Bunyaviridae nonstructural S proteins (NSs) are synthesized by viral DNA/RNA and do not play a role in the replication or the viral protein coating.[1] The nonstructural S segment (NSs) created by Bunyaviridae virus family, are able to interact with the human immune system, in order to increase their replication in infected cells.[2] Understanding this mechanism can have global health impacts.[3]
Inhibition Pathways
editWithin the Bunyaviridae virus family, specifically phlebovirus genus, there has been multiple pathways of the inhibition of the immune response.[3] NSs proteins are able to interact with interferon (INF) pathways, but the mechanism varies from virus to virus.[4] The NSs protein in different viruses have been shown to differ in amino acid sequence by up to 85%.[5]
Rift Valley Fever Virus (RVFV)
editNSs protein is distributed throughout the cytoplasm and nucleus of the infected cell. The protein created fiber-like substances within the nucleus.[3] NSs in RVFV to the SAP30 region of DNA in the nucleus of the cell, which is an important promotor region of INF-b.[6] Many other NSs proteins in the Bunyaviridae virus family do not function in this same way.[5]
Although the exact target of the SFTSV is unknown, many believe that the virus attacks human hemopoietic cells.[7] It has been shown that upstream molecules of INFs are unchanged in infected cells, such as MAVS, TRAF6 and TRAF3.[7] This suggests that INFs are still being produced, but they have no effect and are undetectable in people's blood serum.[6] The NSs protein in SFTSV has been shown to interfere with TBK1 which is needed in the activation of both IRF and NF-κB pathways.[7]
Uukuniemi virus (UUKV)
editUUKV is a non-human pathogen that still creates a NSs protein.[5] The NSs protein has only been shown to weakly interact with the 40s subunit of ribosomes and MAVS.[8][9][10]
Arumowot virus (AMTV)
editAMTV is another non-human pathogen and its NSs protein is quickly degraded by proteasomes, and therefor doesn't cause infection in humans.[11]
References
edit- ^ Viral+Nonstructural+Proteins at the U.S. National Library of Medicine Medical Subject Headings (MeSH)
- ^ ZHANG, S.; ZHENG, B.; WANG, T.; LI, A.; WAN, J.; QU, J.; LI, CH.; LI, D.; LIANG, M. (2017). "NSs protein of severe fever with thrombocytopenia syndrome virus suppresses interferon production through different mechanism than Rift Valley fever virus". Acta Virologica. 61 (3): 289–298. doi:10.4149/av_2017_307. ISSN 1336-2305. PMID 28854793.
- ^ a b c Wu, Xiaodong; Qi, Xian; Liang, Mifang; Li, Chuan; Cardona, Carol J.; Li, Dexin; Xing, Zheng (2014). "Roles of viroplasm-like structures formed by nonstructural protein NSs in infection with severe fever with thrombocytopenia syndrome virus". The FASEB Journal. 28 (6): 2504–2516. doi:10.1096/fj.13-243857. ISSN 1530-6860. PMID 24599967. S2CID 20158858.
- ^ Chaudhary, Vidyanath; Zhang, Shuo; Yuen, Kit-San; Li, Chuan; Lui, Pak-Yin; Fung, Sin-Yee; Wang, Pei-Hui; Chan, Chi-Ping; Li, Dexin; Kok, Kin-Hang; Liang, Mifang (2015). "Suppression of type I and type III IFN signalling by NSs protein of severe fever with thrombocytopenia syndrome virus through inhibition of STAT1 phosphorylation and activation". Journal of General Virology. 96 (11): 3204–3211. doi:10.1099/jgv.0.000280. hdl:10722/216602. ISSN 1465-2099. PMID 26353965.
- ^ a b c Leventhal, Shanna S.; Wilson, Drew; Feldmann, Heinz; Hawman, David W. (February 2021). "A Look into Bunyavirales Genomes: Functions of Non-Structural (NS) Proteins". Viruses. 13 (2): 314. doi:10.3390/v13020314. PMC 7922539. PMID 33670641.
- ^ a b May, Nicolas Le; Mansuroglu, Zeyni; Léger, Psylvia; Josse, Thibaut; Blot, Guillaume; Billecocq, Agnès; Flick, Ramon; Jacob, Yves; Bonnefoy, Eliette; Bouloy, Michèle (2008-01-25). "A SAP30 Complex Inhibits IFN-β Expression in Rift Valley Fever Virus Infected Cells". PLOS Pathogens. 4 (1): e13. doi:10.1371/journal.ppat.0040013. ISSN 1553-7374. PMC 2323286. PMID 18225953.
- ^ a b c Qu, Bingqian; Qi, Xian; Wu, Xiaodong; Liang, Mifang; Li, Chuan; Cardona, Carol J.; Xu, Wayne; Tang, Fenyang; Li, Zhifeng; Wu, Bing; Powell, Kira (2012-08-15). "Suppression of the Interferon and NF-κB Responses by Severe Fever with Thrombocytopenia Syndrome Virus". Journal of Virology. 86 (16): 8388–8401. doi:10.1128/JVI.00612-12. PMC 3421730. PMID 22623799.
- ^ Rezelj, Veronica V.; Överby, Anna K.; Elliott, Richard M. (2015). "Generation of Mutant Uukuniemi Viruses Lacking the Nonstructural Protein NSs by Reverse Genetics Indicates that NSs Is a Weak Interferon Antagonist". Journal of Virology. 89 (9): 4849–4856. doi:10.1128/JVI.03511-14. PMC 4403475. PMID 25673721.
- ^ Simons, J F; Persson, R; Pettersson, R F (1992-07-01). "Association of the nonstructural protein NSs of Uukuniemi virus with the 40S ribosomal subunit". Journal of Virology. 66 (7): 4233–4241. doi:10.1128/jvi.66.7.4233-4241.1992. PMC 241227. PMID 1534850.
- ^ Rezelj, Veronica V.; Li, Ping; Chaudhary, Vidyanath; Elliott, Richard M.; Jin, Dong-Yan; Brennan, Benjamin (2017). "Differential Antagonism of Human Innate Immune Responses by Tick-Borne Phlebovirus Nonstructural Proteins". mSphere. 2 (3): e00234–17. doi:10.1128/mSphere.00234-17. PMC 5489658. PMID 28680969.
- ^ Hallam, Hoai J.; Lokugamage, Nandadeva; Ikegami, Tetsuro (2019-11-21). "Rescue of infectious Arumowot virus from cloned cDNA: Posttranslational degradation of Arumowot virus NSs protein in human cells". PLOS Neglected Tropical Diseases. 13 (11): e0007904. doi:10.1371/journal.pntd.0007904. ISSN 1935-2735. PMC 6894884. PMID 31751340.