Leishmania amazonensis strain:IFLA/BR/67/PH8
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ABSTRACT:
PROVIDER: PRJNA244311 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Iron uptake controls the generation of Leishmania infective forms through regulation of ROS levels .
| PRJNA177795 | ENA
Project description:Leishmania amazonensis strain:MHOM/BR/71973/M2269 Genome sequencing
| PRJNA221875 | ENA
Project description:Leishmania amazonensis Transcriptome or Gene expression
| PRJNA292915 | ENA
Project description:GENE EXPRESSION PROFILING AND MOLECULAR CHARACTERIZATION OF ANTIMONY RESISTANCE IN Leishmania amazonensis
| PRJNA135277 | ENA
Project description:In this study we report the complete repertoire of 2'-O-methylation sites present in the rRNA of Leishmania amazonensis rRNAs and a subset of small RNAs using RibOxi-seq.
2024-05-01 | GSE186879 | GEO
Project description:During its life cycle Leishmania undergoes extreme environmental changes, alternating between insect vectors and vertebrate hosts. In mammals the parasites replicate within parasitophorous vacuoles of macrophages, compartments that contain low concentrations of iron. Here we show that stimulation of iron transport, which is induced in Leishmania amazonensis by an iron-poor environment, triggers the differentiation of avirulent promastigotes into virulent amastigotes. Iron depletion from the culture medium triggered expression of the LIT1 ferrous iron transporter, growth arrest, and differentiation of wild type promastigotes into infective amastigotes. In contrast, LIT1 null promastigotes showed continued exponential growth in iron-poor media, followed by massive cell death. Iron depletion from the medium and LIT1 upregulation increased iron superoxide dismutase activity (FeSOD) in wild type, but not in LIT1 null parasites. Notably, the superoxide-generating drug menadione or H2O2 were sufficient to trigger differentiation of wild type promastigotes into fully infective amastigotes. On the other hand, LIT1 null promastigotes accumulated superoxide radical and initiated amastigote differentiation after exposure to H2O2, but not to menadione. Our results reveal a novel role for FeSOD activity and reactive oxygen species (ROS) in orchestrating the differentiation of Leishmania infective stages, in a process regulated by iron availability.
2012-12-15 | GSE41641 | GEO
Project description:In mammals, resident dermal macrophages (MΦs) are subverted by Leishmania (L.) amazonensis amastigotes as host cells permissive for parasite multiplication. These Leishmania are living within a communal parasitophorous vacuole (PV) and are expected to trigger unique MΦ transcriptional signatures. We performed a transcription profiling of mouse MΦs harboring amastigotes to get insights into their reprogramming as host cells for parasite multiplication. BALB/c mouse bone marrow-derived MΦs were either loaded or not with four amastigotes on average. Twenty four hours later, when amastigotes multiply, total RNA from MΦ cultures was prepared, amplified and hybridized onto Affymetrix Mouse430_2 GeneChips®. The outcome recorded a total of 1,248 probe-sets showing significant differential expression. Comparable fold-change values for a handful of genes were obtained between Affymetrix technology and the more sensitive RTqPCR method. Ingenuity Pathway Analysis software® pinpointed the up-regulation of the sterol biosynthesis pathway (P-value = 1.31e-02) involving several genes (1.95 to 4.30 fold-change values), and the modulation of various genes involved in polyamine synthesis and in pro/counter-inflammatory signaling. Our findings suggest that amastigotes exploit the MΦ lipid and polyamine pathways to multiply efficiently, and induce a counter-inflammatory environment to expand their dermis niche.
2009-01-01 | GSE11497 | GEO
Project description:Background: Drug resistance is a major problem in leishmaniasis chemotherapy. RNA expression profiling using DNA microarrays is a suitable approach to study simultaneous events leading to a drug-resistance phenotype. Genomic analysis has been performed primarily with Old World Leishmania species and here we investigate molecular alterations in antimony resistance in the New World species L. amazonensis. Methods/Principal Findings: We selected populations of L. amazonensis for resistance to antimony by step-wise drug pressure. Gene expression of highly resistant mutants was studied using DNA microarrays. RNA expression profiling of antimony-resistant L. amazonensis revealed the overexpression of genes involved in drug resistance including the ABC transporter MRPA and several genes related to thiol metabolism. The MRPA overexpression was validated by quantitative real-time PCR and further analysis revealed that this increased expression was correlated to gene amplification as part of extrachromosomal linear amplicons in some mutants and as part of supernumerary chromosomes in other mutants. The expression of several other genes encoding hypothetical proteins but also nucleobase and glucose transporter encoding genes were found to be modulated. Conclusions/Significance: Mechanisms classically found in Old World antimony resistant Leishmania were also highlighted in New World antimony-resistant L. amazonensis. These studies were useful to the identification of resistance molecular markers.
2011-06-11 | GSE26159 | GEO
Project description:To determine the modulation of gene expression of C57BL/6 and DBA/2 BMDLs in the presence of living intracellular Leishmania amazonensis amastigotes
2013-01-07 | GSE38261 | GEO
Project description:During its life cycle Leishmania undergoes extreme environmental changes, alternating between insect vectors and vertebrate hosts. In mammals the parasites replicate within parasitophorous vacuoles of macrophages, compartments that contain low concentrations of iron. Here we show that stimulation of iron transport, which is induced in Leishmania amazonensis by an iron-poor environment, triggers the differentiation of avirulent promastigotes into virulent amastigotes. Iron depletion from the culture medium triggered expression of the LIT1 ferrous iron transporter, growth arrest, and differentiation of wild type promastigotes into infective amastigotes. In contrast, LIT1 null promastigotes showed continued exponential growth in iron-poor media, followed by massive cell death. Iron depletion from the medium and LIT1 upregulation increased iron superoxide dismutase activity (FeSOD) in wild type, but not in LIT1 null parasites. Notably, the superoxide-generating drug menadione or H2O2 were sufficient to trigger differentiation of wild type promastigotes into fully infective amastigotes. On the other hand, LIT1 null promastigotes accumulated superoxide radical and initiated amastigote differentiation after exposure to H2O2, but not to menadione. Our results reveal a novel role for FeSOD activity and reactive oxygen species (ROS) in orchestrating the differentiation of Leishmania infective stages, in a process regulated by iron availability. Four samples were obtained in total from wild-type L. amazonensis promastigotes grown for 24 hours in culture. Two of these samples derived from medium with iron and two from mediam without iron.These two samples derived from each culture served as biological replicates.
2012-12-15 | E-GEOD-41641 | biostudies-arrayexpress