Recent advances in trypanosomatid research: genome organization, expression, metabolism, taxonomy and evolution

Abstract

Unicellular flagellates of the family Trypanosomatidae are obligatory parasites of invertebrates, vertebrates and plants. Dixenous species are aetiological agents of a number of diseases in humans, domestic animals and plants. Their monoxenous relatives are restricted to insects. Because of the high biological diversity, adaptability to dramatically different environmental conditions, and omnipresence, these protists have major impact on all biotic communities that still needs to be fully elucidated. In addition, as these organisms represent a highly divergent evolutionary lineage, they are strikingly different from the common 'model system' eukaryotes, such as some mammals, plants or fungi. A number of excellent reviews, published over the past decade, were dedicated to specialized topics from the areas of trypanosomatid molecular and cell biology, biochemistry, host-parasite relationships or other aspects of these fascinating organisms. However, there is a need for a more comprehensive review that summarizing recent advances in the studies of trypanosomatids in the last 30 years, a task, which we tried to accomplish with the current paper.

Molecular Characterization of Tc964, A Novel Antigenic Protein from Trypanosoma cruzi

“…Orthologues were identified in species of the Trypanosoma genus, T. rangeli (79% of sequence identity) and T. brucei (50%), in the Leishmania genus (48%), in monoxenous trypanosomatids (47%) and in the free-living Bodo saltans (32%). The phylogenetic relationships inferred from the tree based on Tc964-orthologues fit well with current taxonomy of kinetoplastids [33]. However, by BLAST searches at NCBI, no clear orthologues were found in organisms other than kinetoplastids.…”

Catalase compromises the development of the insect and mammalian stages of Trypanosoma brucei

“…The most commonly studied ones are the procyclic stage (PCF) in the insect’s midgut and the bloodstream stage (BSF) in the mammalian host . When transferred from one host to another and during the interstage transitions between different host tissues and compartments, the parasite is exposed to a plethora of oxidative stresses .…”

“…via blood feeding [1]. To prosper in both the insect vector and and compartments, the parasite is exposed to a plethora of oxidative stresses [4,5].…”

If host is refractory, insistent parasite goes berserk: Trypanosomatid Blastocrithidia raabei in the dock bug Coreus marginatus

“…The diversity of monoxenous trypanosomatids has been previously studied using mainly two different molecular markers-18S rRNA and SL RNA [5], for which the datasets overlap only partially. Therefore, we decided to use both of them in order to better understand the phylogenetic affinities of B. raabei.…”

“…Although insect-restricted (monoxenous) trypanosomatids do not have such a strong impact, studying them is as important because these species serve as models for the abovementioned pathogens and because of many peculiarities, inherent to the whole family: polycistronic transcription and trans-splicing of nuclear protein-encoding genes, complex organization of kinetoplast DNA, RNA editing, etc. [5]. In the last few years monoxenous species started attracting even more attention owing to the ability of some flagellates to survive in humans [6][7][8][9][10][11], negative effect on economically important insects [12,13] and symbiotic relationships with intracellular bacteria [14][15][16][17][18].…”