Search bioRxiv⌕ Search

bioRxiv · 10.1101/2025.06.20.660662

Serotypes of Dengue Virus and Kdr Mutations F1534C, S989P, V410L, V1016I, and V1016G in Aedes aegypti and Aedes albopictus Mosquitoes from the commune of AbomeyCalavi, Southern Benin

Abstract

Dengue is a viral infection transmitted by mosquitoes of the Aedes genus, responsible for millions of cases each year. In Benin, several outbreaks have been reported, particularly in Abomey-Calavi, where the first dengue-related death was recorded in 2019. In the absence of a specific treatment, vector control remains the primary preventive measure. However, the emergence of insecticide resistance, notably through kdr mutations, could compromise its effectiveness. This study aims to identify the dengue virus serotypes circulating in the commune of Abomey-Calavi and to assess the frequency of kdr mutations V410L, V1016G, V1016I, F1534C, and S989P in Aedes aegypti and Aedes albopictus mosquitoes. Mosquitoes were collected in August 2024 from four arrondissement Togba, Calavi, Akassato, and Godomey through morning and afternoon spraying. After morphological identification, molecular analyses were conducted to detect the viral serotypes and kdr mutations. A total of 218 Aedes mosquitoes were collected, with a predominance of Aedes aegypti (68.8%) compared to Aedes albopictus (31.2%). The overall dengue positivity rate was 23.39% (95% CI: 17.9 - 29.6). The most frequent serotype was DENV-3 (12.4%), followed by DENV-2 (6.9%), DENV-1 (5%), and DENV-4 (0.09%). Six mosquitoes were co-infected with two serotypes, including three with DENV-1 and DENV-4. kdr mutations were detected in both species, with frequencies of 45% for V1016G, 44% for S989P, 40% for F1534C, 22% for V410L, and 19% for V1016I. Four mosquitoes carried three simultaneous mutations, while twenty-two carried two. Two mosquitoes co-infected with two serotypes also carried two different mutations. These results highlight the active circulation of the dengue virus and the presence of kdr mutations in Aedes mosquitoes in Abomey-Calavi. However, no significant association was observed between dengue infection and kdr mutations, and their distribution was independent of the viral serotype. These findings emphasize the need for regular monitoring of kdr mutations to adapt vector control strategies and limit the spread of dengue.

Source connections

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Tokponnon, F. T., AMOUSSA, O. D. A., Dabou, Z. S., Kpemasse, N., Ahouandjinou, M. J., Towakinou, L., Agassounon, B., Tandjekpon, O. S., Gandaho, F. C., Issa, M., Gounou Yerima, I., Houessinon, F., Dougnon, V., Oxborough, R. M., Mesenger, L., Osse, R., Baba-Moussa, L., KINDE-GAZARD, D., Akogbeto, M.. 2025-06-24. Serotypes of Dengue Virus and Kdr Mutations F1534C, S989P, V410L, V1016I, and V1016G in Aedes aegypti and Aedes albopictus Mosquitoes from the commune of AbomeyCalavi, Southern Benin. https://doi.org/10.1101/2025.06.20.660662

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related preprints

Protoribosomal condensate formation across cationic chemistries

Early ribonucleoprotein systems likely required mechanisms to concentrate and organize RNA. Modern ribosomes use Mg2+ and evolved Lys/Arg-rich protein extensions to stabilize their RNA backbone. Before templated synthesis, however, peptide formation likely generated heterogeneous sequence populations rather than reproducible ribosomal sequences. Here, we compare Mg2+, ribosomal peptides, and statistical peptide libraries in organizing a 136-nucleotide model of the peptidyl transferase center (sPTC). Mg2+ condenses sPTC only at a large excess of positive charge following thermal annealing, producing largely arrested libraries. Acidic conditions further promote condensation. Ribosomal peptides instead promote coacervation near charge stoichiometry and form droplets that readily fuse. Several statistical peptide libraries also coacervate with sPTC, despite comprising heterogenous mixtures rather than a single defined sequence. Increasing mean positive charge favors condensation, but Lys/Arg-containing libraries undergo liquid-liquid phase separation more readily and across broader conditions than matched libraries containing the prebiotically plausible diaminopropionic acid (Dpr) and diaminobutyric acid (Dab). Atomistic computer simulations implicate Arg as a major source of this difference, as it can form more numerous and longer-lived hydrogen bonds with RNA, while competitive partitioning experiments show preferential condensate recruitment in the order Arg > Lys > Dab > Dpr. Together, our findings show that peptide-RNA coacervation can be triggered collectively by statistical peptide ensembles, providing a plausible route to protoribosomal organization without peptide sequence-specific optimization. Cationic chemistry shapes condensate formation and material properties, suggesting that amino acid alphabet formation could have broadened the conditions supporting liquid-like protoribosomal assemblies.

biochemistry↗

A scalable recombinant pipeline for disulphide-stapled peptides

Constrained macrocyclic peptides can engage protein surfaces that resist both small molecules and biologics but producing them at library scale still depends on chemical synthesis and macrocyclisation workflows that are slow, specialised and hard to parallelise. We describe a recombinant pipeline for disulphide-stapled cyclic peptides, compatible with 96 well plates, that lowers this barrier. Peptide-encoding sequences are introduced by extension PCR and in vivo assembly (IVA) cloning at about $2 per variant, expressed as small ubiquitin-like modifier (SUMO) fusions secreted to the oxidising periplasm, where the intramolecular disulphide forms spontaneously, and purified by immobilised metal-affinity chromatography (IMAC) with analytical size-exclusion chromatography (SEC). The route from a list of designs to characterised material takes about one week, much of it unattended. Applied to a 60-design library across nine protein targets, the pipeline gave purified products for all 60 designs, at a median total soluble yield of approximately 135 micrograms per 6 mL culture (range 9 to 261) that varied by target. Ellman's assay across 38 designs showed disulphide-formation failure to be sequence-driven and uncorrelated with yield, detecting a failure mode invisible to chromatography. Surface plasmon resonance confirmed target binding and showed that the recombinant SUMO fusion constructs retained affinities comparable to their corresponding peptide-only forms. Complementary to general-purpose recombinant platforms, the pipeline enables higher-throughput disulphide macrocycle screening and is amenable to partially or fully automated workflows.

biochemistry↗

Programmable sequence-resolved in situ profiling of glycoRNA-protein interactomes by GlycoRNA-Map

Cell-surface glycoRNAs participate in diverse biological processes, but they were investigated as pooled populations and the protein interactome of individual glycoRNA species remain unresolved. Here we develop GlycoRNA-Map, a programmable photocatalytic proximity-labeling method that maps proteins surrounding sequence-defined endogenous glycoRNAs on living cells. A sialic-acid-binding aptamer and an RNA-hybridization probe jointly recruit a fluorophore-modified oligonucleotide through dual recognition of the glycan and RNA moieties of glycoRNAs. Light-activated biotinylation followed by quantitative mass spectrometry identified 200-418 enriched proteins for each of five glycoRNAs in A549 cells. Comparison of these proteomes revealed limited overlap among different glycoRNA sequences and across cell types, demonstrating that glycoRNA-associated protein environments depend on both RNA identity and cellular context. Transforming growth factor-{beta} receptors 1 and 2 (TGFBR1 and TGFBR2) were identified in the proximal proteomes of multiple glycoRNAs. Removal of cell-surface RNAs enhanced TGF-{beta} receptor signaling and promoted cell migration, demonstrating that glycoRNAs can functionally regulate extracellular signaling by interacting with their protein neighborhoods. GlycoRNA-Map thus provides an accessible strategy for resolving sequence-specific glycoRNA-protein interactome and discovering their roles in membrane signaling.

biochemistry↗