Sup F selection

Ian A. York iayork at
Fri Mar 3 13:59:41 EST 2000

In article <89ouid$sqs$1 at>,
Rob Jordan <rjordan at> wrote:
>I've inherited a recombinant protein in an old pcDNA1NEO expression vector
>from Invitrogen. This vector has an amber mutation suppressor rather than a
>bacterial antibiotic resistance gene to select transformed clones. This
>isn't a problem I guess, though I'll have to get some new bacteria, but why
>would you make a plasmid like this rather than put an antibiotic resistance
>gene in the plasmid?

Size.  It made the plasmid smaller.  It seemed like a good idea at the
time.  (You need MC1061/p3 as your bacterium, by the way, which is readily
available.  Ask old farts in your department to look in their freezers, if
you can't find it easily.)

>While I'm at it what is the "polyoma origin" for?

SV40 origin provides replication of the plasmid in primate cells
expressing SV40 LT antigen.  Polyoma origin permits replication of hte
plasmid in murine cells expressing the polymoa LT antigen.

    Ian York   (iayork at  <>
   "Blinton did not care for folk lore (very bad men never do), but
   he had to act as he was told."  --Andrew Lang, Books and Bookmen

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