U.S. Department of Energy

Pacific Northwest National Laboratory

Metabolic reprogramming during purine stress in the protozoan pathogen Leishmania donovani.

TitleMetabolic reprogramming during purine stress in the protozoan pathogen Leishmania donovani.
Publication TypeJournal Article
Year of Publication2014
AuthorsMartin JL, Yates PA, Soysa R, Alfaro JF, Yang F, Burnum-Johnson KE, Petyuk VA, Weitz KK, Camp DG, Smith RD, Wilmarth PA, David LL, Ramasamy G, Myler PJ, Carter NS
JournalPLoS Pathog
Abstract

The ability of Leishmania to survive in their insect or mammalian host is dependent upon an ability to sense and adapt to changes in the microenvironment. However, little is known about the molecular mechanisms underlying the parasite response to environmental changes, such as nutrient availability. To elucidate nutrient stress response pathways in Leishmania donovani, we have used purine starvation as the paradigm. The salvage of purines from the host milieu is obligatory for parasite replication; nevertheless, purine-starved parasites can persist in culture without supplementary purine for over three months, indicating that the response to purine starvation is robust and engenders parasite survival under conditions of extreme scarcity. To understand metabolic reprogramming during purine starvation we have employed global approaches. Whole proteome comparisons between purine-starved and purine-replete parasites over a 6-48 h span have revealed a temporal and coordinated response to purine starvation. Purine transporters and enzymes involved in acquisition at the cell surface are upregulated within a few hours of purine removal from the media, while other key purine salvage components are upregulated later in the time-course and more modestly. After 48 h, the proteome of purine-starved parasites is extensively remodeled and adaptations to purine stress appear tailored to deal with both purine deprivation and general stress. To probe the molecular mechanisms affecting proteome remodeling in response to purine starvation, comparative RNA-seq analyses, qRT-PCR, and luciferase reporter assays were performed on purine-starved versus purine-replete parasites. While the regulation of a minority of proteins tracked with changes at the mRNA level, for many regulated proteins it appears that proteome remodeling during purine stress occurs primarily via translational and/or post-translational mechanisms.

DOI10.1371/journal.ppat.1003938
Alternate JournalPLoS Pathog.
PubMed ID24586154
PubMed Central IDPMC3937319
Grant List5P41 RR018522-10 / RR / NCRR NIH HHS / United States
8P41 GM103493-10 / GM / NIGMS NIH HHS / United States
AI023682 / AI / NIAID NIH HHS / United States
AI044138 / AI / NIAID NIH HHS / United States
NS065405 / NS / NINDS NIH HHS / United States
P30CA069533 / CA / NCI NIH HHS / United States
P30EY010572 / EY / NEI NIH HHS / United States
T32 AI007472 / AI / NIAID NIH HHS / United States
T32 GM071338-06 / GM / NIGMS NIH HHS / United States
UL1TR000128 / TR / NCATS NIH HHS / United States
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