Vol. 04, 2017
S. pombe placed on the prion map
Jacqueline Hayles
This article comments on work published by Sideri et al. (Microbial Cell, 2017), which identified the Ctr4 prion in S. pombe.
Balanced CoQ6 biosynthesis is required for lifespan and mitophagy in yeast
Isabel González-Mariscal, Aléjandro Martín-Montalvo, Cristina Ojeda-González, Adolfo Rodríguez-Eguren, Purificación Gutiérrez-Ríos, Plácido Navas, and Carlos Santos-Ocaña
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.
Breaking the bilayer: OMV formation during environmental transitions
Katherine E. Bonnington, Meta J. Kuehn
This article comments on work published by Bonnington & Kuehn (MBio, 2016), which shows how gram-negative bacteria maintain the barrier properties of the outer membrane (OM) in a wide array of physiological conditions despite their inability to degrade lipopolysaccharide (LPS) and protein material present in the outer leaflet of the OM.
Mutational analysis of fructose-1,6-bis-phosphatase FBP1 indicates partially independent functions in gluconeogenesis and sensitivity to genotoxic stress
Ali Ghanem, Ana Kitanovic, Jinda Holzwarth, Stefan Wölfl
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 tug-of-war over MTOR in Legionella infections
Stanimir S. Ivanov
This article comments on work published by Abshire et al (PLoS Pathog, 2016), which uncovered that the host metabolic checkpoint kinase Mechanistic target of rapamycin (MTOR) is a central regulator of the pathogen niche expansion program.
A new role for Holliday junction resolvase Yen1 in processing DNA replication intermediates exposes Dna2 as an accessory replicative helicase
Benoît Falquet1,2 and Ulrich Rass
This article comments on work published by Ölmezer et al. (Nat Commun, 2016), which revealed a new function of Yen1, distinct from its previously known role as a Holliday junction resolvase, mediating the removal of branched HR intermediates.
The copper transport-associated protein Ctr4 can form prion-like epigenetic determinants in Schizosaccharomyces pombe
Theodora Sideri1, Yoko Yashiroda2, David A. Ellis1, María Rodríguez-López1, Minoru Yoshida2, Mick F. Tuite3 & Jürg Bähler1
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.
Using microbes as a key tool to unravel the mechanism of autophagy and the functions of the ATG proteins
Mario Mauthe1,2 and Fulvio Reggiori1,2
Microbes have served to discover and characterize unconventional functions of the ATG proteins, which are uncoupled from their role in autophagy. In our recent study, we have taken advantage of viruses as a screening tool to determine the extent of the unconventional functions of the ATG proteome and characterize one of them.
A new role for the nuclear basket network
Paola Gallardo1, Silvia Salas-Pino1 and Rafael R. Daga1
This article comments on work published by Salas-Pino et al. (J Cell Biol, 2017), which describes a novel function of the fission yeast nuclear basket component - the translocated promoter region (TPR) nucleoporin Alm1 - in proper localization of the proteasome to the nuclear envelope.
A genome-wide screen for FTY720-sensitive mutants reveals genes required for ROS homeostasis
Kanako Hagihara1, Kanako Kinoshita1, Kouki Ishida1, Shihomi Hojo1, Yoshinori Kameoka1, Ryosuke Satoh1, Teruaki Takasaki1 and Reiko Sugiura1
Fingolimod hydrochloride (FTY720) is an immune modulator for multiple sclerosis that also induces cancer cell apoptosis through reactive oxygen species generation, with a new study using fission yeast uncovering a gene network related to ROS homeostasis as a possible mechanism of FTY720's toxicity.
VAMP8 mucin exocytosis attenuates intestinal pathogenesis by Entamoeba histolytica
Steve Cornick1, France Moreau1, Herbert Y. Gaisano2, Kris Chadee1
This article comments on work published by Cornick et al. (mBio, 2017), which nominates SNARE-mediated exocytosis as the putative mechanism responsible for pathogen-induced mucus secretion from goblet cells.
Aminoglycoside resistance profile and structural architecture of the aminoglycoside acetyltransferase AAC(6’)-Im
Clyde A. Smith1, Monolekha Bhattacharya2, Marta Toth2, Nichole K. Stewart2 and Sergei B. Vakulenko2
AAC(6')-Im, a monofunctional acetyltransferase, imparts increased resistance to certain aminoglycosides compared to its bifunctional homolog AAC(6')-Ie, with structural studies revealing differences in substrate binding that explain the discrepancies in their enzymatic activity and resistance profiles.
Shutdown of interferon signaling by a viral-hijacked E3 ubiquitin ligase
Kaitlin A. Davis1 and John T. Patton2
This article comments on work published by Davis et al. (mBio, 2017), which describes molecular requirements that govern NSP1 recognition of β-TrCP, including an essential degron phosphorylation event, and the step-wise incorporation of NSP1 into hijacked cullin-RING E3 ligases (CRLs) that ubiquitinate and tag β-TrCP for degradation.
The tug-of-war over MTOR in Legionella infections
Stanimir S. Ivanov
This article comments on work published by Abshire et al (PLoS Pathog, 2016), which uncovered that the host metabolic checkpoint kinase Mechanistic target of rapamycin (MTOR) is a central regulator of the pathogen niche expansion program.
A new role for Holliday junction resolvase Yen1 in processing DNA replication intermediates exposes Dna2 as an accessory replicative helicase
Benoît Falquet1,2 and Ulrich Rass
This article comments on work published by Ölmezer et al. (Nat Commun, 2016), which revealed a new function of Yen1, distinct from its previously known role as a Holliday junction resolvase, mediating the removal of branched HR intermediates.
Toxin-mediated gene regulatory mechanism in Staphylococcus aureus
Hwang-Soo Joo and Michael Otto
This article comments on work published by Joo et al. (MBio, 2016), which describes the first molecular regulatory mechanism exerted by an S. aureus toxin, setting a paradigmatic example of how S. aureus toxins may influence cell functions to adjust them to times of toxin production.
Uncovering the hidden: complexity and strategies for diagnosing latent tuberculosis
Mario Alberto Flores-Valdez
This editorial postulates that advanced proteomic and transcriptomic techniques are evolving and may enhance the detection of latent tuberculosis, thereby distinguishing true M. tuberculosis infections from other conditions, which is vital for controlling potential reactivation and transmission.
The Yin & Yang of Mitochondrial Architecture – Interplay of MICOS and F1Fo-ATP synthase in cristae formation
Heike Rampelt1 and Martin van der Laan2
This Editorial posits that mitochondrial cristae architecture is shaped by the interplay of MICOS and ATP synthase, with a recent study illuminating their roles in cristae formation and maintenance.
When a ribosomal protein grows up – the ribosome assembly path of Rps3
Brigitte Pertschy
This article comments on two papers by Mitterer et al., which followed yeast protein Rps3, highlighting the sophisticated mechanisms for protein protection, nuclear transport, and integration into pre-ribosomal particles for final assembly with 40S subunits.
Staphylococcus aureus type I signal peptidase: essential or not essential, that’s the question
Wouter L.W. Hazenbos1, Elizabeth Skippington2 and Man-Wah Tan1
This article comments on work published by Morisaki et al. (mBio, 2016), which characterized a novel ABC transporter. This transporter apparently compensates for SpsB’s essential function by mediating alternative cleavage of a subset of proteins at a site distinct from the SpsB-cleavage site, leading to SpsB-independent secretion.
Transceptors as a functional link of transporters and receptors
George Diallinas
A relative newcomer in environment sensing are the so called transceptors, membrane proteins that possess both solute transport and receptor-like signaling activities. Now, the transceptor concept is further enlarged to include micronutrient sensing via the iron and zinc high-affinity transporters of Saccharomyces cerevisiae.
S. pombe placed on the prion map
Jacqueline Hayles
This article comments on work published by Sideri et al. (Microbial Cell, 2017), which identified the Ctr4 prion in S. pombe.
Using microbes as a key tool to unravel the mechanism of autophagy and the functions of the ATG proteins
Mario Mauthe1,2 and Fulvio Reggiori1,2
Microbes have served to discover and characterize unconventional functions of the ATG proteins, which are uncoupled from their role in autophagy. In our recent study, we have taken advantage of viruses as a screening tool to determine the extent of the unconventional functions of the ATG proteome and characterize one of them.
The tug-of-war over MTOR in Legionella infections
January 30, 2017
This article comments on work published by Abshire et al (PLoS Pathog, 2016), which uncovered that the host metabolic checkpoint kinase Mechanistic target of rapamycin (MTOR) is a central regulator of the pathogen niche expansion program.
A new role for Holliday junction resolvase Yen1 in processing DNA replication intermediates exposes Dna2 as an accessory replicative helicase
January 2, 2017
This article comments on work published by Ölmezer et al. (Nat Commun, 2016), which revealed a new function of Yen1, distinct from its previously known role as a Holliday junction resolvase, mediating the removal of branched HR intermediates.
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.
Using microbes as a key tool to unravel the mechanism of autophagy and the functions of the ATG proteins
December 30, 2016
Microbes have served to discover and characterize unconventional functions of the ATG proteins, which are uncoupled from their role in autophagy. In our recent study, we have taken advantage of viruses as a screening tool to determine the extent of the unconventional functions of the ATG proteome and characterize one of them.
Toxin-mediated gene regulatory mechanism in Staphylococcus aureus
December 29, 2016
This article comments on work published by Joo et al. (MBio, 2016), which describes the first molecular regulatory mechanism exerted by an S. aureus toxin, setting a paradigmatic example of how S. aureus toxins may influence cell functions to adjust them to times of toxin production.
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.
Transceptors as a functional link of transporters and receptors
George Diallinas
A relative newcomer in environment sensing are the so called transceptors, membrane proteins that possess both solute transport and receptor-like signaling activities. Now, the transceptor concept is further enlarged to include micronutrient sensing via the iron and zinc high-affinity transporters of Saccharomyces cerevisiae.