Phenotypic diversity and selection maintain Leishmania amazonensis infectivity in BALB/c mouse model.

Leishmania are protozoan parasites that show remarkable diversity, as revealed by the various clinical forms of leishmaniasis, which can range from mild skin lesions to severe metastatic cutaneous/mucosal lesions. The exact nature and extent of Leishmania phenotypic diversity in establishing infection is not fully understood. In order to try to understand some aspects of this diversity, we subcutaneously infected BALB/c mice with first and second generation subclones of a L.

TbFlabarin, a flagellar protein of Trypanosoma brucei, highlights differences between Leishmania and Trypanosoma flagellar-targeting signals.

TbFlabarin is the Trypanosoma brucei orthologue of the Leishmania flagellar protein LdFlabarin but its sequence is 33% shorter than LdFlabarin, as it lacks a C-terminal domain that is indispensable for LdFlabarin to localize to the Leishmania flagellum. TbFlabarin is mainly expressed in the procyclic forms of the parasite and localized to the flagellum, but only when two palmitoylable cysteines at positions 3 and 4 are present. TbFlabarin is more strongly attached to the membrane fraction than its Leishmania counterpart, as it resists complete solubilization with as much as 0.

Constitutive mosaic aneuploidy is a unique genetic feature widespread in the Leishmania genus.

Using fluorescence in situ hybridization, we determined the ploidy of four species of Leishmania: Leishmania infantum, Leishmania donovani, Leishmania tropica and Leishmania amazonensis. We found that each cell in a strain possesses a combination of mono-, di- and trisomies for all chromosomes; ploidy patterns were different among all strains/species. These results extend those we previously described in Leishmania major, demonstrating that mosaic aneuploidy is a genetic feature widespread to the Leishmania genus.

LdFlabarin, a new BAR domain membrane protein of Leishmania flagellum.

During the Leishmania life cycle, the flagellum undergoes successive assembly and disassembly of hundreds of proteins. Understanding these processes necessitates the study of individual components. Here, we investigated LdFlabarin, an uncharacterized L.

The leishmania ARL-1 and Golgi traffic.

We present here the characterisation of the Leishmania small G protein ADP-Ribosylation Factor-Like protein 1 (ARL-1). The ARL-1 gene is present in one copy per haploid genome and conserved among trypanosomatids. It encodes a protein of 20 kDa, which is equally expressed in the insect promastigote and mammalian amastigote forms of the parasite.

Flagellar length depends on LdARL-3A GTP/GDP unaltered cycling in Leishmania amazonensis.

We have shown previously that expression of the GTP-blocked form of the small G protein LdARL-3A/Q70L led to a marked shortening of Leishmania promastigotes flagella. In contrast, there was no effect with the T30N mutant, thought to represent the GDP-blocked form. However, recent data, obtained with human ARF-6, a member of the same family of G proteins, revealed that the corresponding mutant T27N was nucleotide-free and that the GDP-blocked form was the T44N mutant.

A soluble pyrophosphatase, a key enzyme for polyphosphate metabolism in Leishmania.

We report the functional characterization in Leishmania amazonensis of a soluble pyrophosphatase (LaVSP1) that localizes in acidocalcisomes, a vesicular acidic compartment. LaVSP1 is preferentially expressed in metacyclic forms. Experiments with dominant negative mutants show the requirement of LaVSP1 functional expression for metacyclogenesis and virulence in mice.

LdARL-1 His-tagged recombinant protein: purification by immobilized metal affinity expanded bed adsorption.

Previously we have cloned three ADP-ribosylation factor-like (ARL) genes from the parasitic protozoan Leishmania donovani: LdARL-3A and 3B, LdARL-1. LdARL-3A was previously purified as an active native form, which was able to bind GTP in vitro. In this paper, we have performed the production and the purification of Histidine-tagged (His-tagged) LdARL-1 recombinant protein by immobilized metal affinity chromatography (IMAC) using expanded bed adsorption (EBA) technology.

Trypanosomatid flagellum biogenesis: ARL-3A is involved in several species.

Overexpression in Leishmania amazonensis promastigotes of the GTPase-deficient small G protein LdARL-3A-Q70L specifically provokes the loss of the flagella without affecting cell viability and body size. However, motility is lost and, remarkably, cells do not survive in the insect vector Lutzomyia longipalpis gut, leading to interruption of parasite transmission. We report here that overexpression of the same protein in Leishmania major, Leishmania donovani, and Crithidia fasciculata also led to significant alterations of the flagella.

Abortive infection of Lutzomyia longipalpis insect vectors by aflagellated LdARL-3A-Q70L overexpressing Leishmania amazonensis parasites.

Leishmania donovani ADP-ribosylation factor-like protein 3A (LdARL-3A) is a small G protein isolated from the protozoan parasite L. donovani with no defined physiological function. Previously [Cuvillier, A.