In article <94278.102932IO00865 at MAINE.MAINE.EDU>, Ethan Strauss <IO00865 at MAINE.MAINE.EDU> writes...
>In article <1994Oct5.001317.18360 at marlin.jcu.edu.au>, robert at chironex.jcu.edu.au>says:
>>>>In article <36r760$u7 at hermod.uio.no> ohungnes at bioslave.uio.no (Olav Hungnes)
>>writes:
>>Is there any evidence that amongst the (+)-strand virions there are some
>>(-)-strand
>>containing particles also ? At a pinch, with todays PCR technology we should
>>be
>>able to answer that question if it hasn't already been done.
>>I have actually done this experiment for Potato Virus X.
>To the limit of our ability to detect it (pretty small amounts)
>there is not - sense PVX packaged in with the + sense in the virions.
>I don't know about other + sense viruses.
>About why - sense viruses exist I think that perhaps the best answer
>is: Why not? Evolution just does whatever happens to work at the
>time, not what would be objectivly the "best".
>Ethan Strauss
Cucumber mosaic virus sometimes harbors a molecular parasite satellite RNA,
and the packaged strand of the satellite has by convention been called the
(+) strand, even though it doesn't encode any proteins. Recently we have
found a small but significant amount of (-) strand satellite RNA in virion
RNA, by PCR. We haven't yet checked the genomic RNAs.
M.J. Roossinck
The S.R. Noble Foundation
