-43 aggregation and reduces its toxicity in yeast revealing insights into protein misfolding diseases
Sangeun Park, Sei-Kyoung Park, Peter Blair and Susan W. Liebman
This work offers new insights into the potential interactions between me-tabolite-based amyloids and pathological protein aggregates, with broad implications for understanding protein misfolding diseases.
Microbiota and metabolome dynamics induced by Shiga toxin-producing E. coli in an in vitro model of an infant’s colon
Mariana Izquierdo1,a, Deborah O’Sullivan2,a, Ophélie Uriot2, Morgane Brun2, Claude Durif2, Sylvain Denis2, Pablo Gallardo1, Cormac G M Gahan3-5, Lucie Etienne-Mesmin2, Stéphanie Blanquet-Diot2,b and Mauricio J. Farfan1.b
This study provides new evidence of the impact of EHEC in the microbiota and metabolome dynamics in an in vitro gut model that could be useful in understanding their physiopathology in this at-risk population, considering inter-individual variabilities in gut microbiota.
Ampicillin treatment in persister cell studies may cause non-physiological artifacts
Michel Fasnacht1,2, Hena Comic1,2, Isabella Moll1,2
This study shows at the example of L2 how insufficient purification of ampicillin persister cells can lead to the generation of non-physiological artifacts and provides a novel tool to improve the removal of residual cell debris.
Clostridium scindens promotes gallstone formation by inducing intrahepatic neutrophil extracellular traps through CXCL1 produced by colonic epithelial cells
Wenchao Yao1,a, Yuanhang He2,3,a, Zhihong Xie2,3, Qiang Wang2,3, Yang Chen2,4, Jingjing Yu2,3, Xuxu Liu2,3, Dongbo Xue2,3 , Liyi Wang2,3 and Chenjun Hao2,3
Through in vivo and in vitro experiments, we validated the reliability of C. scindens stimulating colonic epithelial cells to produce TLR2, activating the NF-κB signaling pathway, promoting CXCL1 expres-sion, and inducing intrahepatic neutrophil NETosis, which may be associated with gallstone formation.
Integrative Omics reveals changes in the cellular landscape of peroxisome-deficient pex3 yeast cells
Tjasa Kosir1,a, Hirak Das2,a, Marc Pilegaard Pedersen1, Ann-Kathrin Richard2, Marco Anteghini3,4, Vitor Martins dos Santos4,5, Silke Oeljeklaus2, Ida J. van der Klei1 and Bettina Warscheid2
To uncover the consequences of peroxisome deficiency, we compared Saccharomyces cerevisiae wild-type with pex3 cells, which lack peroxisomes, employing quantitative proteomics and transcriptomics technologies.
Microwave-assisted preparation of yeast cells for ultrastructural analysis by electron microscopy
Moritz Mayera, Christina Schuga, Stefan Geimer, Till Klecker and Benedikt Westermann
Budding yeast Saccharomyces cerevisiae is widely used as a model organism to study the biogenesis and architecture of organellar membranes, which can be visualized by transmission electron microscopy (TEM).
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).
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.