Comparison of cultured and sand fly-derived promastigotes by means of RNA-Seq
Ontology highlight
ABSTRACT:
ORGANISM(S): Leishmania infantum
PROVIDER: GSE102668 | GEO | 2018/08/15
REPOSITORIES: GEO
Similar Datasets
Project description:Leishmania infantum (Kinetoplastida:Trypanosomatidae) is the etiological agent of zoonotic visceral leishmaniasis in the Mediterranean basin. The motile promastigote stage infects the hematophagous sand fly vector host and amastigotes survives and multiplies within phagocytes of the mammalian host. Promastigotes are routinely cultured in liquid undefined media and are considered to mimic the environment within the sand fly gut. We have put this to the test by high-throughput gene expression profiling by shotgun DNA microarrays generated in our laboratory. This has been possible thanks to RNA amplification.
2016-05-05 | GSE70992 | GEO
Project description:Leishmania infantum is the causative agent of zoonotic visceral leishmaniasis in Mediterranean areas and also acts as an opportunistic parasite in HIV patients. Metacyclic promastigotes are transmitted during bloodmeals of the sand-fly host after development. Metacyclogenesis can be micmiked in axenic cultures and peanut lectin (PNA) agglutination followed by two-step centrifugation allows the separation of procyclic and metacyclic promastigotes in L. major. The purpose of this study is to isolate both fractions simultaneously from the same population of L. infantum in stationary phase of axenic culture and compare their expression profiles through DNA microarrays, specially focusing on metacyclic promastigotes. Whole-genome shotgun DNA microarrays were constructed and used to analyse the stationary-phase procyclic and metacyclic expression profiles. Four biological replicates of the experiment were performed and analysed, so that 322 clones with meaningful values of stage-specific regulation were selected. We found several genes dealing with primary metabolism, differentiation in procyclic promastigotes and with development of infectivity in metacyclic promastigotes. The differences we have found between the procyclic (PNA+) and metacyclic (PNA-) transcriptomes demonstrate that negative selection of metacyclic promastigotes through PNA agglutination is suitable in L. infantum and both fractions can be isolated. In addition, up-regulation of genes implied in lipophosphoglycan (LPG), proteophosphoglycan (PPG) and glycoprotein biosynthesis indicate that metacyclic promastigotes are related with infectivity. Keywords: comparative hybridization between cDNAs from procyclic PNA+ and metacyclic PNA- promastigotes of L.infantum
2009-05-14 | GSE11269 | GEO
Project description:Leishmania chagasi is the causative agent of zoonotic visceral leishmaniasis in Brazil, being domestic and stray dogs the main reservoirs. The development of the parasite involves two stages. The promastigote is extracellular and develops within the sand fly gut. The amastigote survives inside the harsh environment of the phagolysosome of mammalian host phagocytes, where pH is acidic, temperature higher than in the sand fly vector and hydrolytic enzymes act. In addition, the host phagocyte displays the nitric oxide defense mechanism against the amastigote. Promastigotes are also able to withstand NO even when they develop within the sand fly gut. This can be explained with the pre-adaptative hypothesis, which has been supported by us and others elsewhere and consists of preparation of promastigotes in advance for development towards the amastigote stage. For this reason, the comparison of NO-resistant and sensitive promastigotes is valuable. The two-dimension electrophoresis-mass spectrometry (2DE-MS/MS) approach has been performed to study differential protein abundance comparing L. chagasi NO-sensitive and resistant promastigotes. This analysis has revealed differential expression of genes directly and indirectly involved in NO-resistance, highlighting up-regulation of the glucose-6-phosphate dehydrogenase (G6PD) in NO-resistant promastigotes and down-regulation of the glutathione peroxidase (GPX) and the arginase (ARG) in NO-sensitive ones. These data are a starting point in the search of vaccine candidates and/or drug targets.
2016-03-31 | PXD002939 | Pride
Project description:The DEAD/H RNA helicase LINF_220021200 (DEVH1) gene from Leishmania infantum (Kinetoplastida:Trypanosomatidae) was cloned in the pTEX expression plasmid vector for trypanosomatids. Leishmania infantunm promastigotes were transfected and a knock-in L. infantum promastigote cell line was selected with geneticin (G418). A pTEX control promastigote line was also generated. Then, three independent biological replicate cultures of each pTEX-DEVH1 and pTEX promastigote lines were performed in the presence of the selective agent. The parasites were harvested on day 7 (stationary phase). Total mRNA samples were obtained. Cyanine dye-labelled samples were obtained from the knock-in and the control line (Cy5 and Cy3, respectively) and they were hybridized with custom whole-genome L. infantum DNA microarrays. This platform is included in GEO (GPL6781) and has also been repeatedly used in different experiments from 2009. Hybridization analysis allowed for finding differentially expressed genes due to the effect of induced over-expression of the DEVH1-encoding gene in the knock-in promastigote line compared to the control line. Genes involved in parasite infectivity and survival such as the HASP/SHERP gene cluster and an amastin gene or redox homeostasis genes are significantly down-regulated in the pTEX-DEVH1 knock-in promastigote line, whereas genes related to growth are up-regulated. This is in agreement with previous experimental data supporting that L. infantum DEVH1 knock-in promastigotes are able to recover the growth rate when stress conditions are removed.
2022-08-03 | GSE202674 | GEO
Project description:Leishmania is the unicellular parasite transmitted by phlebotomine sand fly bite. It exists in two different forms; extracellular promastigotes, occurring in the gut of sand flies, and intracellular, round-shaped amastigotes residing mainly in vertebrate macrophages. As amastigotes originating from infected animals are often present in insufficient quality and quantity, two alternative types of amastigotes were introduced for laboratory experiments: axenic amastigotes and amastigotes from macrophages infected in vitro. Nevertheless, there is very little information about the degree of similarity/difference among these three types of amastigotes on proteomic level, whose comparison is crucial for assessing the suitability of using alternative types of amastigotes in experiments. In this study, L. mexicana amastigotes obtained from lesion of infected BALB/c mice were proteomically compared with alternatively cultivated amastigotes (axenic and macrophage-derived ones). Amastigotes of all three types were isolated, individually treated and analysed by LC-MS/MS proteomic analysis with quantification using TMT10-plex isobaric labeling. Significant differences were observed in the abundance of metabolic enzymes, virulence factors and proteins involved in translation and condensation of DNA. The most pronounced differences were observed between axenic amastigotes and lesion-derived amastigotes, macrophage-derived amastigotes were mostly intermediate between axenic and lesion-derived ones.
2023-03-11 | PXD036664 | Pride
Project description:Parasitic protozoa of the genus Leishmania are obligatory intracellular parasites that caus e human leishmaniasis . During their life, they cycle between the phagolysosome of mammalian macrophages ( round intracellular amastigotes ) , and the mid - gut of female sand flies ( elongated extracellular promastigotes ) . Shifting axenic promastigotes to a lysosome - like environment ( pH 5.5 and 37 ̊C , 5% C O 2 ) initiate s their development into amastigotes. Previous studies suggested a role for protein kinase A in differentiation initiation . In this study we assessed this hypothesis by describ ing a new , divergent , regulatory subunit of protein kinase A (LdPKAR3) whose phosphorylation is regulated by the differentiation signal . This protein exists exclusively in the genome s of Leishmania and T rypano soma cruzi , both obligatory intracellular parasites . W hile the C - terminal half of this protein is conserved , the N - termin al region is divergent and much longer than the consensus R subunits . We found that LdPKAR3 is bound to the subpellicular microtubules cell cortex via a formin FH2 domain at its N - terminal tip. Immunoprecipitation , fluorescence resonance energy transfer ( FRET ) , proteomics, and 3D modeling analyses indicated that LdPKAR3 associate s with the PKA catalytic subunit 3 (C3) to form a PKA holoenzyme , indicating that R3 is a true PKA regulatory subunit. In promastigotes, LdPKA R3 recruits C3 to the central region of the subpellicular microtubules , where it determines the ir elongated shape . Deleti ng either R3 or C3 resulted in significant rounding of most of the promastigote population . Adding back the full - length wild type genes restored the elongat e shape of promastigotes. This is the first time that a PKA regulatory s ubunit has been shown to play a role in Leishmania morphogenesis
2024-03-21 | PXD025222 | Pride
Project description:Protozoa of the genus Leishmania are the causative agents of leishmaniasis in humans. These parasites cycle between promastigotes in the sand fly mid-gut and amastigotes in phagolysosome of mammalian macrophages. During infection, host up-regulate nitric oxide synthase and parasite induce host arginase expression, both of which use arginine as a substrate. These elevated activities deplete macrophage arginine pools, a situation that invading Leishmania must overcome since it is an essential amino acid. Leishmania donovani imports exogenous arginine via a mono-specific amino acid transporter (AAP3) and utilizes it primarily through the polyamine pathway to provide precursors for trypanothione biosynthesis. Here we report the discovery of a pathway whereby promastigote and amastigote forms of the Leishmania sense the lack of environmental arginine and respond with rapid up-regulation in AAP3 expression and activity, as well as several other transporters. Significantly, this arginine deprivation response is also activated in parasites during macrophage infection. Phosphoproteomic analyses of L. donovani promastigotes have implicated a Mitogen-Activated Protein Kinase 2 (MPK2)-mediated signaling cascade in this response and L. mexicana mutants lacking MPK2 are unable to respond to arginine deprivation. In this study, we established that Leishmania cells sense the absence of arginine in their environment; both in culture (axenic promastigotes and amastigotes) and in macrophages during infection (amastigotes). This study describes the first amino acid deprivation sensing mechanism and the pathway that transduce this response, and reveals a novel host-pathogen metabolic interplay. Total RNA from Ten Leishmania donovani samples were analyzed using RNA-Seq. Cells from two life stages (promastigotes and amastigotes) were grown in axenic culture in the presence and absense of arginine. For each condition two biological replicates were grown and analyzed. In addition two macrophage grown amastigotes were analyzed.
2016-08-01 | E-GEOD-71572 | biostudies-arrayexpress
Project description:Protozoa of the genus Leishmania are the causative agents of leishmaniasis in humans. These parasites cycle between promastigotes in the sand fly mid-gut and amastigotes in phagolysosome of mammalian macrophages. During infection, host up-regulate nitric oxide synthase and parasite induce host arginase expression, both of which use arginine as a substrate. These elevated activities deplete macrophage arginine pools, a situation that invading Leishmania must overcome since it is an essential amino acid. Leishmania donovani imports exogenous arginine via a mono-specific amino acid transporter (AAP3) and utilizes it primarily through the polyamine pathway to provide precursors for trypanothione biosynthesis. Here we report the discovery of a pathway whereby promastigote and amastigote forms of the Leishmania sense the lack of environmental arginine and respond with rapid up-regulation in AAP3 expression and activity, as well as several other transporters. Significantly, this arginine deprivation response is also activated in parasites during macrophage infection. Phosphoproteomic analyses of L. donovani promastigotes have implicated a Mitogen-Activated Protein Kinase 2 (MPK2)-mediated signaling cascade in this response and L. mexicana mutants lacking MPK2 are unable to respond to arginine deprivation. In this study, we established that Leishmania cells sense the absence of arginine in their environment; both in culture (axenic promastigotes and amastigotes) and in macrophages during infection (amastigotes). This study describes the first amino acid deprivation sensing mechanism and the pathway that transduce this response, and reveals a novel host-pathogen metabolic interplay.
2016-08-01 | GSE71572 | GEO
Project description:The leishmaniases are globally important parasitic diseases for which no human vaccines are currently available. To facilitate vaccine development, we conducted an open label observational study to establish a controlled human infection model of sand fly-transmitted cutaneous leishmaniasis caused by L. major. Between 24th January and 12th August 2022, we exposed 14 (8F, 6M) participants to infected sand flies. The primary objective was to demonstrate effectiveness (attack rate) and safety (absence of CL lesion at 12 months), whereas secondary and exploratory objectives included rate of lesion development, parasite load and analysis of local immune responses using immunohistology and spatial transcriptomics. We estimated a take rate for CL development of 64% (9/14) based on all participants, increasing to 82% (9/11) if only participants with confirmed bites are included. Lesion development was terminated by therapeutic biopsy in 10 participants with confirmed bites. 30% (3/10) had either one (2/10) or two (1/10) lesion recurrences between 4-8 months after biopsy that were treated successfully with cryotherapy. No severe or serious adverse events were recorded, but scarring was evident as expected. All participants were lesion-free at long-term (>12 month) follow up. We provide the first comprehensive map of immune cell distribution and cytokine/chemokine expression in human CL lesions, revealing discrete immune niches. This controlled human infection model offers opportunities for rapid vaccine candidate selection and a greater understanding of immune-mediated protection and pathology.
2024-04-30 | GSE263298 | GEO