Research, Research Articles
A time-resolved high-throughput screening of fission yeast deletion mutants for oxidative stress resistance
Mohammadtaha Pirsalehi, Rowshan Ara Islam, Kristal Ng, Olga Xintarakou, Peter Harold Thorpe and Charalampos Rallis
By capturing dynamic trajectories rather than static outcomes, this study exposes hidden layers of growth under oxidative stress and identifies new genetic determinants of cellular resilience in fission yeast.
Clonal spread and environmental persistence of carbapenem-resistant high-risk Pseudomonas aeruginosa in critical-care units of a Chilean national referral center for burn and trauma patients (2022)
Camila Ibarra1, Gustavo Araya2, Alhejandra Alvarez2, Leonardo Enríquez2, Carolina Arellano2, Fabricio Alarcón1, Constanza Fernández1, Claudio Vargas1, Rodrigo Vera1 and Roberto M. Vidal2
This study highlight the circulation of high-risk P. aeruginosa clones in Chile and underscore the importance of molecular epidemiology in guiding infection control, optimizing antimicrobial therapy, and mitigating the clinical and economic burden of CRPA.
The transcriptome of dendritic cells redraws the boundaries between pathogenicity and commensalism in yeast
Lisa Rizzetto1, Irene Stefanini2, Stefano Nenciarini3, Monica Di Paola3, Samantha Riccadonna1, Ivo G. Gut4,5, Marta Gut4,5, Simon Heath4,5 and Duccio Cavalieri3
Our immune system meets many fungi, but reacts strongly to only a few. The comparison of key fungal species showed that responses differ mainly in timing and not just genes, highlighting the need to rethink what makes fungi harmful vs. harmless.
Yippee-like protein Moh1 links gene expression to metabolism and selective stress resistance in Saccharomyces cerevisiae
Çağla Ece Olgun1,a, Gizem Turan Duman1,a, Gizem Güpür1, Hamit İzgi1, Mariam Huda2, Demet Çetin3, Zekiye Suludere4, Fatma Küçük Baloğlu5, Ayşe Koca Çaydaşı2 and Mesut Muyan1
This study demonstrates that the conserved yeast protein Moh1 links metabolism, gene expression, and cell structure, thereby altering cell envelope permeability and leading to selective stress responses.
Fungistatic effect of sorbic acid on yeast cells via translational repression involving eIF2α phosphorylation and formation of Ded1- and eIF2B-granules
Haruka Yoshiyama1, Wataru Nomura2 and Shingo Izawa1
The findings of this study provide new insights into the physiological effects of sorbic acid on yeast cells, specifically regarding the regulation of translation-related factors.
Occlusal types shape oral microbiome stomatotypes and metabolic landscapes: A multi-omics perspective on host-microbe interaction
Yufeng Duan1,a, Zheng Liu2,3,a, Wenting Lu1,a, Ning Zhao1, Lingjun Yuan1, Zhenxia Li1, Ting Zhou1, Shengzhao Xiao1, Dian Jing1, Xiaowen Zheng1, Wentao Shi4, Chao Liu1,*, Haixia Lu5,*, Qiang Feng6,* and Bing Fang1,*
This study reveals how occlusal types shape oral microbiome “stomatotypes” and metabolic profiles in adolescents. It offers fresh insights that host anatomy drives microecology which may be associated with personalized oral health.
Genomic epidemiology of carbapenemase-producing Klebsiella pneumoniae circulating in a Chilean tertiary-care hospital (2021–2022): Molecular characterization, resistance-virulence convergence, and clinical associations
Gustavo Araya1,2, Alhejandra Álvarez1, Carolina Arellano1, Rodrigo Bravo3, Abraham Gajardo4,5, Boris Barrera6, Francisco Silva6 and Roberto M. Vidal1
This study characterized carbapenem-resistant Kp (CR-Kp) strains isolated at the Hospital Clínico Universidad de Chile (HCUCH) 2021-2022 and explored associations with clinical characteristics.
Sugar-induced cell death (SICD) in Saccharomyces cerevisiae: insights into nitrogen-mediated rescue and apoptotic cell death pathways
Raveena Parbhudayal and Hai-Ping Cheng
This study examined mechanisms through which yeast sugar-induced cell death can be prevented. High concentrations of glucose induced a catastrophic response that was only rescued by highly preferred nitrogen sources and by preventing nuclear localization of specific cell death proteins.
TOR-dependent regulation of the yeast homolog of the juvenile Batten Disease-associated gene CLN3
Vijaykumar Pillalamarri1, Samuel W.M. Gatesy1, Amanda E. Grassel1, Lucienna Wolf1, Justin P. Whalley2 and David M. Mueller1,*
This study identifies conditions and genes that induce BTN1 expression in yeast. We show that BTN1 expression is regulated by translational control and by the mTOR1 pathway. An understanding of when and why BTN1 expression will aid in understanding the expression of CLN3, which may be helpful in the treatment of this devastating disease.
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.
Impact of histone H4K16 acetylation on the meiotic recombination checkpoint in Saccharomyces cerevisiae
December 4, 2016
In meiotic cells, the pachytene checkpoint or meiotic recombination checkpoint is a surveillance mechanism that monitors critical processes, such as recombination and chromosome synapsis, which are essential for proper distribution of chromosomes to the meiotic progeny. We report here that Sas2-mediated acetylation of histone H4 at lysine 16 (H4K16ac) modulates meiotic checkpoint activity in response to synaptonemal complex defects. Our results reveal that proper levels of H4K16ac orchestrate this meiotic quality control mechanism and that Sir2 impinges on additional targets to fully activate the checkpoint.
The transcription factors ADR1 or CAT8 are required for RTG pathway activation and evasion from yeast acetic acid-induced programmed cell death in raffinose
December 2, 2016
Yeast Saccharomyces cerevisiae grown on glucose undergoes programmed cell death (PCD) induced by acetic acid (AA-PCD), but evades PCD when grown in raffinose. This is due to concomitant relief of carbon catabolite repression (CCR) and activation of mitochondrial retrograde signaling. In this work, we investigated the relationships between the RTG and CCR pathways in the modulation of AA-PCD sensitivity under glucose repression or de-repression conditions. Our data show that simultaneous mitochondrial retrograde pathway activation and SNF1-dependent relief of CCR have a key role in central carbon metabolism reprogramming which modulates the yeast acetic acid-stress response.
The ubiquitin-conjugating enzyme, Ubc1, indirectly regulates SNF1 kinase activity via Forkhead-dependent transcription
November 5, 2016
The SNF1 kinase class of serine/threonine kinases, which includes the AMP-dependent protein kinase (AMPK) in other systems, are of widespread interest because of their important roles in glucose homeostasis, stress resistance, and aging. Our goal was to identify discrete ubiquitin-conjugating enzymes that are involved in SNF1 kinase activity in response to glucose levels and anticipated revealing those which are involved in Snf1-Ub attachment. Here, we report that the cell cycle and stress-related E2, Ubc1, indirectly affects SNF1 kinase activity not through stability, but through upstream events.
Phylogenetic profiles of all membrane transport proteins of the malaria parasite highlight new drug targets
August 30, 2016
In order to combat the on-going malaria epidemic, discovery of new drug targets remains vital. Proteins that are essential to survival and specific to malaria parasites are key candidates. Here, we present a comprehensive orthology assignment of all Plasmodium falciparum putative membrane transport proteins and provide a detailed overview of the associated essential gene functions obtained through experimental genetics studies in human and murine model parasites.