Dataset Information

Proteomic analysis of the secretome of seven Leishmania species

ABSTRACT: This study provides a comprehensive analysis of the secretome of seven different Leishmania species (six main human pathogenic species: L. donovani, L. infantum, L. braziliensis, L. major, L. amazonensis, L. tropica) and L. tarentolae, non-pathogenic to humans, produced by promastigotes cultured in serum-free conditions. The exhaustive analysis of the protein content of the secretome using mass spectrometry led to the identification of common and unique proteins, as well as useful insights on the relation between secretome content and pathogenesis. The biological relevance of the secretome is undeniable and, in the particular case of Leishmania parasites, it is a crucial player in the host-pathogen interactions which dictate the outcome of infection and disease severity. This study actively contributes to current knowledge on Leishmania biology and the generated datasets are an addition to current databases, associating the identified proteins with subcellular localization and putative extracellular functions.

INSTRUMENT(S): LTQ Orbitrap XL

ORGANISM(S): Leishmania <genus>

DISEASE(S): Leishmaniasis

SUBMITTER: Functional Proteomics Platform FPP

LAB HEAD: Jean-Loup Lemesre

PROVIDER: PXD023228 | Pride | 2021-11-29

REPOSITORIES: Pride

ACCESS DATA

Similar Datasets

Project description:This study describes the application of the LongSAGE methodology to study the gene expression profile in Leishmania infantum chagasi. A tag library was created using the LongSAGE method and consisted of 14,208 tags of 17 bases. Of these, 8,427 (59.3%) were distinct. BLAST research of the 1,645 most abundant tags showed that 12.8% of them identified the coding sequences of genes, while 82% (1,349/1,645) identified one or more genomic sequences that did not correspond with open reading frames. Only 5.2% (84/1,645) of the tags were not aligned to any position in the L. infantum genome. The UTR size of Leishmania and the lack of CATG sites in some transcripts were decisive for the generation of tags in these regions. LongSAGE revealed the gene expression profile in promastigotes of L. i. chagasi. Additional analysis will allow a better understanding of the expression profile and discovering the key genes in this life cycle. The I-SAGETM Long kit (Invitrogen) was used to construct the L. i. chagasi library according to the manufacturer's recommendations. The following were included among the main steps: polyadenylates mRNAs were captured by oligo (dT) linked to magnetic beads and used for cDNA synthesis. The cDNA was digested with 60 U of NlaIII (anchoring enzyme) and the 3' ends of the cDNAs were isolated using the beads. The resulting cDNA 3' was divided into two equal portions and connected to two LongSAGE adapters, A and B. The long tags were released by the enzyme MmeI and linked to form ~130 bp ditags. Dilutions of 1:40 of the product were amplified in 27 PCR cycles (300 reactions in total). The precipitated PCR products were separated on 12% polyacrylamide gel and the 130 bp bands were cut out and the precipitated DNA was digested with NlaIII. The digestion products were separated on 12% polyacrylamide gel and ~34 bp ditags were cut out and linked to form concatemers. The concatemers were separated on 6% polyacrylamide gel and the fractions of 250-500 and 500-800pb were isolated and cloned into pZErO-1 vector digested with SphI. Vectors with concatemers were cloned in E. coli DH10b by electroporation and the isolated recombinant vectors were used as template for sequencing in the ABI Prism 3100 (Applied Biosystems).

Project description:Among the most central questions in Leishmania research is why some species remain in the skin dermis at the site of infection by the sand fly vector whereas other species migrate to visceral organs where they cause fatal visceral leishmaniasis. Although L. donovani is the species typically responsible for visceral leishmaniasis, an atypical L. donovani strain is the etiologic agent for cutaneous leishmaniasis in Sri Lanka. To identify molecular determinants for visceral disease, we have analysed the phenotype and genotype of two L. donovani clinical isolates from Sri Lanka where one isolate was derived from a cutaneous leishmaniasis patient (CL) and the other from a visceral leishmaniasis patient (VL). These isolates cause dramatically different pathology when introduced into mice; notably the CL isolate has lost the ability to survive in visceral organs while the VL isolate was highly virulent in visceral organs of BALB/c mice. Whole genome sequencing of the CL and VL isolates revealed that these genomes were very similar as there were no gene deletions and few individual gene amplifications. Indels resulting in frame shifts and loss/gain of stop codons resulted in 13 distinct pseudogenes present in each of the CL and VL isolates. There were 154 non-synonymous SNPs specific to the CL isolate and 193 non-synonymous SNPs specific to the VL isolate. Genome wide gene expression analysis revealed several transcript level differences, including the A2 virulence gene resulting in higher expression of A2 proteins in the VL isolate than in the CL isolate. Genotypic variations relevant to pathology and tropism in Leishmania can be interrogated by reverse genetics. Experimentally increasing A2 expression in the CL isolate through gene transfer significantly increased itM-bM-^@M-^Ys ability to survive in the spleen of BALB/c mice and conversely, down-regulating A2 expression in the VL isolate abrogated attenuated its survival in BALB/c mice. These observations reveal that there are relatively few genetic differences between the CL and VL isolates apart from the A2 genes, but collectively these have profound effects on human disease and experimentally infected mice. 6 Samples in total, 3 each from VL and CL causing isolates were analyzed by Splice Leader RNASeq. These three samples from each of the isolates were grown to form one of the following three lifestages, Promastigotes, Macrophage derived Amastigotes, Axenic Amastigotes.

Project description:SbIII clonal mutants and an isogenic WT clonal line. Genomic DNA from clonal WT or mutants were digested and hybridized to whole genome DNA microarrays. Antimonials are still the mainstay of treatment against Leishmaniasis but in the past decade resistance has been a severe threat. We carried out short read next generation sequencing (NGS) and comparative genomic hybridization (CGH) of three independent Leishmania major antimony resistant mutants. Copy number variations were consistently detected in both NGS and CGH where several chromosomal aneuploidies were correlated to antimony resistance. A major attribute of antimony resistance was a novel terminal deletion of variable length (67kb-204kb) of the polyploid chromosome 31 in the three mutants and was experimentally validated. Terminal deletion in two mutants occurred at the level of inverted repeated sequences in chromosome 31. AQP1 (LmjF.31.0020), a gene encoding for an aquaglyceroporin, which facilitates uptake of trivalent metalloids, was a part of the deleted region. Transfection of AQP1 into resistant mutants rendered them hypersensitive to SbIII. CGH, NGS and Southern blot analysis also highlighted a novel stable, intrachromosomal amplification of a subtelomeric locus on chromosome 34 in one mutant. This region encoded redox enzymes like ascorbate dependent peroxidase (APX) and glucose-6-phosphate dehydrogenase (G6PDH) and overexpression of the genes coding for these enzymes in revertant backgrounds demonstrated resistance to SbIII and protection from reactive oxygen species (ROS) accumulation. Generation of G6PDH null mutant in one revertant exhibited SbIII sensitivity and protection from ROS which were rescued in the add back. Our genomic analyses and parallel functional validation highlighted novel genomic rearrangements, functionally important resistant loci and the implication of new genes in antimony resistance in Leishmania. This submission represents the microarray component of the study 3 biological replicates of each sample

Dataset Information

Proteomic analysis of the secretome of seven Leishmania species

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure