Leishmaniinae: evolutionary inferences based on protein expression profiles (PhyloQuant) congruent with phylogenetic relationships amongLeishmania, Endotrypanum, Porcisia, Zelonia, Crithidia,andLeptomonas

Abstract

Evolutionary relationships among parasites of the subfamily Leishmaniinae, which comprises pathogen agents of leishmaniasis, were inferred based on differential protein expression profiles from mass spectrometry-based quantitative data using the PhyloQuant method. Evolutionary distances following identification and quantification of protein and peptide abundances using Proteome Discoverer (PD) and MaxQuant (MQ) softwares were estimated for 11 species from 6 Leishmaniinae genera. Results clustered all dixenous species of the genus Leishmania, subgenera L. (Leishmania), L. (Viannia) and L. (Mundinia), sister to the dixenous species of genera Endotrypanum and Porcisia. Positioned basal to the assemblage formed by all these parasites were the species of genera Zelonia, Crithidia and Leptomonas, so far described as monoxenous of insects although eventually reported from humans. Inferences based on protein expression profiles were congruent with currently established phylogeny using DNA sequences. Our results reinforce PhyloQuant as a valuable approach to infer evolutionary relationships consistent with genera, subgenera, and species-specific biological characteristics, able to resolve within Leishmaniinae, which is comprised of very tightly related trypanosomatids that are just beginning to be phylogenetically unravelled. In additional to evolutionary history, mapping of species-specific protein expression is paramount to understand differences in infection processes, disease presentations, tissue tropisms, potential to jump from insects to vertebrates including humans, and potential targets for species-specific diagnostic and drug development. Keywords: Evolution, Leishmaniasis, Leishmaniinae, PhyloQuant, proteome, taxonomy, tropical diseases, Trypanosomatidae