The Origin and Evolution of Viruses as Molecular Organisms
Correspondence: (Login to view email address)
- Centers for Disease Control and Prevention, Atlanta, GA 30333
PDF (607.3 KB)
- Document Type:
- Manuscript
- Date:
- Received 21 October 2009 18:19 UTC; Posted 23 October 2009
- Subjects:
- Genetics & Genomics, Microbiology, Evolutionary Biology
- Abstract:
Viruses are the most abundant life forms and the repertoire of viral genes is greater than that of cellular genes. It is also evident that viruses have played a major role in driving cellular evolution, and yet, viruses are not part of mainstream biology, nor are they included in the Tree of Life. A reason for this major paradox in biology is the misleading dogma of viruses as viral particles and their enigmatic evolutionary origin. This article presents an alternative view about the nature of viruses based on their properties during the intracellular stage of their life cycle, when viruses express features comparable to those of many parasitic cellular species. Supporting this view about the nature of viruses is a novel hypothetical evolutionary model for their origin from parasitic cellular species that fused with their host cells. By losing their membrane and cellular structure within the host cell, these new types of parasitic species gained full access to precursors for the synthesis of their specific molecules and to the host’s information processing machineries, such as translation, which created unique parasitic and evolutionary opportunities. To identify viruses during their intracellular stage of their life cycle, in which their specific molecules are free or dispersed within the host cell, this paper introduces the concept of “molecular structure” and labels viruses as “molecular organisms.” Among the extant viruses, the life cycle of poxviruses and other complex viruses that fuse with their host cells provides compelling evidence for the fusion model. One of the most remarkable implications of fusion model is that new viral lineages originated from parasitic cellular species throughout the history of life, and that this process might still be active. Surprisingly, it appears that several parasitic cellular species are currently evolving into molecular organisms. More remarkably though, according to this model, several parasites that are currently classified as cellular organisms are in fact genuine molecular organisms. The current evidence for the fusion hypothesis is strong and it is fully testable using both experimental and phylogenetic approaches. The academic and research implications of this model, which supports the inclusion of viruses in the Tree of Life, are highly significant. Some of these implications are discussed in more detail in two other articles of this series, which presents a unifying model for the origin and evolution of cellular and viral domains, including the origin of life.
Discussion
- Votes:
-
3 votes
- Comments:
-
1 comment
- (Login to share with a colleague)
Additional information
- License:
- This document is licensed to the public under the Creative Commons Attribution 3.0 License
- How to cite this document:
-
Bandea, Claudiu. The Origin and Evolution of Viruses as Molecular Organisms. Available from Nature Precedings <http://hdl.handle.net/10101/npre.2009.3886.1> (2009)
- Version info:
-
Other versions of this document in Nature Precedings
None.
Other versions of this document elsewhere on the web
None known.
Claudiu Bandea on 23 October 2009 12:42 UTC
This is one of a series of three papers (1,2,3) that presents a broad, unifying scenario on the origin and evolution of cellular and viral domains, including the origin of life. This scenario challenges the current view about the history of life at the most fundamental level.
Briefly, the first paper, “The Origin and Evolution of Viruses as Molecular Organisms,” questions the current dogma of viruses as viral particles and presents an alternative view about their nature, origin, and evolution (1). In addition to its conceptual implications, the new view about the nature and evolution of viruses has immediate, specific biomedical applications. One of the most pragmatic, potential applications is in a field of transmissible spongiform encephalopathies, which is presented in the second paper, “Endogenous Viral Etiology of Prion Diseases” (2). The third paper, “A Unifying Scenario on the Origin and Evolution of Cellular and Viral Domains,” integrates the new view about the evolution and nature of viruses into a broad, unifying scenario for the evolutionary origin of cellular and viral domains, including the origin of life (3).
Because of the broad topics of these papers, over the last two years, I sent them for review to numerous scientists and research experts in various biomedical fields. As you can see in the Acknowledgements section of these papers, many of these scientists were kind enough to share their thoughts, for which I’m grateful. Here, I would like to address a common concern about the format and the presentation style of these papers.
As mentioned above, the topics addressed in this series are very broad. These topics have been discussed in thousands of publications presenting a myriad of novel ideas, models, and hypotheses. Although the papers in this series are exceedingly long, I could not address, or even mention or reference, many of these previous publications; obviously, this doesn’t do justice to their authors. My intent in this series was to focus on, and outline, what I thought represent novel interpretations, ideas, and models sustaining a broad, unifying scenario on the origin and evolution of cellular and viral domains; this approach might also explain the apparent dogmatic presentation style.
(1) Bandea, Claudiu. The Origin and Evolution of Viruses as Molecular Organisms. Available from Nature Precedings(http://hdl.handle.net/10101/npre.2009.3886.1), 2009
(2) Bandea, Claudiu. Endogenous Viral Etiology of Prion Diseases. Available from Nature Precedings (http://hdl.handle.net/10101/npre.2009.3887.1), 2009
(3) Bandea, Claudiu. A Unifying Scenario on the Origin and Evolution of Cellular and Viral Domains. Available from Nature Precedings (http://hdl.handle.net/10101/npre.2009.3888.1), 2009