IUBio Biosequences .. Software .. Molbio soft .. Network News .. FTP

viruses, evolution, and net traffic

Leonard Pattenden ddlpatte at mailbox.uq.edu.au
Thu Oct 9 11:28:38 EST 1997


On 8 Oct 1997, Ed Rybicki wrote:

> > From:          Leonard Pattenden <ddlpatte at mailbox.uq.edu.au>
> > Subject:       Re: viruses, evolution, and net traffic
> 
> > My understanding of Viral evolution - as a protein chemist working in HIV
> > - is that viruses are escaped genes. Thus - for example - in many
> > retroviruses we see the aspartyl protease which cleaves the GAG-POL 
> polyprotein
> ..
> > smaller homodimeric protease we see today. The implication of my beliefs
> > to your suggestions, is that propensities for particular viral types must
> > reflect the availability of the machinery within the cell. Ie if a plant
> > cell can produce reverse transcriptase which could be incorporated
> > somehow into a virus, then the feasability of an RNA virus is
> 
> Okayeeee...first problem: not all viruses can be boxed with 
> retroviruses as "escaped genes", at least, not as RECENTLY escaped 
> genes.

Fair enough, but the point is still valid, retroviruses was an example.

  In fact, there are no classical retroviruses (except maybe 
> some retrotransposons which turn out to be infectious) in plants; 
> only pararetroviruses of presumably ancient lineages (in that ALL 
> retroviruses look MUCH more like each other than badna- and 
> caulimoviruses look like each other).

Interesting, but the arguement still stands.

> 
> Second problem: you will find some mammal-infecting viruses in the 
> same superfamilies (based on polymerase homologies) as plant 
> viruses...seeing as land plants and mammals diverged some 10exp9 
> years ago...see what I mean?


Yes. I understand your point. Quite frankly, how much faith would you
hold to polymerase homology in light of the size of a viral genome and the
period of time you have put forward for divergence?


Len...









More information about the Virology mailing list

Send comments to us at biosci-help [At] net.bio.net