Dados do Trabalho

Título

Comparative molecular analysis of Lutzomyia umbratilis, the main vector of Leishmania (viannia) guyanensis, from endemic and non-endemic leishmaniasis regions of the Amazon state.

Introdução

The epidemiological profile of the American Cutaneous Leishmaniasis in the Amazonian cities of Manacapuru (MNP) and Rio Preto da Eva (RPE), separated by the Negro River, differs, RPE being an endemic area of the disease and MNP showing no significant number of cases. Previous studies with insects from both localities detected differences in the interactions of the vector Lutzomyia umbratilis and the circulating parasite Leishmania (Viannia) guyanensis.   

Objetivo (s)

Proteomic analyzes of MNP and RPE sand fly midguts; transcription level determination of genes related to the proteins of interest observed in the proteomics in carcasses and intestinal tracts of insects from both localities in the Amazon and from Lutzomyia longipalpis; microbiota analyzes of sandflies from both locations based on the results obtained in proteomics;

Material e Métodos

Midgut proteomics analyses using sand flies from MNP and RPE. RT-qPCR was performed using insects from the two locations and L. longipalpis to compare the level of transcripts in carcasses and intestinal tracts.   

Resultados e Conclusão

A total of 3292 proteins were identified in the proteomic analysis. Among the proteins, eight were selected for transcriptional validation, based on the criteria of amount of reads and the potential to impact on the vectorial capacity of insects. Of these eight proteins, four were only detected in MNP: SARA, Citocromo P450, CysPc and XPR1. The other proteins analyzed were detected both in MNP and RPE, but they had a fold change greater than 2 or less than 0.5 in MNP as PATH and Paramiosin. With these targets defined, RT-qPCR was performed using insects from the two locations to compare the level of transcripts in carcasses and intestinal tracts. Our results showed that most of these transcripts are upregulated in MNP, similar to the data from the proteomic analysis and are likely relevant in the mechanism of parasite transmission by the insect. The targets SARA and CysPc were selected for transcriptional analyzes in L. longipalpis, since this permissive species is kept in our colony, as opposed to L. umbratilis, which is not colonized. L. longipalpis will be used as a model for gene silencing  followed by infection with Leishmania to evaluate their role in infection. Using the proteomic data, we also identified bacterial proteins and analyzed the microbiota composition of both populations. The possible implications of these data are being verified in relation to the different vectorial capacity of these sand fly populations.   

Palavras Chave

Leishmania; Sand fly; Vectorial capacity