Difference between revisions of "Part:BBa K3504015"

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nSP3'-Semliki forest virus

Part Description

Nsp3 is one of four non structural proteins that together forms the main complex responsible for the synthesis positive-sense viral RNAs, results in the synthesis of both the genomic and subgenomic RNAs, of which the subgenomic RNA is produced in excess of the viral genome. Which allows the virus to self-replicate into millions of copies of the virus.

Usage

∼60kDa nsP3 : The functional role of the nsP3 hasn’t been clear throughout history. It still has a primary part in the RNA synthesis as mutations in nsP3 exhibited defects in the start of minus-strand synthesis or subgenomic RNA synthesis. The alphavirus nsP3 protein has three recognized domains: the macrodomain, the alphavirus unique domain (AUD) and the hypervariable region. The macrodomains of CHIKV and VEEV were found to bind to DNA, RNA and polyADP-ribose in addition to exhibiting adenosine diphosphoribose 1′-phosphate phosphatase activity. Genetic manipulations within the AUD have resulted in defects in minus-strand and subgenomic RNA synthesis, polyprotein processing, and neurovirulence where the exact mechanism is not identified up till now. The C-terminal domain of nsP3 is characterized as being hypervariable and this hypervariable domain is shown to be responsible for the formation of virus-species specific complexes in infected cells. At this time it is not clear that the identified interactions of nsP3 with host factors influence viral RNA synthesis or whether they are indicative of another nsP3 function that regulates the host cell environment.

Characterization

We have made simulations using mathematical modelling techniques to characterize the increase in expression when using replicons over traditional methods while also providing simulations that Characterize the function of replicon by eliciting an increased response in both Dendritic Cell population and T-Helper Population.

We also provide Functional characterization of replicons from literature. As This figure shows HIVA-specific T-cell responses after a single immunization with clinical-grade plasmid DNA vaccines between DREP.HIVA and pTHr.HIVA in individual mice immunized by 10 μg of them all of which complies with our mathematical modelling & simulations

Figure 1. Functional characterization of replicons from literature. This figure shows HIVA-specific T-cell responses after a single immunization with clinical-grade plasmid DNA vaccines between DREP.HIVA and pTHr.HIVA in individual mice immunized by 10 μg of them.

Figure 2. Mathematical modelling simulation of Number of positive strand RNA in traditional vaccination presented by the graph to the left vs with the use of self amplifying replicon on the right.

Figure 3. Mathematical modelling simulation of T-helper cells population response according to logfc in response to DREP vaccine on the left vs traditional DNA vaccine on the right.

Figure 4. Mathematical modelling simulation of Dendritic Cells population response according to logfc in response to DREP vaccine on the left vs traditional DNA vaccine on the right.

References

Li, Y., Teague, B., Zhang, Y., Su, Z., Porter, E., Dobosh, B., ... & Weiss, R. (2019). In vitro evolution of enhanced RNA replicons for immunotherapy. Scientific reports, 9(1), 1-10.

Nordström, E. K., Forsell, M. N., Barnfield, C., Bonin, E., Hanke, T., Sundström, M., ... & Liljeström, P. (2005). Enhanced immunogenicity using an alphavirus replicon DNA vaccine against human immunodeficiency virus type 1. Journal of general virology, 86(2), 349-354. Sequence and Features