| Full text | |
| Author(s): |
Dias, Fabricio C.
;
Ruiz, Jeronimo C.
;
Lopes, Wilton C. Z.
;
Squina, Fabio M.
;
Renzi, Adriana
;
Cruz, Angela K.
[6]
;
Tosi, Luiz R. O.
Total Authors: 7
|
| Document type: | Journal article |
| Source: | Parasitology Research; v. 101, n. 3, p. 667-676, Aug. 2007. |
| Field of knowledge: | Biological Sciences - Biochemistry |
| Abstract | |
Resistance to antimonials is a major problem when treating visceral leishmaniasis in India and has already been described for New World parasites. Clinical response to meglumine antimoniate in patients infected with parasites of the Viannia sub-genus can be widely variable, suggesting the presence of mechanisms of drug resistance. In this work, we have compared L. major and L. braziliensis mutants selected in different drugs. The cross-resistance profiles of some cell lines resembled those of mutants bearing H locus amplicons. However, amplified episomal molecules were exclusively detected in L. major mutants. The analysis of the L. braziliensis H region revealed a strong conservation of gene synteny. The typical intergenic repeats that are believed to mediate the amplification of the H locus in species of the Leishmania sub-genus are partially conserved in the Viannia species. The conservation of these non-coding elements in equivalent positions in both species is indicative of their relevance within this locus. The absence of amplicons in L. braziliensis suggests that this species may not favour extra-chromosomal gene amplification as a source of phenotypic heterogeneity and fitness maintenance in changing environments. (AU) | |
| FAPESP's process: | 05/02997-6 - Caracterizacao dos mecanismos de resistencia a antimoniais elicitados em diferentes especies do parasita protozoario leishmania. |
| Grantee: | Wilton Carlos Zanetti Lopes |
| Support Opportunities: | Scholarships in Brazil - Doctorate |
| FAPESP's process: | 04/03397-0 - Estudo de fenótipos associados ao locus H de Leishmania spp.: caracterização de genes desconhecidos, efeito da amplificação e sinergismo de genes |
| Grantee: | Luiz Ricardo Orsini Tosi |
| Support Opportunities: | Regular Research Grants |
| FAPESP's process: | 04/15619-7 - Caracterizacao de mecanismos de resistencia a terbinafina em diferentes especies de leishmania. |
| Grantee: | Fabrício César Dias |
| Support Opportunities: | Scholarships in Brazil - Doctorate |
| FAPESP's process: | 01/02527-9 - Nocaute sistematico de genes em (leishmania major). utilizacao de sistema "mariner mos1" de transposicao "in vitro". |
| Grantee: | Fábio Márcio Squina |
| Support Opportunities: | Scholarships in Brazil - Doctorate |