Virus transcription

[Francisco Muril Zerbini]

On 18 May 1995 DANDERSON at prl.pulmonary.ubc.ca wrote:

> I have though about this and have often wondered (as most 
> picornavirologist have) just what is the role of VpG at the 5' end of the 
> positive strand genome?  If it is involved in priming, why is it on the 
> 5' end of the positive strand.  Generally a priming protein (if I'm 
> correct) is associated with the strand that is read during transcription 
> (in this case the negative strand).  Is this a different mechanism 
> and VpG is transfered during transcription initiation?  Why have 100 nts 
> if secondary structure if it is not important in positive strand synthesis?  
> Is VpG involved in translation and has just been ignored for no 
> particular reason? 

Volume 1 of "RNA Genetics" (CRC Press) has an excellent chapter on RNA
replication in Comoviruses, by Rik Eggen and Ab van Kammen (Comoviruses
are picorna-like plant viruses). There's a very good description of the
role of the VPg in RNA replication/priming, and an interesting model is
proposed. Most of your questions are answered there. 

Murilo
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| Murilo Zerbini                   | Out of 3,000,000,000 DNA nucleotides, |
| Dep. of Plant Pathology          | human beings and chimpanzees have     |
| University of California, Davis  | 2,999,400,000 in common.              |
| fmzerbini at ucdavis.edu            |                                       | 
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