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.
VDAC regulates AAC-mediated apoptosis and cytochrome c release in yeast
August 25, 2016
Mitochondrial outer membrane permeabilization is a key event in apoptosis processes leading to the release of lethal factors. In this study, we sought to determine whether Por1p functionally interacts with ADP/ATP carrier (AAC) proteins, as well as its contribution to cytochrome c release and yeast apoptosis induced by acetic acid treatment. Our data indicate that Por1p may regulate cell survival by acting as a negative regulator of AAC proteins in the apoptotic cascade.
Attenuation of polyglutamine-induced toxicity by enhancement of mitochondrial OXPHOS in yeast and fly models of aging
July 26, 2016
Defects in mitochondrial biogenesis and function are common in many neurodegenerative disorders, including Huntington’s disease (HD). We could shown that enhancement of mitochondrial biogenesis protects against neurodegeneration in HD yeast and fly models. Our results suggest that therapeutic interventions aiming at the enhancement of mitochondrial respiration and OXPHOS could reduce polyQ toxicity and delay disease onset.
Cox1 mutation abrogates need for Cox23 in cytochrome c oxidase biogenesis
June 30, 2016
Cox23 is a known conserved assembly factor for cytochrome c oxidase, although its role in cytochrome c oxidase (CcO) biogenesis remains unresolved. To gain additional insights into its role, we isolated spontaneous suppressors of the respiratory growth defect in cox23∆ yeast cells. In this report, we describe the isolation of a robust suppressor of the respiratory defect in cox23∆ cells that mapped to the mitochondrial-encoded Cox1 subunit.
Increased spontaneous recombination in RNase H2-deficient cells arises from multiple contiguous rNMPs and not from single rNMP residues incorporated by DNA polymerase epsilon
May 15, 2016
Ribonucleotides (rNMPs) can become embedded in DNA from insertion by DNA polymerases, failure to remove Okazaki fragment primers, R-loops that can prime replication, and RNA/cDNA-mediated recombination. We report here that recombination is not stimulated by rNMPs incorporated by the replicative polymerase epsilon. Instead, recombination seems to be stimulated by multiple contiguous rNMPs, which may arise from R-loops or replication priming events.
Construction and evaluation of yeast expression networks by database-guided predictions
May 10, 2016
DNA-Microarrays are powerful tools to obtain expression data on the genome-wide scale. We set out to define a way to cluster microarray data according to their expressional relationship and to obtain information on the significance of this clustering approach.
Optogenetic monitoring identifies phosphatidylthreonine-regulated calcium homeostasis in Toxoplasma gondii
May 1, 2016
Toxoplasma gondii is an obligate intracellular parasite, which inflicts acute as well as chronic infections in a wide range of warm-blooded vertebrates. Using an optogenetic sensor to monitor subcellular calcium in this model intracellular pathogen we found a novel regulatory function of phosphatidylthreonine in calcium signaling.
Filamentation protects Candida albicans from amphotericin B-induced programmed cell death via a mechanism involving the yeast metacaspase, MCA1
April 25, 2016
Candida albicans proliferates in two distinct cell types: blastopores and filaments. Programmed cell death is a controlled form of cell suicide that occurs when C. albicans cells are exposed to fungicidal drugs like amphotericin B and caspofungin, and to other stressful conditions. We provide evidence that programmed cell death is cell-type specific in yeast: Filamentous C. albicans cells are more resistant to amphotericin B- and caspofungin-induced programmed cell death than their blastospore counterparts. Our genetic data suggest that this phenomenon is mediated by a protective mechanism involving the yeast metacaspase, MCA1.
Formaldehyde fixation is detrimental to actin cables in glucose-depleted S. cerevisiae cells
April 13, 2016
Actin filaments form cortical patches and emanating cables in fermenting cells of Saccharomyces cerevisiae. We assume that stability of actin cables reflects the metabolic status of the cell. Based on comparison of live and formaldehyde-fixed cells, our data suggest that formaldehyde affects respiration before fixation and this uneven signaling results in destabilization of actin cables in glucose-deprived cells.
Insights into dynamin-associated disorders through analysis of equivalent mutations in the yeast dynamin Vps1
March 22, 2016
The dynamins represent a superfamily of proteins that have been shown to function in a wide range of membrane fusion and fission events. An increasing number of mutations in the human classical dynamins, Dyn-1 and Dyn-2 has been reported, with diseases caused by these changes ranging from Charcot-Marie-Tooth disorder to epileptic encephalopathies. This study aimed to use the dynamin-like protein Vps1 of Saccharomyces cerevisiae as a model to gain insights into the mechanistic defects caused by specific dynamin mutations considered to underlie a number of diseases.
Genomic saturation mutagenesis and polygenic analysis identify novel yeast genes affecting ethyl acetate production, a non-selectable polygenic trait
March 18, 2016
Isolation of mutants in populations of microorganisms has been a valuable tool in experimental genetics for decades. The main disadvantage, however, is the inability of isolating mutants in non-selectable polygenic traits. Our study shows that genomic saturation mutagenesis combined with complex trait polygenic analysis could be used successfully to identify causative alleles underlying many non-selectable, polygenic traits in small collections of haploid strains with multiple induced mutations.