This post is a review of the paper discussed by Lee Hutt and myself in Friday’s seminar.
Poxviruses are considered to be unique because of their ability to replicate only in the cytoplasm of their host cell, outside of the nucleus. This paper explores this strategy and its discovered use within the Acanthamoeba infecting Mimivirus. As has been previously discussed in posts by Lee and myself, the Mimivirus is one of the largest and most complex viruses, boasting a 1.2Mb genome. The knowledge of this virus is ever adapting and evolving as new techniques are implemented, with most recent being the rise in known gene number from 917 to 1018. The Mimivirus has raised a lot of debate and questioning concerning the relationship between viruses and single celled organisms. Most of this interest has spiked from the discovery of the virus possessing genes for nucleotide and amino acid synthesis. The virus is as large as several bacteria, has a bigger genome than many and contains genetic information that was previously unknown and thought not possible for viruses. This paper and many recent others generally highlight the underestimation of the ability of viruses.
This paper explores the evolution of the Mimivirus to perform cytoplasmic replication. Since the nucleus provides an optimal, ready-made site for viral replication, the use of the cytoplasm for this function is extremely unusual and maybe even unnecessary. However, the Mimivirus has turned to building large and elaborate replication ‘factories’ within the cytoplasm of its host,
operating seemingly independently. This brings into question our current understanding of the infection strategies of other large DNA viruses of the NCLDV clade. Some works have suggested that this may be made possible by ‘leakage’ of nuclear enzymes. This has been proven for replication of the Vaccinia virus, however this is not yet the case for the Mimivirus.
This paper also applies methods which we have recently been familiarised with such as fluorescent in situ hybridisation, immunofluorescence and general image processing and microscopy. New techniques have allowed researchers to thoroughly investigate the infection cycle of the Mimivirus, presenting the previously mentioned independent replication ‘factories’.
This paper is of great importance in furthering research and knowledge of the Mimivirus. It shows how current techniques can be applied to explore infection strategies, highlights the evolution of the Mimivirus and its relatives, and also opens up a wide range of questions concerning our basic knowledge of viruses, their current status, their evolution and their future.
A review of:
Mutsafi, Y., Zauberman, N., Sabanay, I. and Minsky, A., 2010. Vaccinia-like cytoplasmic replication of the giant Mimivirus. Proc. Natl. Acad. Sci. U. S. A, 107, pp. 5978-5982.
Poxviruses are considered to be unique because of their ability to replicate only in the cytoplasm of their host cell, outside of the nucleus. This paper explores this strategy and its discovered use within the Acanthamoeba infecting Mimivirus. As has been previously discussed in posts by Lee and myself, the Mimivirus is one of the largest and most complex viruses, boasting a 1.2Mb genome. The knowledge of this virus is ever adapting and evolving as new techniques are implemented, with most recent being the rise in known gene number from 917 to 1018. The Mimivirus has raised a lot of debate and questioning concerning the relationship between viruses and single celled organisms. Most of this interest has spiked from the discovery of the virus possessing genes for nucleotide and amino acid synthesis. The virus is as large as several bacteria, has a bigger genome than many and contains genetic information that was previously unknown and thought not possible for viruses. This paper and many recent others generally highlight the underestimation of the ability of viruses.
This paper explores the evolution of the Mimivirus to perform cytoplasmic replication. Since the nucleus provides an optimal, ready-made site for viral replication, the use of the cytoplasm for this function is extremely unusual and maybe even unnecessary. However, the Mimivirus has turned to building large and elaborate replication ‘factories’ within the cytoplasm of its host,
operating seemingly independently. This brings into question our current understanding of the infection strategies of other large DNA viruses of the NCLDV clade. Some works have suggested that this may be made possible by ‘leakage’ of nuclear enzymes. This has been proven for replication of the Vaccinia virus, however this is not yet the case for the Mimivirus.
This paper also applies methods which we have recently been familiarised with such as fluorescent in situ hybridisation, immunofluorescence and general image processing and microscopy. New techniques have allowed researchers to thoroughly investigate the infection cycle of the Mimivirus, presenting the previously mentioned independent replication ‘factories’.
This paper is of great importance in furthering research and knowledge of the Mimivirus. It shows how current techniques can be applied to explore infection strategies, highlights the evolution of the Mimivirus and its relatives, and also opens up a wide range of questions concerning our basic knowledge of viruses, their current status, their evolution and their future.
A review of:
Mutsafi, Y., Zauberman, N., Sabanay, I. and Minsky, A., 2010. Vaccinia-like cytoplasmic replication of the giant Mimivirus. Proc. Natl. Acad. Sci. U. S. A, 107, pp. 5978-5982.
1 comment:
Hi Sami
I think we did well today!!
I have been trying to find out more about the stargate opening of the outer capsid but it seems no one knows yet how it opens. We would expect such a thing to require some sort of enzyme and energy to be able to do this. Not bad for an innate organism like a virus? I will let you know if I find out more.
Post a Comment