Virus transcription

[DANDERSON at PRL.PULMONARY.UBC.CA]

ijiwaru at nyc.pipeline.com (Lyle Najita)wrote:

 
>The retention of the 5' uridines could be due to VpGpUpU priming, if you
>will indulge those of us willing to believe that it is more than an
>artifact.  I'm not partial to either host factor priming or VpGpUpU
>priming, but would like to believe that host factor works at the 3' end of
>the plus-strand and the VpGpUpU at the 3' end of the minus-strand. 
 
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? 

Hummm, ......more thinking! 

Dan