Research, Research Reports
Transcriptomic response to different heme sources in Trypanosoma cruzi epimastigotes
Evelyn Tevere1,a, María G. Mediavilla1,a, Cecilia B. Di Capua1, Marcelo L. Merli1, Carlos Robello2,3, Luisa Berná2,4 and Julia A. Cricco
This study uncovers how the Chagas disease parasite adapts to changes in heme, an essential molecule for its survival, providing transcriptional clues to heme metabolism and identifying a previously unreported heme-binding protein in T. cruzi.
Sir2 regulates selective autophagy in stationary-phase yeast cells
Ji-In Ryua, Juhye Junga, and Jeong-Yoon Kim
This study establishes Sir2 as a previously unrecognized regulator of selective autophagy during the stationary phase and highlight how cells dynamically control organelle degradation.
Luminal acetylation of microtubules is not essential for Plasmodium berghei and Toxoplasma gondii survival
Thrishla Kumar1,a, Katharina Röver2,a, Johannes F. Stortz3,a, Annika M. Binder2,a, Benjamin Spreng2, Madlen Konert2, Markus Meissner1, Friedrich Frischknecht2,4 and Elena Jimenez-Ruiz1,*
Acetylation of α-tubulin at lysine 40 is not essential for cytoskeletal stability in Plasmodium berghei or Toxoplasma gondii, suggesting redundancy and plasticity in microtubule regulation in these parasites.
The dual-site agonist for human M2 muscarinic receptors Iper-8-naphtalimide induces mitochondrial dysfunction in Saccharomyces cerevisiae
Angela Cirigliano1,a, Antonia Amelina2,a, Elena Passarini2, Alessandra Ricelli1, Nicole Balasco1, Mattia Mori3, Bruno Botta4, Maria Egle De Stefano2,5, Claudio Papotto6, Claudia Guerriero2, Ada Maria Tata2,5 and Teresa Rinaldi2,*
S. cerevisiae is a model to study human GPCRs. N-8-Iper, active against glioblastoma via M2 receptor, causes mitochondrial damage in yeast by binding Ste2, highlighting evolutionary conservation of GPCRs.
The core genetic drivers of chronological aging in yeast are universal regulators of longevity
Erika Cruz-Bonilla1, Sergio E. Campos2, Soledad Funes3, Cei Abreu-Goodger4 and Alexander DeLuna1,2,*
This study provides an integrated view of the core genetic landscape underlying aging in yeast, highlighting the value of the chronological lifespan paradigm for investigating conserved mechanisms of aging.
Organelle activity organized by the endoplasmic reticulum-mitochondria encounter structure –ERMES– is essential for Podospora anserina development
Melisa Álvarez-Sánchez1, Matías Ramírez-Noguez1, Beatriz Aguirre-López1 and Leonardo Peraza-Reyes1
This study shows that the regulation of the activity of multiple organelles by the ERMES (Endoplasmic Reticulum-Mitochondria Encounter Structure) tethering complex is essential for fungal growth and sexual development.
Role of the putative sit1 gene in normal germination of spores and virulence of the Mucor lusitanicus
Bernadett Vágó1,2, Kitti Bauer1,2, Naomi Varghese1,2, Sándor Kiss-Vetráb1,2, Sándor Kocsubé1,2, Mónika Varga1,2, András Szekeres1,2, Csaba Vágvölgyi1,2, Tamás Papp1,2,3,# and Gábor Nagy1,2,3,#
Mucormycosis is a life-threatening infection caused by certain members of the fungal order Mucorales, with increased incidence in recent years. Individuals with untreated diabetes mellitus, and patients treated with deferoxamine are particularly susceptible to this infection.
Tumor microenvironment signatures enhances lung adenocarcinoma prognosis prediction: Implication of intratumoral microbiota
Fei Zhao1,#, Lei Wang2,3,4,#, Dongjie Du5, Heaven Zhao6,7, Geng Tian6,7, Yufeng Li2,3,8, Yankun Liu2,8,9, Zhiwu Wang2,3,10, Dasheng Liu11, Jingwu Li2,3,12, Lei Ji6,7 and Hong Zhao1
The interaction between intratumoral microbiome and the tumor microenvironment (TME) has furthered our understanding of tumor ecology. Yet, the implications of their interaction for lung cancer management remain unclear.
Persistence phenotype of adherent-invasive Escherichia coli in response to ciprofloxacin, revealing high-persistence strains
Valeria Pérez-Villalobos1, Roberto Vidal2, Marcela A. Hermoso3,4 and Paula Bustamante1
We investigated the roles of the resident antibiotic resistance plasmid, the stress response protein HtrA, and macrophage-induced persister formation. Our results revealed broad variability in persister cell formation among AIEC strains.
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.
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.