-
BMC Genomics Nov 2012Antibody responses against Anopheles salivary proteins can indicate individual exposure to bites of malaria vectors. The extent to which these salivary proteins are... (Comparative Study)
Comparative Study
BACKGROUND
Antibody responses against Anopheles salivary proteins can indicate individual exposure to bites of malaria vectors. The extent to which these salivary proteins are species-specific is not entirely resolved. Thus, a better knowledge of the diversity among salivary protein repertoires from various malaria vector species is necessary to select relevant genus-, subgenus- and/or species-specific salivary antigens. Such antigens could be used for quantitative (mosquito density) and qualitative (mosquito species) immunological evaluation of malaria vectors/host contact. In this study, salivary gland protein repertoires (sialomes) from several Anopheles species were compared using in silico analysis and proteomics. The antigenic diversity of salivary gland proteins among different Anopheles species was also examined.
RESULTS
In silico analysis of secreted salivary gland protein sequences retrieved from an NCBInr database of six Anopheles species belonging to the Cellia subgenus (An. gambiae, An. arabiensis, An. stephensi and An. funestus) and Nyssorhynchus subgenus (An. albimanus and An. darlingi) displayed a higher degree of similarity compared to salivary proteins from closely related Anopheles species. Additionally, computational hierarchical clustering allowed identification of genus-, subgenus- and species-specific salivary proteins. Proteomic and immunoblot analyses performed on salivary gland extracts from four Anopheles species (An. gambiae, An. arabiensis, An. stephensi and An. albimanus) indicated that heterogeneity of the salivary proteome and antigenic proteins was lower among closely related anopheline species and increased with phylogenetic distance.
CONCLUSION
This is the first report on the diversity of the salivary protein repertoire among species from the Anopheles genus at the protein level. This work demonstrates that a molecular diversity is exhibited among salivary proteins from closely related species despite their common pharmacological activities. The involvement of these proteins as antigenic candidates for genus-, subgenus- or species-specific immunological evaluation of individual exposure to Anopheles bites is discussed.
Topics: Animals; Anopheles; Base Sequence; Cluster Analysis; Computational Biology; Electrophoresis, Polyacrylamide Gel; Immunoblotting; Insect Vectors; Mass Spectrometry; Phylogeny; Proteome; Proteomics; Salivary Glands; Sequence Alignment; Species Specificity
PubMed: 23148599
DOI: 10.1186/1471-2164-13-614 -
Frontiers in Microbiology 2021Exposure of mosquitoes to numerous eukaryotic and prokaryotic microbes in their associated microbiomes has probably helped drive the evolution of the innate immune...
Exposure of mosquitoes to numerous eukaryotic and prokaryotic microbes in their associated microbiomes has probably helped drive the evolution of the innate immune system. To our knowledge, a metagenomic catalog of the eukaryotic microbiome has not been reported from any insect. Here we employ a novel approach to preferentially deplete host 18S ribosomal RNA gene amplicons to reveal the composition of the eukaryotic microbial communities of larvae sampled in Kenya, Burkina Faso and Republic of Guinea (Conakry). We identified 453 eukaryotic operational taxonomic units (OTUs) associated with larvae in nature, but an average of 45% of the 18S rRNA sequences clustered into OTUs that lacked a taxonomic assignment in the Silva database. Thus, the microbiome contains a striking proportion of novel eukaryotic taxa. Using sequence similarity matching and phylogenetic placement, the fraction of unassigned sequences was reduced to an average of 4%, and many unclassified OTUs were assigned as relatives of known taxa. A novel taxon of the genus in the phylum Apicomplexa (which also includes ) is widespread in larvae from East and West Africa. Notably, is present at fluctuating abundance among larval breeding sites, consistent with the expected pattern of an epidemic pathogen. Species richness of the eukaryotic microbiome was not significantly different across sites from East to West Africa, while species richness of the prokaryotic microbiome was significantly lower in West Africa. Laboratory colonies of harbor 26 eukaryotic OTUs, of which 38% ( = 10) are shared with wild populations, while 16 OTUs are unique to the laboratory colonies. Genetically distinct colonies co-housed in the same facility maintain different prokaryotic microbiome profiles, suggesting a persistent host genetic influence on microbiome composition. These results provide a foundation to understand the role of the eukaryotic microbiome in vector immunity and pathogen transmission. We hypothesize that prevalent apicomplexans such as associated with could induce interference or competition against within the vector. This and other members of the eukaryotic microbiome may offer candidates for new vector control tools.
PubMed: 34054746
DOI: 10.3389/fmicb.2021.635772 -
PLoS Pathogens Dec 2020Anopheles mosquitoes have transmitted Plasmodium parasites for millions of years, yet it remains unclear whether they suffer fitness costs to infection. Here we report...
Anopheles mosquitoes have transmitted Plasmodium parasites for millions of years, yet it remains unclear whether they suffer fitness costs to infection. Here we report that the fecundity of virgin and mated females of two important vectors-Anopheles gambiae and Anopheles stephensi-is not affected by infection with Plasmodium falciparum, demonstrating that these human malaria parasites do not inflict this reproductive cost on their natural mosquito hosts. Additionally, parasite development is not impacted by mating status. However, in field studies using different P. falciparum isolates in Anopheles coluzzii, we find that Mating-Induced Stimulator of Oogenesis (MISO), a female reproductive gene strongly induced after mating by the sexual transfer of the steroid hormone 20-hydroxyecdysone (20E), protects females from incurring fecundity costs to infection. MISO-silenced females produce fewer eggs as they become increasingly infected with P. falciparum, while parasite development is not impacted by this gene silencing. Interestingly, previous work had shown that sexual transfer of 20E has specifically evolved in Cellia species of the Anopheles genus, driving the co-adaptation of MISO. Our data therefore suggest that evolution of male-female sexual interactions may have promoted Anopheles tolerance to P. falciparum infection in the Cellia subgenus, which comprises the most important malaria vectors.
Topics: Animals; Anopheles; Ecdysterone; Female; Fertility; Gene Expression; Hormones; Host-Parasite Interactions; Malaria; Malaria, Falciparum; Male; Mosquito Vectors; Oogenesis; Plasmodium falciparum; Reproduction
PubMed: 33347501
DOI: 10.1371/journal.ppat.1008908 -
Journal of Virology Aug 2009Viruses in the genus Orthobunyavirus, family Bunyaviridae, have a genome comprising three segments (called L, M, and S) of negative-sense RNA. Serological studies have...
Viruses in the genus Orthobunyavirus, family Bunyaviridae, have a genome comprising three segments (called L, M, and S) of negative-sense RNA. Serological studies have classified the >170 named virus isolates into 18 serogroups, with a few additional as yet ungrouped viruses. Until now, molecular studies and full-length S-segment nucleotide sequences were available for representatives of eight serogroups; in all cases, the S segment encodes two proteins, N (nucleocapsid) and NSs (nonstructural), in overlapping open reading frames (ORFs) that are translated from the same mRNA. The NSs proteins of Bunyamwera virus (BUNV) and California serogroup viruses have been shown to play a role in inhibiting host cell mRNA and protein synthesis, thereby preventing induction of interferon (IFN). We have determined full-length sequences of the S segments of representative viruses in the Anopheles A, Anopheles B, and Tete serogroups, and we report here that these viruses do not show evidence of having an NSs ORF. In addition, these viruses have rather longer N proteins than those in the other serogroups. Most of the naturally occurring viruses that lack the NSs protein behaved like a recombinant BUNV with the NSs gene deleted in that they failed to prevent induction of IFN-beta mRNA. However, Tacaiuma virus (TCMV) in the Anopheles A serogroup inhibited IFN induction in a manner similar to that of wild-type BUNV, suggesting that TCMV has evolved an alternative mechanism, not involving a typical NSs protein, to antagonize the host innate immune response.
Topics: Animals; Anopheles; Bunyaviridae; Molecular Sequence Data; Open Reading Frames; Orthobunyavirus; Viral Nonstructural Proteins
PubMed: 19439468
DOI: 10.1128/JVI.02080-08 -
Annual Review of Entomology 1998Mosquitoes of the genus Anopheles transmit malaria parasites to humans. Anopheles mosquito species vary in their vector potential because of environmental conditions and... (Review)
Review
Mosquitoes of the genus Anopheles transmit malaria parasites to humans. Anopheles mosquito species vary in their vector potential because of environmental conditions and factors affecting their abundance, blood-feeding behavior, survival, and ability to support malaria parasite development. In the complex life cycle of the parasite in female mosquitoes, a process termed sporogony, mosquitoes acquire gametocyte-stage parasites from blood-feeding on an infected host. The parasites carry out fertilization in the midgut, transform to ookinetes, then oocysts, which produce sporozoites. Sporozoites invade the salivary glands and are transmitted when the mosquito feeds on another host. Most individual mosquitoes that ingest gametocytes do not support development to the sporozoite stage. Bottle-necks occur at every stage of the cycle in the mosquito. Powerful new techniques and approaches exist for evaluating malaria parasite development and for identifying mechanisms regulating malaria parasite-vector interactions. This review focuses on those interactions that are important for the development of new approaches for evaluating and blocking transmission in nature.
Topics: Animals; Anopheles; Host-Parasite Interactions; Humans; Insect Vectors; Malaria; Mosquito Control; Plasmodium
PubMed: 9444756
DOI: 10.1146/annurev.ento.43.1.519 -
Phytotherapy Research : PTR Feb 2018Medicinal plants have always had great value for the human population due to their valuable constituents and potential bioactivities. The objective of this review is to... (Review)
Review
Medicinal plants have always had great value for the human population due to their valuable constituents and potential bioactivities. The objective of this review is to present an updated overview of an important medicinal plant genus Nepeta L., from the family Lamiaceae, revealing its traditional utilization, biological activity, phytoconstituents, and mechanisms of action. For this purpose, a literature survey was carried out by using SciFinder, ScienceDirect, Scopus, PubMed, and Web of Science followed by a revision of the bibliographies of the related articles. We have described and analyzed the role of plants in drug discovery and the importance of Nepeta species. Information on the utilization purposes of Nepeta species in folk medicine has been emphasized, and scientific studies on the biological effects and secondary metabolites are addressed. Nepeta species are characterized by terpenoid-type compounds and phenolic constituents, which exert several activities such as an antimicrobial, repellent against major pathogen vector mosquitoes, insecticide, larvicide against Anopheles stephensi, cytotoxic anticarcinogen, antioxidant, anticonvulsant, analgesic, anti-inflammatory agent, and antidepressant, revealing its importance in medicinal and agricultural fields. On the basis of numerous studies, the Nepeta genus demonstrates remarkable therapeutic effects against various diseases. However, clinical studies are warranted to confirm preclinical findings.
Topics: Humans; Medicine, Traditional; Nepeta; Phytotherapy; Plants, Medicinal
PubMed: 29044858
DOI: 10.1002/ptr.5946 -
Infection, Genetics and Evolution :... Jun 2022Anopheles is a genus belonging to the Culicidae family, which has great medical importance due to its role as a vector of Plasmodium, the causative agent of malaria.... (Review)
Review
Anopheles is a genus belonging to the Culicidae family, which has great medical importance due to its role as a vector of Plasmodium, the causative agent of malaria. Great focus has been given to the salivary gland proteins (SGPs) group from Anopheles' functional genomics. This class of proteins is essential to blood-feeding behavior as they have attributes such as vasodilators and anti-clotting properties. Recently, a comprehensive review on Anopheles SGPs was performed; however, the authors did not deeply explore the adaptive molecular evolution of these genes. In this context, this work aimed to perform a more detailed analysis of the adaptive molecular evolution of SGPs in Anopheles, carrying out positive selection and gene family evolution analysis on 824 SGPs. Our results show that most SGPs have positively selected codon sites that can be used as targets in developing new strategies for vector control and that younger SGPs evolve at a faster rate than older SGPs. Notably, we could not find any evidence of an accelerated shift in SGPs' rates of gene gain and loss compared with other proteins, as suggested in previous works.
Topics: Animals; Anopheles; Evolution, Molecular; Insect Proteins; Malaria; Mosquito Vectors; Salivary Proteins and Peptides
PubMed: 35339698
DOI: 10.1016/j.meegid.2022.105271 -
Royal Society Open Science Nov 2017Malaria is a vector-borne disease that is a great burden on the poorest and most marginalized communities of the tropical and subtropical world. Approximately 41 species...
Malaria is a vector-borne disease that is a great burden on the poorest and most marginalized communities of the tropical and subtropical world. Approximately 41 species of Anopheline mosquitoes can effectively spread species of parasites that cause human malaria. Proposing a natural classification for the subfamily Anophelinae has been a continuous effort, addressed using both morphology and DNA sequence data. The monophyly of the genus , and phylogenetic placement of the genus , subgenera , and within the subfamily Anophelinae, remain in question. To understand the classification of Anophelinae, we inferred the phylogeny of all three genera (, , ) and major subgenera by analysing the amino acid sequences of the 13 protein coding genes of 150 newly sequenced mitochondrial genomes of Anophelinae and 18 newly sequenced species as outgroup taxa, supplemented with 23 mitogenomes from GenBank. Our analyses generally place genus within the genus , which implies that the latter as it is currently defined is not monophyletic. With some inconsistencies, was placed within the major clade that includes , , , , and , which were found to be monophyletic groups within Anophelinae. Our findings provided robust evidence for elevating the monophyletic groupings , , and to genus level; genus to include subgenera , , and ; to be placed into a new genus; to be elevated to genus level; the genus to include subgenera and ; and to be transferred from subgenus to subgenus ; and subgenus to encompass the remaining species of Argyritarsis and Albimanus Sections.
PubMed: 29291068
DOI: 10.1098/rsos.170758 -
Advances in Experimental Medicine and... 2008Symbiotic bacteria have been proposed as tools for control of insect-borne diseases. Primary requirements for such symbionts are dominance, prevalence and stability... (Review)
Review
Symbiotic bacteria have been proposed as tools for control of insect-borne diseases. Primary requirements for such symbionts are dominance, prevalence and stability within the insect body. Most of the bacterial symbionts described to date in Anopheles mosquitoes, the vector of malaria in humans, have lacked these features. We describe an alpha-Proteobacterium of the genus Asaia, which stably associates with several Anopheles species and dominates within the body of An. stephensi. Asaia exhibits all the required ecological characteristics making it the best candidate, available to date, for the development ofa paratransgenic approach for manipulation of mosquito vector competence. Key features of Asaia are: (i) dominance within the mosquito-associated microflora, as shown by clone prevalence in 16S rRNA gene libraries and quantitative real time Polymerase Chain Reaction (qRT-PCR); (ii) cultivability in cell-free media; (iii) ease of transformation with foreign DNA and iv) wide distribution in the larvae and adult mosquito body, as revealed by transmission electron microscopy, and in situ-hybridization experiments. Using a green fluorescent protein (GFP)-tagged Asaia strain, it has been possible to show that it effectively colonizes all mosquito body organs necessary for malaria parasite development and transmission, including female gut and salivary glands. Asaia was also found to massively colonize the larval gut and the male reproductive system of adult mosquitoes. Moreover, mating experiments showed an additional key feature necessary for symbiotic control, the high transmission potential of the symbiont to progeny by multiple mechanisms. Asaia is capable of horizontal infection through an oral route during feeding both in preadult and adult stages and through a venereal pattern during mating in adults. Furthermore, Asaia is vertically transmitted from mother to progeny indicating that it could quickly spread in natural mosquito populations.
Topics: Animals; Anopheles; Humans; Malaria; Proteobacteria; Symbiosis; Transgenes
PubMed: 18510013
DOI: 10.1007/978-0-387-78225-6_4 -
Bulletin of Entomological Research Dec 2004The internal classification of genus Anopheles is updated to reflect taxonomic actions published since the classification was last reviewed in 1994. Both formal and... (Comparative Study)
Comparative Study
The internal classification of genus Anopheles is updated to reflect taxonomic actions published since the classification was last reviewed in 1994. Both formal and informal taxa are included. The classification is intended to aid researchers and students who are interested in analysing species relationships, making group comparisons and testing phylogenetic hypotheses. The genus includes 444 formally named and 40 provisionally designated extant species divided between six subgenera: Anopheles, Cellia, Kerteszia, Lophopodomyia, Nyssorhynchus and Stethomyia. Subgenera Anopheles, Cellia and Nyssorhynchus are subdivided hierarchically into nested informal groups of morphologically similar species that are believed to represent monophyletic lineages based on morphological similarity. Changes to the classification include additional species, eliminated species and changes to the hierarchical organization and composition of supraspecific groups, some as a result of molecular studies.
Topics: Animals; Anopheles; Phylogeny; Species Specificity
PubMed: 15541193
DOI: 10.1079/ber2004321