Usuari:Sajolida/proves2
Patogènesi
[modifica]Tot i que molts components de la RNA de la FVR tener un paper important en la patologia del virus, la proteïna noestructural codificada en el segment S (NSs) és l'únic component que s'ha trobat que afecta directament l'hoste. NSs és hostil i combativa contra els hosts interferon (IFNs) antiviral response.[1] IFNs are essential in order for the immune system to fight off viral infections in a host.[2] This inhibitory mechanism is believed to be due to a number of reasons, the first being, competitive inhibition of the formation of the transcription factor.[1] On this transcription factor, NSs interacts with and binds to a subunit that is needed for RNA polymerase I and II.[1][3] This interaction cause competitive inhibition with another transcription factor component and prevents the assembly process of the transcription factor complex, which results in the suppression of the host antiviral response.[1][3] Transcription suppression is believed to be another mechanism of this inhibitory process.[1] This occurs when an area of NSs interacts with and binds to the host’s protein, SAP30 and forms a complex.[1][3] This complex causes histone acetylation to regress, which is needed for transcriptional activation of the IFN promoter.[3] This causes IFN expression to be obstructed. Lastly, NSs has also been known to affect regular activity of double-stranded RNA-dependent protein kinase R.. This protein is involved in cellular antiviral responses in the host. When RVFV is able to enter the hosts DNA, NSs forms a filamentous structure in the nucleus. This allows the virus to interact with specific areas of the hosts DNA that relates to segregation defects and induction of chromosome continuity. This increases host infectivity and decreases the host’s antiviral response.[1]
- ↑ 1,0 1,1 1,2 1,3 1,4 1,5 1,6 Boshra, Hani; Lorenzo, Gema; Busquets, Núria; Brun, Alejandro «Rift Valley Fever: Recent Insights into Pathogenesis and Prevention» (en anglès). Journal of Virology, vol. 85, 13, 01-07-2011, pàg. 6098–6105. DOI: 10.1128/JVI.02641-10. ISSN: 0022-538X. PMC: 3126526. PMID: 21450816.
- ↑ Fensterl, Volker; Sen, Ganes C. «Interferons and viral infections» (en anglès). BioFactors, vol. 35, 1, 01-01-2009, pàg. 14–20. DOI: 10.1002/biof.6. ISSN: 1872-8081. PMID: 19319841.
- ↑ 3,0 3,1 3,2 3,3 Ikegami, Tetsuro; Makino, Shinji «The Pathogenesis of Rift Valley Fever». Viruses, vol. 3, 5, 06-05-2011, pàg. 493–519. DOI: 10.3390/v3050493. ISSN: 1999-4915. PMC: 3111045. PMID: 21666766.