ABSTRACT
Abstract Londrina is the fourth most populous city in southern Brazil. Its subtropical weather with rain in all seasons, as well as its high population density, make the city perfect for the Aedes aegypti (Linnaeus, 1762) life cycle. Over the last few years, Londrina presented high infestation indexes and was one of the cities with the most reported cases of dengue. Uncontrolled use of synthetic insecticides may influence the mosquito's genetic composition. In this paper, we studied mitochondrial DNA and kdr mutations in Aedes aegypti. The analysis of the ND4 gene in 330 specimens showed the presence of 27 haplotypes. The pyrethroid resistance alleles (kdr) evaluated are present in the collected populations, with a 50% frequency of the Val1016Ile and 48% of the Phe1534Cys mutations. Such analysis of the mutations in the populations collected at the State University of Londrina's campus - a microenvironment that differs from the rest of the city - showed frequencies of 57% and 62%, respectively. The low gene flow observed, Nm = 0.11 and Nm = 0.10, along with the elevated differentiation, Fst = 0.19 and Fst = 0.18, among populations suggest an influence of genetic drift. The strong presence of resistance alleles kdr in the city is evident, which demonstrates that even with the interruption of the use of pyrethroids by the National Dengue Control Program, resistance may be maintained due to domestic use. Thus, the results have shown the need for genetic monitoring, alongside other entomological surveillance monitoring tools, to create strategies of mosquito control.
ABSTRACT
Objective To investigate the sequence characteristic of black bear's mitochondrial NADH-ubiquinone oxidoreductase chain 4 gene(ND4).Methods Primers were designed according to certain species' NADH-ubiquinone oxidoreductase ND4 in which the DNA sequence had been reported.The DNA sequence was amplified by PCR from the Asian black bear Sichuan subspecies's(Ursus thibetanus mupinensis)hair-follicle tissue total DNA and were analyzed with its amino acid sequence.Results The ND4 gene sequence length was 1 402 bp and contained a 1 377-nucleotide open reading frame encoding 459 amino acid residues.The amino acid sequence's pI was 9.37 and weight was 51.5?10 3.The DNA sequence and corresponding amino acid sequence of black bear's ND4 gene had the high similarity with those of other mammalian animals' ND4 gene,and the similarity was 89% to 91% and 94% to 95%.The result of phylogenetic tree was basically consistent with the traditional species system phylogenetic relations.Topology prediction showed the Asian black bear Sichuan subspecies's ND4 proteins contained N-glycosylation site,kinase C phosphorylation sites,casein kinase Ⅱ phosphorylation site,N-myristoylation site and leucine-rich region.In addition,black bear's ND4 protein contained leucine zipper pattern and Leucine-rich region.Conclusion The mammalia animal's ND4 gene has the high conservative nature.The pretein coded by ND4 gene has high uniformity in the function.