RESUMO
Whole mitogenome sequences (mtDNA) have been exploited for insect ecology studies, using them as molecular markers to reconstruct phylogenies, or to infer phylogeographic relationships and gene flow. Recent Anopheles phylogenomic studies have provided information regarding the time of deep lineage divergences within the genus. Here we report the complete 15,393 bp mtDNA sequences of Anopheles aquasalis, a Neotropical human malaria vector. When comparing its structure and base composition with other relevant and available anopheline mitogenomes, high similarity and conserved genomic features were observed. Furthermore, 22 mtDNA sequences comprising anopheline and Dipteran sibling species were analyzed to reconstruct phylogenies and estimate dates of divergence between taxa. Phylogenetic analysis using complete mtDNA sequences suggests that A. aquasalis diverged from the Anopheles albitarsis complex ~28 million years ago (MYA), and ~38 MYA from Anopheles darlingi. Bayesian analysis suggests that the most recent ancestor of Nyssorhynchus and Anopheles + Cellia was extant ~83 MYA, corroborating current estimates of ~79-100 MYA. Additional sampling and publication of African, Asian, and North American anopheline mitogenomes would improve the resolution of the Anopheles phylogeny and clarify early continental dispersal routes.
Assuntos
Anopheles/classificação , Anopheles/genética , Genoma Mitocondrial , Genômica , Filogenia , Filogeografia , Animais , Composição de Bases , Biologia Computacional/métodos , Evolução Molecular , Genômica/métodos , Humanos , Anotação de Sequência Molecular , Mosquitos Vetores/classificação , Mosquitos Vetores/genética , Análise de Sequência de DNA , Sequenciamento Completo do GenomaRESUMO
Salivary gland polytene chromosomes of 4th instar Anopheles darlingi Root were examined from multiple locations in the Brazilian Amazon. Minor modifications were made to existing polytene photomaps. These included changes to the breakpoint positions of several previously described paracentric inversions and descriptions of four new paracentric inversions, two on the right arm of chromosome 3 and two on the left arm of chromosome 3 that were found in multiple locations. A total of 18 inversions on the X (n = 1) chromosome, chromosome 2 (n = 7) and 3 (n = 11) were scored for 83 individuals from Manaus, Macapá and Porto Velho municipalities. The frequency of 2Ra inversion karyotypes in Manaus shows significant deficiency of heterozygotes (p < 0.0009). No significant linkage disequilibrium was found between inversions on chromosome 2 and 3. We hypothesize that at least two sympatric subpopulations exist within the An. darlingi population at Manaus based on inversion frequencies.
Assuntos
Anopheles/genética , Inversão Cromossômica/genética , Insetos Vetores/genética , Cromossomos Politênicos/genética , Glândulas Salivares , Animais , Anopheles/classificação , Brasil , Mapeamento Cromossômico , Insetos Vetores/classificaçãoRESUMO
Salivary gland polytene chromosomes of 4th instar Anopheles darlingi Root were examined from multiple locations in the Brazilian Amazon. Minor modifications were made to existing polytene photomaps. These included changes to the breakpoint positions of several previously described paracentric inversions and descriptions of four new paracentric inversions, two on the right arm of chromosome 3 and two on the left arm of chromosome 3 that were found in multiple locations. A total of 18 inversions on the X (n = 1) chromosome, chromosome 2 (n = 7) and 3 (n = 11) were scored for 83 individuals from Manaus, Macapá and Porto Velho municipalities. The frequency of 2Ra inversion karyotypes in Manaus shows significant deficiency of heterozygotes (p < 0.0009). No significant linkage disequilibrium was found between inversions on chromosome 2 and 3. We hypothesize that at least two sympatric subpopulations exist within the An. darlingi population at Manaus based on inversion frequencies.
Assuntos
Animais , Anopheles/genética , Inversão Cromossômica/genética , Insetos Vetores/genética , Cromossomos Politênicos/genética , Glândulas Salivares , Anopheles/classificação , Brasil , Mapeamento Cromossômico , Insetos Vetores/classificaçãoRESUMO
The Psorophora confinnis complex is currently composed of three species--Psorophora confinnis sensu stricto (Lynch Arribalzaga) in South America, Psorophora columbiae (Dyar and Knab) in North America, and Psorophora jamaicensis (Theobald) in the Caribbean. Members of the complex are of considerable importance as vectors of arboviruses, for example, Venezuelan equine encephalitis virus, and are significant biting pests throughout their range. The biological and geographic boundaries of Ps. confinnis and Ps. columbiae are unclear. In fact, the name Ps. columbiae is presently designated as "provisional." In this article, we aim to clarify the taxonomy and geographic distributions of species within the Ps. confinnis complex. A population genetics approach was employed using gene and genotypic frequency data at 26 isozyme loci. The results suggest that the Ps. confinnis complex in North and South America is composed of four species. Ps. confinnis s.s. and Ps. columbiae are distinct species in South and North America, respectively. Populations in Colombia, South America, formally designated as Ps. funiculus (Dyar) and populations in the southwestern United States and western Mexico, formally designated Ps. toltecum (Dyar and Knab), are distinct species. Psorophora toltecum and Psorophora funiculus species names should be resurrected from synonymy. In addition we identified a Ps. columbiae and Ps. toltecum hybrid zone in central Texas in a region described as being one of 13 North American suture zones, being geographical areas in which closely related species occur in sympatry and frequently hybridize.
Assuntos
Culicidae/fisiologia , Variação Genética , Genótipo , Distribuição Animal , Animais , Culicidae/genética , Feminino , Hibridização Genética , Masculino , Dados de Sequência Molecular , América do Norte , Filogenia , Análise de Sequência de DNA , América do Sul , Especificidade da EspécieRESUMO
Genetic diversity among three field populations of Lutzomyia longipalpis in Colombia was studied using isozyme analysis. Study sites were as much as 598 km apart and included populations separated by the eastern Cordillera of the Andes. Genetic variability among populations, estimated by heterozygosity, was within values typical for insects in general (8.1 per cent). Heterozygosity for field populations were compared with a laboratory colony from Colombia (Melgar colony) and were only slightly lower. These results suggest that establishment and long term maintenance of the Melgar colony has had little effect on the level of isozyme variability it carries. Genetic divergences between populations was evaluated using estimates of genetic distance. Genetic divergence among the three field populations was low (D=0.021), suggesting that they represent local populations within a single species. Genetic distance between field populations and the Melgar colony was also low (D=0.016), suggesting that this colony population does not depart significantly from natural populations. Finally, comparisons were made between Colombian populations and colonies from Brazil and Costa Rica. Genetic distance values were high between Colombian and both Brazil and Costa Rica colony populations (D=0.199 and 0.098 respectively) providing additional support for our earlier report that populations from the three countries represent distinct species.
Assuntos
Animais , Variação Genética , Isoenzimas/análise , Psychodidae/genética , Brasil , Colômbia , Costa RicaRESUMO
Debido a inconsistencias en el patrón de la transmisión de la malaria en las zonas geográficas donde habita Anopheles pseudopunctipennis pseudopunctipennis, se investigó la posibilidad de que este vector representara un complejo de especie. Se hicieron estudios de hibridación, localización electroforética de enzimas y análisis restrictivo del ADN en mosquitos capturados en nueve localidades de México, Bolivia y el Perú. La esterilidad de las generaciones resultantes de cruzamientos entre hembras mexicanas y machos sudamericanos, dos localizaciones enzimáticas capaces de diferenciar ambas poblaciones y el valor de 0,13 de distancia genética comprobaron la presencia de un complejo de especie probablemente producido por especiación alopátrica. Se concluye que es necesario establecer la extensión geográfica de las especies recién descubiertas por su efecto potencial en el control de la malaria.
Assuntos
Anopheles , Malária , Controle de Mosquitos , México , Bolívia , Peru , América LatinaRESUMO
Debido a inconsistencias en el patron de la transmision de la malaria en las zonas geográficas donde habita Anopheles pseudopunctipennis pseudopunctipennis, se investigo la posibilidad de que este vector representara un complejo de especie. Se hicieron estudios de hibridacion, localizacion electroforetica de enzimas y analisis restrictivo del ADN en mosquitos capturados en nueve localidades de México, Bolivia y el Perú. La esterilidad de las generaciones resultantes de cruzamientos entre hembras mexicanas y machos sudamericanos, dos localizaciones enzimaticas capaces de diferenciar ambas poblaciones y el valor de 0,13 de distancia genetica comprobaron la presencia de un complejo de especie probablemente producido por especiacion alopatrica. Se concluye que es necesario establecer la extension geográfica de las especies recien descubiertas por su efecto potencial en el control de la malaria
Assuntos
Anopheles/genética , Malária/transmissão , Bolívia , América Latina , México , Controle de Mosquitos , PeruRESUMO
This article was also published in spanish in the Bol. Oficina Sanit. Panam, Vol. 113, No. 4, 1992