NSP1 (rotavirus)

From Wikipedia, the free encyclopedia

NSP1, the product of rotavirus gene 5, is an nonstructural RNA-binding protein that contains a cysteine-rich region and is a component of early replication intermediates. RNA-folding predictions suggest that this region of the NSP1 mRNA can interact with itself, producing a stem-loop structure similar to that found near the 5'-terminus of the NSP1 mRNA.[1]

The carboxyl-half of the rotavirus nonstructural protein NSP1 is not required for virus replication.[2]

NSP1 could play a role in host range restriction.[3]

The cysteine-rich region of NSP1 is not considered essential for genome segment reassortment with heterologous virus.[4]

NSP1, interacts with IRF3 in the infected cell. NSP1 is an antagonist of the IFN-signaling pathway.[5]

Interferon regulatory factor 3 (IRF3) is a key transcription factor involved in the induction of interferon (IFN) in response to viral infection. NSP1 binds to and targets IRF3 for proteasome degradation early post-infection. IRF3 degradation is dependent on the presence of NSP1 and the integrity of the N-terminal zinc-binding domain, coupled with the regulated stability of IRF3 and NSP1 by the proteasome, collectively support the hypothesis that NSP1 is an E3 ubiquitin ligase.[6]

NSP1 could mediates the degradation of IRF3, IRF5, and IRF7 by recognizing a common element of IRF proteins, thereby allowing NSP1 to act as a broad-spectrum antagonist of IRF function.[7]

[edit] References

  1. ^ Hua, J; E A Mansell, J T Patton (1993- Sep). "Comparative analysis of the rotavirus NS53 gene: conservation of basic and cysteine-rich regions in the protein and possible stem-loop structures in the RNA.". Virology 196 (1): 372–8. doi:10.1006/viro.1993.1492. 8395125 doi:10.1006/viro.1993.1492. 
  2. ^ Hua, J; J T Patton (1994- Feb). "The carboxyl-half of the rotavirus nonstructural protein NS53 (NSP1) is not required for virus replication.". Virology 198 (2): 567–76. doi:10.1006/viro.1994.1068. 8291239 doi:10.1006/viro.1994.1068. 
  3. ^ Dunn, S J; T L Cross, H B Greenberg (1994- Aug- 15). "Comparison of the rotavirus nonstructural protein NSP1 (NS53) from different species by sequence analysis and northern blot hybridization.". Virology 203 (1): 178–83. doi:10.1006/viro.1994.1471. 8030275 doi:10.1006/viro.1994.1471. 
  4. ^ Okada, J; N Kobayashi, K Taniguchi, S Urasawa (1999). "Analysis on reassortment of rotavirus NSP1 genes lacking coding region for cysteine-rich zinc finger motif.". Archives of virology 144 (2): 345–53. doi:10.1007/s007050050508. 10470258. 
  5. ^ Barro, Mario; John T Patton (2005- Mar- 15). "Rotavirus nonstructural protein 1 subverts innate immune response by inducing degradation of IFN regulatory factor 3.". Proceedings of the National Academy of Sciences of the United States of America 102 (11): 4114–9. doi:10.1073/pnas.0408376102. 15741273 doi:10.1073/pnas.0408376102. 
  6. ^ Graff, Joel W; Julie Ewen, Khalil Ettayebi, Michele E Hardy (2007- Feb). "Zinc-binding domain of rotavirus NSP1 is required for proteasome-dependent degradation of IRF3 and autoregulatory NSP1 stability.". The Journal of general virology 88 (Pt 2): 613–20. doi:10.1099/vir.0.82255-0. 17251580 doi:10.1099/vir.0.82255-0. 
  7. ^ Barro, Mario; John T Patton (2007- May). "Rotavirus NSP1 inhibits expression of type I interferon by antagonizing the function of interferon regulatory factors IRF3, IRF5, and IRF7.". Journal of virology 81 (9): 4473–81. doi:10.1128/JVI.02498-06. 17301153 doi:10.1128/JVI.02498-06.