Positive control for cDNA substraction

[Gilles VACHON]

Hello evryone,

I am trying to set up conditions to perform cDNA substraction. I am using a
first-strand cDNA bank (say, stage A) to subtract common sequences from a
poly-A mRNA pool (say, stage B).
I should end up with a poly-A mRNA mixture enriched with 'stage B-specific'
sequences. 

I have a cloned human cDNA that I would like to use as a positive control,
(assuming that this cDNA is not present in plants).
Therefore, I would like to make poly-A mRNAs from that cDNA (with the T7/T3
system in pBlueScript for instance).

Does that sound nuts or is there anyone on the net having done that already?

Any comments/ideas or references would be helpful and welcome....



P.S: What I will do with these 'specific' sequences is an other story...
(northern, in situ, differential display...?)
Dr. Gilles Vachon
c/o Pr. MACHE
Laboratoire de Biologie Moleculaire Vegetale
CERMO, 3eme etage
Universite J. Fourier, BP 53X
38041 GRENOBLE CEDEX
FRANCE
Tel: (33) 76 51 45 48
fax: (33) 76 51 43 36
e-mail: vachon at bio.grenet.fr