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A Comparative Study of Mayaro Virus TRVL and BeAr Strains
(Tartu Ülikool, 2025) Rutmane, Anna; Varjak, Margus, juhendaja; Merits, Andres, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Tehnoloogiainstituut
Mayaro virus (MAYV) is an arthritogenic alphavirus and the causative agent of Mayaro fever, which is characterized by myalgia, arthralgia, high fever, and maculopapular rash. Currently, the distribution of MAYV is limited to Central and South America, where it causes sporadic outbreaks. However, in recent years, there have been concerns about its potential emergence into urban transmission cycles. Phylogenetically, MAYV is divided into three distinct genotypes: D, L, and N. In this study, we investigate two MAYV strains: TRVL (genotype D) and BeAr (genotype L). To compare the replication and transcription efficiencies between the two strains, we implement a trans-replication system, in which the expression of alphavirus replicase and RNA replication are uncoupled. Our study indicates that the replicase of the TRVL strain is more active in human cells, whereas the replicase of the BeAr strain is more active in mosquito cells. The differences in replicase activity between the strains are driven by determinants located both within the replicase itself and within conserved sequence elements. Lastly, our experiments demonstrate that TRVL and BeAr strains are capable of co-infection.
Analysis of Chikungunya Virus Capsid Interactome
(Tartu Ülikool, 2024) Bratslavskaia, Elizaveta; Varjak, Margus, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Tehnoloogiainstituut
The ongoing global spread of alphaviruses presents a significant challenge, underscoring the urgent need for the development of novel antiviral treatments. Understanding the intricate host virus interactions that underlie virus infection is crucial for uncovering potential pro- or antiviral targets for such treatment strategies. In this study, we investigated the interactome of the Chikungunya virus (CHIKV) Capsid protein (CP), a key player in viral replication, assembly, and cell-virus interactions. Here, the quantitative label-free proteomics analysis was used to study CHIKV CP interactors in two different types of cells, in the human host and mosquito vector. A number of host and vector factors were identified, among them were many homologous proteins to be focused on in further downstream analysis. The effect of selected interactors on CHIKV pathogenesis was evaluated in mosquito and human cells. Notably, silencing of PGAM5, SRRT, and VIRMA proteins significantly reduced the level of viral replication, demonstrating a shared pro-viral effect in both, human and mosquito, cell types tested. These results underscore the conservation of CP function across different organisms and highlight the potential significance of these cellular factors in the context of CHIKV infection. Overall, this study provides valuable insights into the molecular mechanisms underlying CHIKV pathogenesis and identifies potential targets for the development of novel antiviral treatments.
Chikungunya viiruse mittestruktuurse valgu nsP3 ja raku valgu CD2AP vahelise interaktsiooni uurimine
(Tartu Ülikool, 2015-09-01) Tarve, Liisi; Merits, Andres, juhendaja; Varjak, Margus, juhendaja; Mutso, Margit, juhendaja; Tartu Ülikool. Loodus- ja tehnoloogiateaduskond; Tartu Ülikool. Molekulaar- ja rakubioloogia instituut