Cytogenetic and molecular characterization of ribosomic DNA from triatomines

• Grant number: 05/55804-0
• Support Opportunities: Regular Research Grants
• Duration: October 01, 2006 - September 30, 2009
• Field of knowledge: Biological Sciences - Genetics - Animal Genetics
• Principal Investigator: Ester Tartarotti
• Grantee: Ester Tartarotti
• Host Institution: Instituto de Biociências, Letras e Ciências Exatas (IBILCE). Universidade Estadual Paulista (UNESP). Campus de São José do Rio Preto. São José do Rio Preto , SP, Brazil

Abstract

The aim of this project is to analyse ribosomic DNA in triatomines species of the genus Rhodnius, Triatoma and Panstrongylus that will be supplied by the Insectarium of the Special Health Service, in the city of Araraquara, São Paulo state, which is run by the Department of Epidemiology, Faculty of Public Health, São Paulo (SP). These insects are the vectors of Chagas' disease, one of the most prominent public health problems among South America countries with pronounced relevance among heart diseases in the continent. Entomologic studies have shown that secondary species of triatomines have been increasing their density in the homes in the recent years. There is a concern about these species in Chagas' disease transmission, because, such species, in some areas of the country, have already began a peri-dwelling and dwelling cycle. The elimination of the disease is being hampered by progressive political indifference; there is a continuous risk of vectorial transmission due to insect survival and low activity of sanitary surveillance. With respect to the classification, the triatomines are insects belonging to the Heteroptera suborder, Reduviidae family, Triatominae subfamily and their origin is possibly poliphyletic. However, the triatomines still do not have a clear phylogeny solved and their true ancestrality continues to be the object researchs. Studies with molecular markers contribute to understanding the phylogeny of group and, besides these markers, additional studies can be realized with chromosomes, because, cytogenetic data supplies important information at cellular level. Ribosomic DNA is used in phylogenetic studies at several taxonomic levels, from phylum to populations. A high degree of molecular polymorphism has been found in this genic area in insects. The intention is to analyse ribosomic DNA (rDNA) by the sequencing of the ribosomal DNA ITS-1 transcribed intergenic spacer (ITS-1) and for molecular cytogenetic (FISH) specific probes for 28S rDNA will be used. In this manner, the phylogeny and evolution of the group will be analyzed based on the alignment of ribosomic DNA intergenic sequences, as well as for the rDNA localization "in situ". This study will contribute to a better understanding of genetic relationships between the triatatomies species and will lead to a better knowledge about biology of these insects. The degree of insect prevalence will also be evaluated in the northwest area of São Paulo state, through an index of notifications in the health units of the area, so that, together with bibliographical surveys, a contribution can be made to institutions of sanitary surveillance on the importance of the control of Chagas' disease. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

ALEVI, K. C. C.; RODAS, L. A. C.; TARTAROTTI, E.; AZEREDO-OLIVEIRA, M. T. V.; GUIRADO, M. M.. Entoepidemiology of Chagas disease in the Western region of the State of Sao Paulo from 2004 to 2008, and cytogenetic analysis in Rhodnius neglectus (Hemiptera, Triatominae). Genetics and Molecular Research, v. 14, n. 2, p. 5775-5784, 2015. (13/19764-0, 05/55804-0)