ABSTRACT. The biological characteristics of Aedes aegypti (Diptera, Culicidae), which is a vector of dengue and yellow fever, make this organism a good model for studying population structure and the events that may influence it under the effect of human activity. We assessed the genetic variability of five A. aegypti populations using RAPD-PCR technique and six primers. Four populations were from Brazil and one was from the USA. A total of 165 polymorphic DNA loci were generated. Considering the six primers and the five populations, the mean value of inter-population genetic diversity (Gst) was 0.277, which is considered high according to the Wright classification. However, pairwise comparisons of the populations gave variable Gst values ranging from 0.044 to 0.289. This variation followed the population's geographic distance to some extent but was also influenced by human activity. The lowest Gst values were obtained in the comparison of populations from cities with intensive commercial and medical contacts. These mosquito populations were previously classified as insecticide resistant, susceptible, or with decreased susceptibility; this parameter apparently had an effect on the Gst values obtained in the pairwise comparisons.
Abstract:The clinical efficacy of oral hydroxyurea (HU) in the treatment of the sickle cell disease (SCD) is already proven. However, side-effects on reproduction and development still cause concerns, mainly in long term treatments. We used Drosophila melanogaster as a model organism in the study of this subject. This species has been considered favorable for studying human diseases and responses to drugs because both organisms share more than 50% of the genes for disease and exhibit a very similar drug metabolism. In addition, D. melanogaster allows laboratory approaches that are not possible in humans. We analyzed the impact of the concentrations HU 0.1 and HU 0.25 on productivity, oviposition rate, emergence period duration, mortality and development time from egg to adult. HU affected all these traits, showing dose dependence. The frequency of mating, and duration of premating and mating times of flies were also analyzed in treatments with HU 0.25. Considering all the traits, the treatments decreased the productivity, oviposition rate and frequency of mating, and increased the emergence period duration, mortality rate from egg to adult and development time. The premating and mating times duration were affected in a more complex way. On the basis of the knowledge that HU affects DNA synthesis and repair, and other data available in the literature, we raised hypotheses to explain the present observations. The results and hypotheses suggested new approaches for further studies of particular and important aspects. In general, this study reinforces the validity of the concern with HU side-effects.Keywords: Emergence period duration, impaired effect of hydroxyurea, mortality from egg to adult, number of progeny, oviposition rate.
A sublethal dose of Imidacloprid, considered actually as the most widely used insecticide against biting and sucking insects, was administered to Drosophila melanogaster for detecting effects on biological traits. The choice of this species as organism-model potentially opens the possibility to explore more deeply the processes involved in those effects because, among other reasons, there is a large accumulation of biological knowledge on this species and because it propitiates multiple approaches in laboratory and nature. The flies were treated along 15 consecutive generations. F1 parents were randomly taken among virgin flies from the stocks, but the parents of the successive generations were the first 15 couples emerged in the previous one. The number of progeny (productivity) and the duration of the emergence period were analyzed in every generation revealing insecticide toxicity in 12 of the 15 generations. The observation of an increase in the number of progeny over the generations, which occurred in both control and treated experiments (although maintaining higher productivity in the control), suggested an effect of the use of the first 15 emerged couples in successive generations. A comparative analysis of the mortality of the F15 adult flies exposed to imidacloprid by contact, which involved flies from the control, treatment and from the stocks that originated the experiments, reinforced this idea, indicating a genetic interplay of the emergence speed with productivity and adult tolerance to the insecticide, a subject that may be better explored in another study. Toxicity was also observed for the traits longevity, viability during development from egg to adult and oviposition rate. Considering the present intensive use of imidacloprid, the harmful effects observed in these important biological characteristics may be considered able to decrease the adaptive value of D. melanogaster populations exposing them at risk of decline.
Interspecific hybrids and constructed research models have provided information on intracellular interactions. We used two introgressed, chromosomally differentiated strains (H4 and H2) derived from F1 hybrids of crosses between D. prosaltans females and D. saltans males. In H4, the D. prosaltans chromosomes were eliminated. In H2, a mixture was maintained, preserving the entire genome of D. prosaltans (except the Y chromosome) and parts of the D. saltans genome. The IIR arm and a segment of chromosome III were eliminated. A third strain, used for comparison, was a normal D. prosaltans strain (P). This study aimed primarily to analyze the effect on the reproductive characteristics productivity (number of progeny) and sex-ratio caused by How to cite this paper: de França Patarro, T. and de Campos Bicudo, H.E.M. (2019) Intracellular Interactions in the Reproduction Control of Introgressed Strains Involving Species from Drosophila saltans Group (Sophophora Subgenus) with Emphasis to the Effect of Wolbachia Infection.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.