Research, Research Reports

Tracking autophagy during proliferation and differentiation of Trypanosoma brucei

William R. Proto1, Nathaniel G. Jones1, Graham H. Coombs2, and Jeremy C. Mottram1

This article provides insights into the function of autophagy, a cellular degradation and recycling pathway, in the protozoan parasite Trypanosoma brucei.

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Microbial competition between Escherichia coli and Candida albicans reveals a soluble fungicidal factor

March 7, 2018

Localized and systemic fungal infections caused by Candida albicans can lead to significant mortality and morbidity. Here, Cabral et al. show that E. coli produces a soluble factor that kills C. albicans in a magnesium-dependent fashion such that depletion of available magnesium is essential for toxicity.

Impact of F1Fo-ATP-synthase dimer assembly factors on mitochondrial function and organismic aging

January 30, 2018

In aerobic organisms, mitochondrial F1Fo-ATP-synthase is the major site of ATP production. Here, Rampello et al. report on the role of the two dimer assembly factors PaATPE and PaATPG of the aging model Podospora anserina validating a model that links mitochondrial membrane remodeling to aging and identify specific molecular components triggering this process.

Yeast quiescence exit swiftness is influenced by cell volume and chronological age

December 6, 2017

Quiescence exit swiftness is crucial not only for micro-organisms in competition for an environmental niche, such as yeast, but also for the maintenance of tissue homeostasis in multicellular species. Here, Laporte et al. explore the effect of replicative and chronological age on Saccharomyces cerevisiae quiescence exit efficiency. Overall, their data illustrate that the quiescent state is a continuum evolving with time, early and deep quiescence being distinguishable by the cell’s proficiency to re-enter the proliferation cycle.

Mitochondrial energy metabolism is required for lifespan extension by the spastic paraplegia-associated protein spartin

November 30, 2017

This article indicates that spartin, a protein linked to hereditary spastic paraplegias, extends yeast lifespan and reduces age-related damage by associating with mitochondria and interacting with key metabolic proteins, implicating energy metabolism in its protective role during aging.

The neuroprotective steroid progesterone promotes mitochondrial uncoupling, reduces cytosolic calcium and augments stress resistance in yeast cells

May 31, 2017

Progesterone, known for its role in the reproductive system, also acts as a neurosteroid and has been suggested to aid recovery from traumatic brain injury; a study using yeast models shows that progesterone can protect against apoptosis, reduce oxidative stress and calcium spikes, and increase mitochondrial function, independent of traditional progesterone receptors or calcium transporters.

A simple microfluidic platform to study age-dependent protein abundance and localization changes in Saccharomyces cerevisiae

April 13, 2017

We have developed a user-friendly microfluidic system paired with a genetic approach to enrich and study ageing mother yeast cells, enabling the monitoring of protein abundance and localization changes during the crucial first half of their replicative lifespan, leading to the discovery of novel age-dependent protein behaviors.

The frequency of yeast [PSI+] prion formation is increased during chronological ageing

March 27, 2017

Aging is marked by a decline in cellular functions and the increased formation of the yeast [PSI+] prion, an altered translation termination factor, which suggests that autophagy suppresses age-related prion development. Interestingly, yeast cells that adopt the [PSI+] form exhibit better survival through aging, indicating that [PSI+] formation, linked to enhanced autophagy, may confer advantages such as reduced protein aggregation and improved cell viability.

A multigene family encoding surface glycoproteins in Trypanosoma congolense

March 2, 2017

Trypanosoma congolense, the causative agent of the most important livestock disease in Africa, expresses specific surface proteins involved in its parasitic lifestyle. By mining the T. congolense genome database, we identified a novel family of lectin-like glycoproteins (TcoClecs).

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.

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.