Last data update: Apr 22, 2024. (Total: 46599 publications since 2009)
Records 1-6 (of 6 Records) |
Query Trace: Monteiro FA [original query] |
---|
Under pressure: phenotypic divergence and convergence associated with microhabitat adaptations in Triatominae (preprint)
Abad-Franch F , Monteiro FA , Pavan MG , Patterson JS , Bargues MD , Zuriaga MÁ , Aguilar M , Beard CB , Mas-Coma S , Miles MA . bioRxiv 2020 2020.07.28.224535 Background Triatomine bugs, the vectors of Chagas disease, associate with vertebrate hosts in highly diverse ecotopes. When these blood-sucking bugs adapt to new microhabitats, their phenotypes may change. Although understanding phenotypic variation is key to the study of adaptive evolution and central to phenotype-based taxonomy, the drivers of phenotypic change and diversity in triatomines remain poorly understood.Methods/Findings We combined a detailed phenotypic appraisal (including morphology and morphometrics) with mitochondrial cytb and nuclear ITS2 DNA-sequence analyses to study Rhodnius ecuadoriensis populations from across the species’ range. We found three major, naked-eye phenotypic variants. Southern-Andean bugs (SW Ecuador/NW Peru) from house and vertebrate-nest microhabitats are typical, light-colored, small bugs with short heads/wings. Northern-Andean bugs (W Ecuador wet-forest palms) are dark, large bugs with long heads/wings. Finally, northern-lowland bugs (coastal Ecuador dry-forest palms) are light-colored and medium-sized. Wing and (size-free) head shapes are similar across Ecuadorian populations, regardless of habitat or naked-eye phenotype, but distinct in Peruvian bugs. Bayesian phylogenetic and multispecies-coalescent DNA-sequence analyses strongly suggest that Ecuadorian and Peruvian populations are two independently-evolving lineages, with little within-lineage structuring/differentiation.Conclusions We report sharp naked-eye phenotypic divergence of genetically similar Ecuadorian R. ecuadoriensis (house/nest southern-Andean vs. palm-dwelling northern bugs; and palm-dwelling Andean vs. lowland); and sharp naked-eye phenotypic similarity of typical, yet genetically distinct, southern-Andean bugs from house and nest (but not palm) microhabitats (SW Ecuador vs. NW Peru). This remarkable phenotypic diversity within a single nominal species likely stems from microhabitat adaptations possibly involving predator-driven selective pressure (yielding substrate-matching camouflage coloration) and a shift from palm-crown to vertebrate-nest microhabitats (yielding smaller bodies and shorter heads and wings). These findings shed new light on the origins of phenotypic diversity in triatomines, warn against excess reliance on phenotype-based triatomine-bug taxonomy, and confirm the Triatominae as an informative model-system for the study of phenotypic change under ecological pressure.Author summary Triatomine bugs feed on the blood of vertebrates including humans and transmit the parasite that causes Chagas disease. The bugs, of which 150+ species are known, are highly diverse in size, shape, and color. Some species look so similar that they are commonly confused, whereas a few same-species populations look so different that they were thought to be separate species. Despite the crucial role of naked-eye phenotypes in triatomine-bug identification and classification (which are essential for vector control-surveillance), the origins of this variation remain unclear. Here, we describe a striking case of phenotypic divergence, with genetically similar bugs looking very different from one another, and phenotypic convergence, with bugs from two genetically distinct populations (likely on their way to speciation) looking very similar – and all within a single nominal species, Rhodnius ecuadoriensis. Phenotypically divergent populations occupy different ecological regions (wet vs. dry) and microhabitats (palm-crowns vs. vertebrate nests), whereas convergent populations occupy man-made and nest (but not palm) microhabitats. These findings suggest that triatomines can ‘respond’ to ecological novelty by changing their external, naked-eye phenotypes as they adapt to new microhabitats. We therefore warn that phenotypic traits such as overall size or color may confound triatomine-bug species identification and classification. |
Under pressure: phenotypic divergence and convergence associated with microhabitat adaptations in Triatominae.
Abad-Franch F , Monteiro FA , Pavan MG , Patterson JS , Bargues MD , Zuriaga MÁ , Aguilar M , Beard CB , Mas-Coma S , Miles MA . Parasit Vectors 2021 14 (1) 195 BACKGROUND: Triatomine bugs, the vectors of Chagas disease, associate with vertebrate hosts in highly diverse ecotopes. It has been proposed that occupation of new microhabitats may trigger selection for distinct phenotypic variants in these blood-sucking bugs. Although understanding phenotypic variation is key to the study of adaptive evolution and central to phenotype-based taxonomy, the drivers of phenotypic change and diversity in triatomines remain poorly understood. METHODS/RESULTS: We combined a detailed phenotypic appraisal (including morphology and morphometrics) with mitochondrial cytb and nuclear ITS2 DNA sequence analyses to study Rhodnius ecuadoriensis populations from across the species' range. We found three major, naked-eye phenotypic variants. Southern-Andean bugs primarily from vertebrate-nest microhabitats (Ecuador/Peru) are typical, light-colored, small bugs with short heads/wings. Northern-Andean bugs from wet-forest palms (Ecuador) are dark, large bugs with long heads/wings. Finally, northern-lowland bugs primarily from dry-forest palms (Ecuador) are light-colored and medium-sized. Wing and (size-free) head shapes are similar across Ecuadorian populations, regardless of habitat or phenotype, but distinct in Peruvian bugs. Bayesian phylogenetic and multispecies-coalescent DNA sequence analyses strongly suggest that Ecuadorian and Peruvian populations are two independently evolving lineages, with little within-lineage phylogeographic structuring or differentiation. CONCLUSIONS: We report sharp naked-eye phenotypic divergence of genetically similar Ecuadorian R. ecuadoriensis (nest-dwelling southern-Andean vs palm-dwelling northern bugs; and palm-dwelling Andean vs lowland), and sharp naked-eye phenotypic similarity of typical, yet genetically distinct, southern-Andean bugs primarily from vertebrate-nest (but not palm) microhabitats. This remarkable phenotypic diversity within a single nominal species likely stems from microhabitat adaptations possibly involving predator-driven selection (yielding substrate-matching camouflage coloration) and a shift from palm-crown to vertebrate-nest microhabitats (yielding smaller bodies and shorter and stouter heads). These findings shed new light on the origins of phenotypic diversity in triatomines, warn against excess reliance on phenotype-based triatomine-bug taxonomy, and confirm the Triatominae as an informative model system for the study of phenotypic change under ecological pressure . |
Genome of Rhodnius prolixus, an insect vector of Chagas disease, reveals unique adaptations to hematophagy and parasite infection.
Mesquita RD , Vionette-Amaral RJ , Lowenberger C , Rivera-Pomar R , Monteiro FA , Minx P , Spieth J , Carvalho AB , Panzera F , Lawson D , Torres AQ , Ribeiro JM , Sorgine MH , Waterhouse RM , Montague MJ , Abad-Franch F , Alves-Bezerra M , Amaral LR , Araujo HM , Araujo RN , Aravind L , Atella GC , Azambuja P , Berni M , Bittencourt-Cunha PR , Braz GR , Calderon-Fernandez G , Carareto CM , Christensen MB , Costa IR , Costa SG , Dansa M , Daumas-Filho CR , De-Paula IF , Dias FA , Dimopoulos G , Emrich SJ , Esponda-Behrens N , Fampa P , Fernandez-Medina RD , da Fonseca RN , Fontenele M , Fronick C , Fulton LA , Gandara AC , Garcia ES , Genta FA , Giraldo-Calderon GI , Gomes B , Gondim KC , Granzotto A , Guarneri AA , Guigo R , Harry M , Hughes DS , Jablonka W , Jacquin-Joly E , Juarez MP , Koerich LB , Latorre-Estivalis JM , Lavore A , Lawrence GG , Lazoski C , Lazzari CR , Lopes RR , Lorenzo MG , Lugon MD , Majerowicz D , Marcet PL , Mariotti M , Masuda H , Megy K , Melo AC , Missirlis F , Mota T , Noriega FG , Nouzova M , Nunes RD , Oliveira RL , Oliveira-Silveira G , Ons S , Pagola L , Paiva-Silva GO , Pascual A , Pavan MG , Pedrini N , Peixoto AA , Pereira MH , Pike A , Polycarpo C , Prosdocimi F , Ribeiro-Rodrigues R , Robertson HM , Salerno AP , Salmon D , Santesmasses D , Schama R , Seabra-Junior ES , Silva-Cardoso L , Silva-Neto MA , Souza-Gomes M , Sterkel M , Taracena ML , Tojo M , Tu ZJ , Tubio JM , Ursic-Bedoya R , Venancio TM , Walter-Nuno AB , Wilson D , Warren WC , Wilson RK , Huebner E , Dotson EM , Oliveira PL . Proc Natl Acad Sci U S A 2015 112 (48) 14936-14941 Rhodnius prolixus not only has served as a model organism for the study of insect physiology, but also is a major vector of Chagas disease, an illness that affects approximately seven million people worldwide. We sequenced the genome of R. prolixus, generated assembled sequences covering 95% of the genome ( approximately 702 Mb), including 15,456 putative protein-coding genes, and completed comprehensive genomic analyses of this obligate blood-feeding insect. Although immune-deficiency (IMD)-mediated immune responses were observed, R. prolixus putatively lacks key components of the IMD pathway, suggesting a reorganization of the canonical immune signaling network. Although both Toll and IMD effectors controlled intestinal microbiota, neither affected Trypanosoma cruzi, the causal agent of Chagas disease, implying the existence of evasion or tolerance mechanisms. R. prolixus has experienced an extensive loss of selenoprotein genes, with its repertoire reduced to only two proteins, one of which is a selenocysteine-based glutathione peroxidase, the first found in insects. The genome contained actively transcribed, horizontally transferred genes from Wolbachia sp., which showed evidence of codon use evolution toward the insect use pattern. Comparative protein analyses revealed many lineage-specific expansions and putative gene absences in R. prolixus, including tandem expansions of genes related to chemoreception, feeding, and digestion that possibly contributed to the evolution of a blood-feeding lifestyle. The genome assembly and these associated analyses provide critical information on the physiology and evolution of this important vector species and should be instrumental for the development of innovative disease control methods. |
On palms, bugs, and Chagas disease in the Americas
Abad-Franch F , Lima MM , Sarquis O , Gurgel-Goncalves R , Sanchez-Martin M , Calzada J , Saldana A , Monteiro FA , Palomeque FS , Santos WS , Angulo VM , Esteban L , Dias FB , Diotaiuti L , Bar ME , Gottdenker NL . Acta Trop 2015 151 126-41 Palms are ubiquitous across Neotropical landscapes, from pristine forests or savannahs to large cities. Although palms provide useful ecosystem services, they also offer suitable habitat for triatomines and for Trypanosoma cruzi mammalian hosts. Wild triatomines often invade houses by flying from nearby palms, potentially leading to new cases of human Chagas disease. Understanding and predicting triatomine-palm associations and palm infestation probabilities is important for enhancing Chagas disease prevention in areas where palm-associated vectors transmit T. cruzi. We present a comprehensive overview of palm infestation by triatomines in the Americas, combining a thorough reanalysis of our published and unpublished records with an in-depth review of the literature. We use site-occupancy modeling (SOM) to examine infestation in 3590 palms sampled with non-destructive methods, and standard statistics to describe and compare infestation in 2940 palms sampled by felling-and-dissection. Thirty-eight palm species (18 genera) have been reported to be infested by approximately 39 triatomine species (10 genera) from the USA to Argentina. Overall infestation varied from 49.1-55.3% (SOM) to 62.6-66.1% (dissection), with important heterogeneities among sub-regions and particularly among palm species. Large palms with complex crowns (e.g., Attalea butyracea, Acrocomia aculeata) and some medium-crowned palms (e.g., Copernicia, Butia) are often infested; in slender, small-crowned palms (e.g., Euterpe) triatomines associate with vertebrate nests. Palm infestation tends to be higher in rural settings, but urban palms can also be infested. Most Rhodnius species are probably true palm specialists, whereas Psammolestes, Eratyrus, Cavernicola, Panstrongylus, Triatoma, Alberprosenia, and some Bolboderini seem to use palms opportunistically. Palms provide extensive habitat for enzootic T. cruzi cycles and a critical link between wild cycles and transmission to humans. Unless effective means to reduce contact between people and palm-living triatomines are devised, palms will contribute to maintaining long-term and widespread, albeit possibly low-intensity, transmission of human Chagas disease. Graphical Abstract summary Palms are widely distributed throughout the Americas, as this 1853 map by Alfred Russel Wallace shows. This distribution almost perfectly matches the distribution of endemic human Chagas disease. Palm-living triatomine bugs make up the bridge between palms and disease. The bugs share palm crown habitats with Trypanosoma cruzi hosts. Flying from palms, infected vectors invade houses and can transmit the parasite to humans. Understanding the ecological links between palms and the parasite's vectors and hosts will be crucial for the long-term prevention of human Chagas disease. |
Phylogeographic pattern and extensive mitochondrial DNA divergence disclose a species complex within the Chagas disease vector Triatoma dimidiata
Monteiro FA , Peretolchina T , Lazoski C , Harris K , Dotson EM , Abad-Franch F , Tamayo E , Pennington PM , Monroy C , Cordon-Rosales C , Salazar-Schettino PM , Gómez-Palacio A , Grijalva MJ , Beard CB , Marcet PL . PLoS One 2013 8 (8) e70974 BACKGROUND: Triatoma dimidiata is among the main vectors of Chagas disease in Latin America. However, and despite important advances, there is no consensus about the taxonomic status of phenotypically divergent T. dimidiata populations, which in most recent papers are regarded as subspecies. METHODOLOGY AND FINDINGS: A total of 126 cyt b sequences (621 bp long) were produced for specimens from across the species range. Forty-seven selected specimens representing the main cyt b clades observed (after a preliminary phylogenetic analysis) were also sequenced for an ND4 fragment (554 bp long) and concatenated with their respective cyt b sequences to produce a combined data set totalling 1175 bp/individual. Bayesian and Maximum-Likelihood phylogenetic analyses of both data sets (cyt b, and cyt b+ND4) disclosed four strongly divergent (all pairwise Kimura 2-parameter distances >0.08), monophyletic groups: Group I occurs from Southern Mexico through Central America into Colombia, with Ecuadorian specimens resembling Nicaraguan material; Group II includes samples from Western-Southwestern Mexico; Group III comprises specimens from the Yucatán peninsula; and Group IV consists of sylvatic samples from Belize. The closely-related, yet formally recognized species T. hegneri from the island of Cozumel falls within the divergence range of the T. dimidiata populations studied. CONCLUSIONS: We propose that Groups I-IV, as well as T. hegneri, should be regarded as separate species. In the Petén of Guatemala, representatives of Groups I, II, and III occur in sympatry; the absence of haplotypes with intermediate genetic distances, as shown by multimodal mismatch distribution plots, clearly indicates that reproductive barriers actively promote within-group cohesion. Some sylvatic specimens from Belize belong to a different species - likely the basal lineage of the T. dimidiata complex, originated ~8.25 Mya. The evidence presented here strongly supports the proposition that T. dimidiata is a complex of five cryptic species (Groups I-IV plus T. hegneri) that play different roles as vectors of Chagas disease in the region. |
A nuclear single-nucleotide polymorphism (SNP) potentially useful for the separation of Rhodnius prolixus from members of the Rhodnius robustus cryptic species complex (Hemiptera: Reduviidae).
Pavan MG , Mesquita RD , Lawrence GG , Lazoski C , Dotson EM , Abubucker S , Mitreva M , Randall-Maher J , Monteiro FA . Infect Genet Evol 2013 14 (1) 426-433 The design and application of rational strategies that rely on accurate species identification are pivotal for effective vector control. When morphological identification of the target vector species is impractical, the use of molecular markers is required. Here we describe a non-coding, single-copy nuclear DNA fragment that contains a single-nucleotide polymorphism (SNP) with the potential to distinguish the important domestic Chagas disease vector, Rhodnius prolixus, from members of the four sylvatic Rhodnius robustus cryptic species complex. A total of 96 primer pairs obtained from whole genome shotgun sequencing of the R. prolixus genome (12,626 random reads) were tested on 43 R. prolixus and R. robustus s.l. samples. One of the seven amplicons selected (AmpG) presented a SNP, potentially diagnostic for R. prolixus, on the 280th site. The diagnostic nature of this SNP was then confirmed based on the analysis of 154 R. prolixus and R. robustus s.l. samples representing the widest possible geographic coverage. The results of a 60% majority-rule Bayesian consensus tree and a median-joining network constructed based on the genetic variability observed reveal the paraphyletic nature of the R. robustus species complex, with respect to R. prolixus. The AmpG region is located in the fourth intron of the Transmembrane protein 165 gene, which seems to be in the R. prolixus X chromosome. Other possible chromosomal locations of the AmpG region in the R. prolixus genome are also presented and discussed. (2013 Elsevier B.V.) |
- Page last reviewed:Feb 1, 2024
- Page last updated:Apr 22, 2024
- Content source:
- Powered by CDC PHGKB Infrastructure