scholarly journals The smORF-containing gene mille-pattes is required for moulting and Trypanosoma cruzi metacyclogenesis in the Chagas disease vector Rhodnius prolixus

2020 ◽  
Author(s):  
Carina Azevedo ◽  
Bruno Rodrigues ◽  
Sandy Alves ◽  
Lupis Ribeiro ◽  
Carlos Logullo ◽  
...  
Keyword(s):  
Trypanosoma Cruzi ◽  
Chagas Disease ◽  
Disease Transmission ◽  
Postembryonic Development ◽  
Rhodnius Prolixus ◽  
Open Reading Frames ◽  
Disease Spread ◽  
Polished Rice ◽  
Triatomine Bugs ◽  
Small Open Reading Frames

SummaryChagas disease is estimated to affect 8 million people worldwide and is responsible for approximately 10,000 deaths in Latin America every year. Control of the triatomine bugs that transmit the flagellated parasite Trypanosoma cruzi has been the most successful strategy to avoid disease spread. Genes containing small open reading frames (smORFs, < 100 amino acids) constitute a putative reservoir of new vector control targets, since hundreds of these genes are present in insect genomes. Here, we show that the prototypic smORF-containing gene mille-pattes/polished-rice/tarsalless (mlpt/pri/tal) is essential for postembryonic development of the kissing bug Rhodnius prolixus and for T. cruzi metacyclogenesis during the nymphal stages. Injection of double-stranded RNA against mlpt (Rp-dsmlpt) during the nymphal stages leads to a plethora of phenotypes, which impair postembryonic development. First, fourth or fifth stage nymphs injected with Rp-dsmlpt do not moult even in the presence of the ecdysone receptor (EcR) mRNA. Second, Rp-dsmlpt nymphs have defects in gut morphology, delayed haemoglobin digestion, and decreased defecation volume compared with those of the control nymphs. Third, Rp-mlpt knockdown inhibits T. cruzi differentiation to the trypomastigote infective stage (metacyclogenesis) inside the R. prolixus gut. Overall, our study is the first to provide evidence that a smORF-containing gene regulates vector physiology and parasitic cycle thus enabling the development of novel molecular strategies to eliminate Chagas disease transmission.

scholarly journals Automated identification of insect vectors of Chagas disease in Brazil and Mexico: the Virtual Vector Lab

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e3040 ◽  
Author(s):  
Rodrigo Gurgel-Gonçalves ◽  
Ed Komp ◽  
Lindsay P. Campbell ◽  
Ali Khalighifar ◽  
Jarrett Mellenbruch ◽  
...  
Keyword(s):  
Trypanosoma Cruzi ◽  
Chagas Disease ◽  
Disease Transmission ◽  
Automated System ◽  
Correct Identification ◽  
Insect Vectors ◽  
Automated Identification ◽  
Considerable Potential ◽  
Triatomine Bugs ◽  
Fully Automated System

Identification of arthropods important in disease transmission is a crucial, yet difficult, task that can demand considerable training and experience. An important case in point is that of the 150+ species of Triatominae, vectors ofTrypanosoma cruzi, causative agent of Chagas disease across the Americas. We present a fully automated system that is able to identify triatomine bugs from Mexico and Brazil with an accuracy consistently above 80%, and with considerable potential for further improvement. The system processes digital photographs from a photo apparatus into landmarks, and uses ratios of measurements among those landmarks, as well as (in a preliminary exploration) two measurements that approximate aspects of coloration, as the basis for classification. This project has thus produced a working prototype that achieves reasonably robust correct identification rates, although many more developments can and will be added, and—more broadly—the project illustrates the value of multidisciplinary collaborations in resolving difficult and complex challenges.

scholarly journals Distribution and natural infection status of synantrophic triatomines (Hemiptera: Reduviidae), vectors of Trypanosoma cruzi, reveals new epidemiological scenarios for chagas disease in the Highlands of Colombia

2021 ◽  
Vol 15 (7) ◽  
pp. e0009574
Author(s):  
Omar Cantillo-Barraza ◽  
Manuel Medina ◽  
Sara Zuluaga ◽  
María Isabel Blanco ◽  
Rodrigo Caro ◽  
...  
Keyword(s):  
Spatial Analysis ◽  
Trypanosoma Cruzi ◽  
Chagas Disease ◽  
Natural Infection ◽  
Significant Risk ◽  
Rhodnius Prolixus ◽  
The Other ◽  
Infection Status ◽  
Triatomine Bugs ◽  
Increased Risk

Introduction Updating the distribution and natural infection status of triatomine bugs is critical for planning, prioritizing, and implementing strategies to control Chagas disease (CD), especially after vector reduction programs. After carrying out a control program, the Department of Boyaca contains the highest number of Colombian municipalities certified by PAHO to be free of intradomiciliary transmission of Trypanosoma cruzi by Rhodnius prolixus. The present work describes the spatial distribution, natural infection (NI), and molecular characterization of T. cruzi in synanthropic triatomines from the Department of Boyaca in 2017 and 2018. Materials and methods An entomological survey was conducted in 52 municipalities in Boyaca known to have had previous infestations of triatomine bugs. Insects were collected through active searches carried out by technical personnel from the Secretary of Health and community members using Triatomine Collection Stations (PITs-acronym in Spanish). For evaluation of natural infection, triatomines were identified morphologically and grouped in pools of one to five individuals of the same species collected in the same household. DNA derived from the feces of each pool of insects was analyzed by PCR for the presence of T. cruzi using primers flanking the satellite DNA of the parasite. SL-IR primers were used to differentiate TCI from the other DTUs and to identify different genotypes. The distribution of the collected triatomines was analyzed to determine any vector hotspots using spatial recreation. Results A total of 670 triatomine bugs was collected, belonging to five species: Triatoma dimidiata (73.2%), Triatoma venosa (16.7%), Panstrongylus geniculatus (5.7%), Rhodnius prolixus (4.4%), and Panstrongylus rufotuberculatus (0.4%), from 29 of the 52 municipalities. In total, 71.6% of the bugs were collected within houses (intradomiciliary) and the rest around the houses (peridomiciliary). Triatoma dimidiata was the most widely distributed species and had the highest natural infection index (37.8%), followed by T. venosa and P. geniculatus. TcI was the only DTU found, with the TcI Dom genotype identified in 80% of positive samples and TcI sylvatic in the other insects. Spatial analysis showed clusters of T. dimidiata and T. venosa in the northeast and southwest regions of Boyaca. Conclusions After some municipalities were certified free of natural transmission within houses (intradomiciliary transmission) of T. cruzi by R. prolixus, T. dimidiata has become the most prevalent vector present, and represents a significant risk of resurgent CD transmission. However, T. venosa, P. geniculatus, and P. rufotuberculatus also contribute to the increased risk of transmission. The presence of residual R. prolixus may undo the successes achieved through vector elimination programs. The molecular and spatial analysis used here allows us to identify areas with an ongoing threat of parasite transmission and improve entomological surveillance strategies.

scholarly journals Mother-child transmission of Chagas disease: could coinfection with human immunodeficiency virus increase the risk?

2009 ◽  
Vol 42 (2) ◽  
pp. 107-109 ◽  
Author(s):  
Pablo Gustavo Scapellato ◽  
Edgardo Gabriel Bottaro ◽  
María Teresa Rodríguez-Brieschke
Keyword(s):  
Human Immunodeficiency Virus ◽  
Trypanosoma Cruzi ◽  
Chagas Disease ◽  
Vertical Transmission ◽  
Disease Transmission ◽  
Transmission Rate ◽  
Buffy Coat ◽  
Child Transmission ◽  
Serological Tests ◽  
Immunodeficiency Virus

A study was conducted on all newborns from mothers with Chagas disease who were attended at Hospital Donación F. Santojanni between January 1, 2001, and August 31, 2007. Each child was investigated for the presence of Trypanosoma cruzi parasitemia through direct examination of blood under the microscope using the buffy coat method on three occasions during the first six months of life. Serological tests were then performed. Ninety-four children born to mothers infected with Trypanosoma cruzi were attended over the study period. Three of these children were born to mothers coinfected with the human immunodeficiency virus. Vertical transmission of Chagas disease was diagnosed in 13 children, in all cases by identifying parasitemia. The overall Chagas disease transmission rate was 13.8% (13/94). It was 100% (3/3) among the children born to mothers with HIV infection and 10.9% (10/91) among children born to mothers without HIV [Difference = 0.89; CI95 = 0.82-0.95; p = 0.0021]. We concluded that coinfection with HIV could increase the risk of vertical transmission of Chagas disease.

scholarly journals Corrigenda: Peixoto SR, Rocha DS, Dale C, Galvão C (2020) Panstrongylus geniculatus (Latreille, 1811) (Hemiptera, Reduviidae, Triatominae): first record on Ilha Grande, Rio de Janeiro, razil.Check List 16 (2): 391–394. https://doi.org/10.15560/16.2.391

Check List ◽  
2020 ◽  
Vol 16 (4) ◽  
pp. 989-989
Author(s):  
Solange Peixoto ◽  
Dayse da Silva Rocha ◽  
Carolina Dale ◽  
Cleber Galvão
Keyword(s):  
Trypanosoma Cruzi ◽  
Chagas Disease ◽  
Disease Transmission ◽  
Rio De Janeiro ◽  
New Record ◽  
First Record ◽  
First Report ◽  
Panstrongylus Geniculatus

Panstrongylus geniculatus (Latreille, 1811) is the most widely distributed species in Brazil. This study presents the first report of this species collected inside a building in the “Centro de Estudos Ambientais e Desenvolvimento Sustentável”, at the Vila Dois Rios, Ilha Grande, Rio de Janeiro, Brazil. The new record is important to understand the risk of Chagas disease transmission, mainly because this species is commonly found infected with Trypanosoma cruzi (Chagas, 1909).

scholarly journals Unraveling Chagas disease transmission through the oral route: Gateways to Trypanosoma cruzi infection and target tissues

2017 ◽  
Vol 11 (4) ◽  
pp. e0005507 ◽  
Author(s):  
Danielle Silva-dos-Santos ◽  
Juliana Barreto-de-Albuquerque ◽  
Bárbara Guerra ◽  
Otacilio C. Moreira ◽  
Luiz Ricardo Berbert ◽  
...  
Keyword(s):  
Trypanosoma Cruzi ◽  
Chagas Disease ◽  
Disease Transmission ◽  
Oral Route ◽  
Cruzi Infection

scholarly journals Trypanosoma cruzi-infected Rhodnius prolixus endure increased predation facilitating parasite transmission to mammal hosts

2021 ◽  
Vol 15 (7) ◽  
pp. e0009570
Author(s):  
Newmar Pinto Marliére ◽  
Marcelo Gustavo Lorenzo ◽  
Alessandra Aparecida Guarneri
Keyword(s):  
Trypanosoma Cruzi ◽  
Effective Means ◽  
Rhodnius Prolixus ◽  
Parasite Transmission ◽  
Intermediate Hosts ◽  
Oral Transmission ◽  
Vector Interaction ◽  
Triatomine Bugs ◽  
Increased Risk ◽  
Predation Rates

Triatomine bugs aggregate with conspecifics inside shelters during daylight hours. At dusk, they leave their refuges searching for hosts on which to blood feed. After finding a host, triatomines face the threat of being killed, because hosts often prey on them. As it is known that many parasites induce the predation of intermediate hosts to promote transmission, and that ingestion of Trypanosoma cruzi-infected bugs represents a very effective means for mammal infection, we hypothesized that trypanosomes induce infected bugs to take increased risk, and, as a consequence, be predated when approaching a host. Therefore, we evaluated whether the predation risk and predation rates endured by Rhodnius prolixus increase when infected with T. cruzi. Assays were performed in square glass arenas offering one central refuge to infected and uninfected 5th instar nymphs. A caged mouse was introduced in each arena after a three-day acclimation interval to activate sheltered insects and induce them to approach it. As hypothesized, a significantly higher proportion of infected insects was predated when compared with uninfected ones (36% and 19%, respectively). Indeed, T. cruzi-infected bugs took higher risk (Approximation Index = 0.642) when compared with healthy ones (Approximation Index = 0.302) and remained outside the shelters when the host was removed from the arena. Our results show that infection by T. cruzi induces bugs to assume higher risk and endure higher predation rates. We reveal a hitherto unknown trypanosome-vector interaction process that increases infected bug predation, promoting increased rates of robust oral transmission. The significant consequences of the mechanism revealed here make it a fundamental component for the resilient maintenance of sylvatic, peridomestic and domestic cycles.

scholarly journals Pigmentation loci as markers for genome editing in the Chagas disease vector Rhodnius prolixus

2020 ◽  
Author(s):  
M. Berni ◽  
D. Bressan ◽  
Y. Simão ◽  
A. Julio ◽  
P. L. Oliveira ◽  
...  
Keyword(s):  
Genome Editing ◽  
Chagas Disease ◽  
Rhodnius Prolixus ◽  
Disease Spread ◽  
Great Promise ◽  
Insect Vector ◽  
Alternative Strategies ◽  
Primary Model ◽  
Genes Encoding ◽  
Eye Pigmentation

AbstractThe kissing bug Rhodnius prolixus is a major vector for Chagas disease in the Americas, and also considered as the primary model for functional studies. Prospective transgenic approaches and genome editing strategies hold great promise for controlling insect populations as well as disease propagation. In this context, identifying visible genetic markers for transgenic methodologies is of paramount importance to advance the field. Here we have identified and analyzed the function of putative cuticle and eye color genes by investigating the effect of gene knockdown on fertility, viability, and the generation of visible phenotypes. Synthesis of the dark, yellow and tan pigments present in the cuticle of most insects depends on the function of key genes encoding enzymes in the tyrosine pathway. Knockdown of the R. prolixus yellow and aaNAT/pro orthologs produces striking alterations in cuticle color. Surprisingly, knockdown of ebony does not generate visible phenotypes. Since loss of ebony function results in a dark cuticle in several insect orders, we conclude that R. prolixus evolved alternative strategies for cuticle coloration, possibly including the loss of a pigmentation function for an entire branch of the tyrosine pathway. Knockdown of the scarlet and brown genes - encoding ABC transporters - alters cuticle and eye pigmentation, implying that the transport of pigment into proper organelles is an important process both for cuticle and eye coloration in this species. Therefore, this analysis identifies for the first time potential visible markers for transgenesis in a hemipteran vector for a debilitating human disease.Author SummaryThe hemipteran Rhodnius prolixus - also known as a kissing bug - is a main vector transmitting the parasite Trypanosoma cruzi, the causative agent of Chagas disease, a debilitating infection estimated to affect more than 6 million people in Central and South America. In order to limit disease spread, an important measure is insect vector control. However, kissing bugs - like other insects - develop resistance to insecticides. Alternative strategies based on transgenesis and the recently developed CRISPR- based genome edition hold great promise to control vector population or generate parasite-resistant insects. For these approaches to be feasible in R. prolixus, it is critical to identify visible phenotypic markers. Here we identify and describe several genes controlling cuticle and eye pigmentation that are well-suited putative landing sites for transformation strategies. Among these, loss-of-function mutations in the ABC transporter encoding scarlet and the tyrosine pathway enzyme encoding aaNAT/pro generate striking and easily visible phenotypes. Importantly, the knockdown of these genes does not affect insect viability and fertility under laboratory conditions. Our results suggest that R. prolixus has developed alternative strategies for cuticle coloration involving the loss of an entire branch of tanning loci, while the other branch producing cuticle patterns by generating non-pigmented areas has gained critical importance.

scholarly journals The mlpt/Ubr3/Svb module comprises an ancient developmental switch for embryonic patterning

eLife ◽  
2019 ◽  
Vol 8 ◽  
Author(s):  
Suparna Ray ◽  
Miriam I Rosenberg ◽  
Hélène Chanut-Delalande ◽  
Amélie Decaras ◽  
Barbara Schwertner ◽  
...  
Keyword(s):  
Molecular Complexes ◽  
Open Reading Frames ◽  
Epidermal Differentiation ◽  
Editorial Note ◽  
Embryonic Patterning ◽  
Embryo Patterning ◽  
Polished Rice ◽  
Developmental Switch ◽  
Small Open Reading Frames ◽  
Drosophila Embryos

Small open reading frames (smORFs) encoding ‘micropeptides’ exhibit remarkable evolutionary complexity. Conserved peptides encoded by mille-pattes (mlpt)/polished rice (pri)/tarsal less (tal) are essential for embryo segmentation in Tribolium but, in Drosophila, function in terminal epidermal differentiation and patterning of adult legs. Here, we show that a molecular complex identified in Drosophila epidermal differentiation, comprising Mlpt peptides, ubiquitin-ligase Ubr3 and transcription factor Shavenbaby (Svb), represents an ancient developmental module required for early insect embryo patterning. We find that loss of segmentation function for this module in flies evolved concomitantly with restriction of Svb expression in early Drosophila embryos. Consistent with this observation, artificially restoring early Svb expression in flies causes segmentation defects that depend on mlpt function, demonstrating enduring potency of an ancestral developmental switch despite evolving embryonic patterning modes. These results highlight the evolutionary plasticity of conserved molecular complexes under the constraints of essential genetic networks.Editorial note: This article has been through an editorial process in which the authors decide how to respond to the issues raised during peer review. The Reviewing Editor's assessment is that all the issues have been addressed (<xref ref-type="decision-letter" rid="SA1">see decision letter</xref>).

scholarly journals The control of Latin American trypanosomiasis

1997 ◽  
Vol 30 (6) ◽  
pp. 521-527 ◽  
Author(s):  
Philip D. Marsden
Keyword(s):  
Latin America ◽  
Trypanosoma Cruzi ◽  
Disease Control ◽  
Chagas Disease ◽  
Latin American ◽  
Present Situation ◽  
Point Of View ◽  
American Trypanosomiasis ◽  
Triatomine Bugs ◽  
Latin America Countries

The author presents his personal point of view on the present situation of Chagas' disease control in Latin America countries. He compares the situation with African trypanosomiasis. He comments on the existence of cases in other Continents. He emphazises the success of the fighting against domiciliated triatomine bugs by using residual inseticides. He discusses other forms of Trypanosoma cruzi transmission.

Sign in / Sign up

Export Citation Format

Share Document