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.
Differentiated cytoplasmic granule formation in quiescent and non-quiescent cells upon chronological aging
March 3, 2016
Stationary phase cultures represent a complicated cell population comprising at least two different cell types, quiescent (Q) and non-quiescent (NQ) cells. The authors show that the cell fate of NQ cells is largely irreversible even if they are allowed to reenter mitosis. Their results reveal that the formation of different granule structures may represent the early stage of cell type differentiation in yeast stationary phase cultures.
Towards understanding the gliotoxin detoxification mechanism: in vivo thiomethylation protects yeast from gliotoxin cytotoxicity
February 19, 2016
Gliotoxin is a mycotoxin produced by some species of ascomycete fungi including the opportunistic human pathogen Aspergillus fumigatus. In order to produce gliotoxin the host organism needs to have evolved a self-protection mechanism. The authors demonstrate that the activity of a novel thiomethyltransferase is requiered for protection against exogenous gliotoxin and provide implications for understanding the evolution of gliotoxin self-protection mechanisms.
Mitochondrial proteomics of the acetic acid – induced programmed cell death response in a highly tolerant Zygosaccharomyces bailii – derived hybrid strain
January 22, 2016
Very high concentrations of acetic acid at low pH induce programmed cell death (PCD) in both the experimental model Saccharomyces cerevisiae and in Zygosaccharomyces bailii, the latter being considered the most problematic acidic food spoilage yeast due to its remarkable intrinsic resistance to this food preservative. This study offers insights into the mechanisms involved in acetic acid - induced PCD in the Z. bailii-derived hybrid strain ISA1307 by analyzing the yeast mitochondrial protein expression profile of cells challenged by acetic acid.
The transcriptional repressor Sum1p counteracts Sir2p in regulation of the actin cytoskeleton, mitochondrial quality control and replicative lifespan in Saccharomyces cerevisiae
January 18, 2016
Increasing the stability or dynamics of the actin cytoskeleton can extend lifespan in C. elegans and S. cerevisiae. Actin cables of budding yeast, bundles of actin filaments that mediate cargo transport, affect lifespan control through effects on mitochondrial quality control. Here, we report that Sum1p and Sir2p inversely regulate actin and mitochondrial maintenance, as well as lifespan.
Inhibition of Aβ42 oligomerization in yeast by a PICALM ortholog and certain FDA approved drugs
January 18, 2016
The formation of small Aβ42 oligomers has been implicated as a toxic species in Alzheimer disease (AD). Here, we show that the mechanism of the PICALM, human AD risk factor, is likely to reduce the level of Aβ42 oligomers in cells. We screened FDA-approved drugs to identify candidates that prevent the formation of Aβ42 small oligomers using the yeast Aβ42-RF reporter system. We also showed that each of the drug hits counteract yeast and mammalian cell toxicity associated with Aβ42 small aggregates.
Global translational impacts of the loss of the tRNA modification t6A in yeast
December 18, 2015
The universal tRNA modification t6A is found at position 37 of nearly all tRNAs decoding ANN codons. Analysis of codon occupancy rates suggests that one of the major roles of t6A is to homogenize the process of elongation by slowing the elongation rate at codons decoded by high abundance tRNAs and I34:C3 pairs while increasing the elongation rate of rare tRNAs and G34:U3 pairs. This work reveals that the consequences of t6A absence are complex and multilayered and has set the stage to elucidate the molecular basis of the observed phenotypes.
Ergosterone-coupled Triazol molecules trigger mitochondrial dysfunction, oxidative stress, and acidocalcisomal Ca2+ release in Leishmania mexicana promastigotes
December 11, 2015
The protozoan parasite Leishmania causes a variety of sicknesses with different clinical manifestations known as leishmaniasis. Investigations looking for new targets or new active molecules focus mainly on the disruption of parasite specific pathways. In this sense, ergosterol biosynthesis is one of the most attractive because it does not occur in mammals. Our results indicate that ergosterone-triazol coupled molecules induce a regulated cell death process in the parasite and may represent starting point molecules in the search of new chemotherapeutic agents to combat leishmaniasis.
INO1 transcriptional memory leads to DNA zip code-dependent interchromosomal clustering
November 13, 2015
Many genes localize at the nuclear periphery through physical interaction with the nuclear pore complex (NPC). We have found that the yeast INO1 gene is targeted to the NPC both upon activation and for several generations after repression, a phenomenon called epigenetic transcriptional memory. Targeting of INO1 to the NPC requires distinct cis-acting promoter DNA zip codes under activating conditions and under memory conditions. When at the nuclear periphery, active INO1 clusters with itself and with other genes that share the GRS I zip code. Here, we show that during memory, the two alleles of INO1 cluster in diploids and endogenous INO1 clusters with an ectopic INO1 in haploids. After repression, INO1 does not cluster with GRS I - containing genes. Furthermore, clustering during memory requires Nup100 and two sets of DNA zip codes...
A central role for TOR signalling in a yeast model for juvenile CLN3 disease
November 11, 2015
Yeasts provide an excellent genetically tractable eukaryotic system for investigating the function of genes in their biological context, and are especially relevant for those conserved genes that cause disease. Bond et al. study the role of btn1, the orthologue of a human gene that underlies an early onset neurodegenerative disease (juvenile CLN3 disease, neuronal ceroid lipofuscinosis (NCLs) or Batten disease) in the fission yeast Schizosaccharomyces pombe.