Phosphatidylthreonine and Lipid-Mediated Control of Parasite Virulence

Arroyo-Olarte, Ruben D.; Brouwers, Jos F.; Kuchipudi, Arunakar; Helms, J. Bernd; Biswas, Aindrila; Dunay, Ildikò Rita; Lucius, Richard; Gupta, Nishith

doi:10.1371/journal.pbio.1002288

Cited by 50 publications

(91 citation statements)

References 48 publications

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“…Neutral lipids were analyzed by reverse phase HPLC‐tandem mass spectroscopy on a Sciex 4000 Q‐trap mass spectrometer (Sciex, Framingham, MA), equipped with an atmospheric pressure chemical ionization source. Intact phospholipids were analyzed by HILIC chromatography and mass spectrometry as described previously (Arroyo‐Olarte et al, ). Levels of detected lipids in ACM were normalized to total protein content.…”

Section: Methodsmentioning

confidence: 99%

Astrocyte lipid metabolism is critical for synapse development and function in vivo

Deijk

Camargo

Timmerman

et al. 2017

Glia

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150

114

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The brain is considered to be autonomous in lipid synthesis with astrocytes producing lipids far more efficiently than neurons. Accordingly, it is generally assumed that astrocyte-derived lipids are taken up by neurons to support synapse formation and function. Initial confirmation of this assumption has been obtained in cell cultures, but whether astrocyte-derived lipids support synapses in vivo is not known. Here, we address this issue and determined the role of astrocyte lipid metabolism in hippocampal synapse formation and function in vivo. Hippocampal protein expression for the sterol regulatory element-binding protein (SREBP) and its target gene fatty acid synthase (Fasn) was found in astrocytes but not in neurons. Diminishing SREBP activity in astrocytes using mice in which the SREBP cleavage-activating protein (SCAP) was deleted from GFAP-expressing cells resulted in decreased cholesterol and phospholipid secretion by astrocytes. Interestingly, SCAP mutant mice showed more immature synapses, lower presynaptic protein SNAP-25 levels as well as reduced numbers of synaptic vesicles, indicating impaired development of the presynaptic terminal. Accordingly, hippocampal short-term and long-term synaptic plasticity were defective in mutant mice. These findings establish a critical role for astrocyte lipid metabolism in presynaptic terminal development and function in vivo. GLIA 2017;65:670-682.

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Section: Methodsmentioning

confidence: 99%

Astrocyte lipid metabolism is critical for synapse development and function in vivo

Deijk

Camargo

Timmerman

et al. 2017

Glia

Self Cite

150

114

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“…To find the exact localization of TgATPase P -GC protein, the IMC was separated from the PM by treating extracellular parasites with α-toxin from Clostridium septicum (20 nM, 2 h) (List Biological Laboratories, US) followed by fixation on BSAcoated coverslips. In both cases, the standard secondary antibody staining procedure was performed afterwards, as described for immunofluorescence assay Lytic cycle assays--All assays were set up with fresh syringed-released parasites, essentially the same as reported earlier (Arroyo-Olarte et al 2015). Parasitized cultures (MOI: 2; 40-44 h post-infection) were washed with standard culture medium, scraped, and extruded through a 27G syringe (2x).…”

Section: Methodsmentioning

confidence: 99%

An unusual and physiologically vital protein with guanylate cyclase and P-type ATPase like domain in a pathogenic protist

Günay-Esiyok

Scheib

Noll

et al. 2018

Preprint

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Cyclic GMP is considered as one of the master regulators of diverse functions in eukaryotes; its architecture and functioning in protozoans remain poorly understood however. We characterized an unusual and extra-large guanylate cyclase (477-kDa) containing at least 4 putative P-type ATPase motifs and 21 transmembrane helices in a common parasitic protist, Toxoplasma gondii. This protein, termed as TgATPase P -GC due to its anticipated multi-functionality, localizes in the plasma membrane at the apical pole, while the corresponding cGMP-dependent protein kinase (TgPKG) is distributed in cytomembranes. Both proteins are expressed constitutively during the entire lytic cycle of the parasite in human cells, which suggests a post-translational control of cGMP signaling. Homology modeling indicated an activation of guanylate cyclase by heterodimerization of its two cyclase domains. TgATPase P -GC is refractory to genetic deletion, and its CRISPR/Cas9-mediated disruption aborts the lytic cycle. Likewise, Cre/loxP-regulated knockdown of the TgATPase P -GC by 3' UTR excision inhibited the parasite growth due to impairments in motility-dependent egress and invasion events. Consistently, cGMP-specific phosphodiesterase inhibitors restored the gliding motility of the mutant. A genetic repression of TgPKG, or its pharmacological inhibition phenocopied the defects observed in the TgATPase P -GC mutant. Our data show a vital function of cGMP signaling, which is inducted by an alveolate-specific guanylate cyclase coupled to P-type like ATPase, and transduced by a dedicated PKG in T. gondii. The presence of TgATPase P -GC orthologs in many other alveolates with contrasting habitats implies a divergent functional repurposing of cGMP signaling in protozoans. The work also lays an avenue to systematically dissect the cascade and understand its evolution in a model protist.

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“…Despite their levels being reduced in TgGC-depleted cells, the fatty acid profile of PA, PS and PI was broadly similar, although PA and PS showed slight decreases in oleic acid 18:1, and slight concomitant increases in unsaturated C16:0 and C18:0 ( Figure 2C). In TgGC-depleted cells PT showed an overall normal FA profile but with slightly increased levels of the signature 20:1 and 20:4 FA chains for which PT is known ( Figure 2C) (Arroyo-Olarte et al 2015). Interestingly, the FA profile of PC showed a large increase in 18:1 suggesting that the TgGC-depleted cells are either synthesising or scavenging more of this specific PC (Figure 2C).…”

Section: Tggc-depleted Parasites Display Both Disrupted Phospholipid mentioning

confidence: 95%

Rapid kinetics of lipid second messengers controlled by a cGMP signalling network coordinates apical complex functions inToxoplasmatachyzoites

Katris

Yamaryo‐Botté

Janouškovec

et al. 2020

Preprint

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Host cell invasion and subsequent egress by Toxoplasma parasites is regulated by a network of cGMP, cAMP, and calcium signalling proteins. Such eukaryotic signalling networks typically involve lipid second messengers including phosphatidylinositol phosphates (PIPs), diacylglycerol (DAG) and phosphatidic acid (PA). However, the lipid signalling network in Toxoplasma is poorly defined. Here we present lipidomic analysis of a mutant of central flippase/guanylate cyclase TgGC in Toxoplasma, which we show has disrupted turnover of signalling lipids impacting phospholipid metabolism and membrane stability. The turnover of signalling lipids is extremely rapid in extracellular parasites and we track changes in PA and DAG to within 5 seconds, which are variably defective upon disruption of TgGC and other signalling proteins. We then identify the position of each protein in the signal chain relative to the central cGMP signalling protein TgGC and map the lipid signal network coordinating conoid extrusion and microneme secretion for egress and invasion.

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Phosphatidylthreonine and Lipid-Mediated Control of Parasite Virulence

Cited by 50 publications

References 48 publications

Astrocyte lipid metabolism is critical for synapse development and function in vivo

Astrocyte lipid metabolism is critical for synapse development and function in vivo

An unusual and physiologically vital protein with guanylate cyclase and P-type ATPase like domain in a pathogenic protist

Rapid kinetics of lipid second messengers controlled by a cGMP signalling network coordinates apical complex functions inToxoplasmatachyzoites

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