Defective interfering particle
|This article needs additional citations for verification. (December 2009)|
Defective interfering particles (DIPs) are sub-viral entities that are sometimes found during a virus infection. During genome replication of a competent virus, sometimes defective genomes are generated that can still be packaged and form virus particles. However, the genome inside of such particles are not competent to replicate since they are missing part or most of their genetic information. Therefore, DIPs cannot sustain an infection by themselves. Instead, they depend on co-infection with a suitable helper virus, which can provide the gene functions that are absent from the DIPs.
The DIP interferes with the helper virus by competing for enzymes that the helper virus requires to multiply. Due to their smaller size, the genomes of the DIPs are more efficiently replicated than the full length viral genome, generating a very large number of non-infectious particles. DIPs have been shown to play a role in pathogenesis of certain viruses (such as Paramyxoviruses) in the fact that they attenuate some aspect of infection that would otherwise cause the host to be killed too rapidly. It is thought that the ability to generate defective genome during a replication has been selected by the evolution, since it increases the infection period and thereby, conferring the virus with more time to spread to new host cells.
1.Nayak, D. P., Chambers, T. M., & Akkina, R. K. (1985). Defective-Interfering (DI) RNAs of Influenza Viruses: Origin, Structure, Expression, and Interference. In M. Cooper, H. Eisen, W. Goebel, P. H. Hofschneider, H. Koprowski, F. Melchers, M. Oldstone, R. Rott, H. G. Schweiger, P. K. Vogt & I. Wilson (Eds.), Current Topics in Microbiology and Immunology (Vol. 114, pp. 103-151): Springer Berlin Heidelberg. 2. Philip I. Marcus,John M. Ngunjiri, and Margaret J. Sekellick. 2009. Dynamics of Biologically Active Subpopulations of Influenza Virus: Plaque-Forming, Noninfectious Cell-Killing, and Defective Interfering Particles. Journal of Virology 83:8122-8130
- Roux et al.,(1991), Adv Virus Res,40,181.
3.von Magnus, P. (1954). Incomplete Forms of Influenza Virus. In M. S. Kenneth & A. L. Max (Eds.), Advances in virus research (Vol. Volume 2, pp. 59-79): Academic Press. 4.Perrault, J. (1981). Origin and Replication of Defective Interfering Particles. In A. Shatkin (Ed.), Initiation Signals in Viral Gene Expression (Vol. 93, pp. 151-207): Springer Berlin Heidelberg. 5.Kristen A. Stauffer Thompson, Grzegorz A. Rempala, and John Yin. (2009). Multiple-hit inhibition of infection by defective interfering particles. J Gen Virol. 90(Pt 4): 888–899. doi: 10.1099/vir.0.005249-0, PMCID: PMC2889439