cDNA synthesis

[Edward Wang]

I am running into consistent problems with my cDNA synthesis.  I am 
reverse transcribing 5 ug of oligo dT selected mRNA (from rat mesangial 
cells).  First strand looks fine on a gel exposed O/N.  The second 
strand, on a regular gel stained with etBr shows a very bright band at 
around 1.5 kb, along with the smear which is expected for a cDNA 
synthesis rxn of total mRNA.  The band showed up consistently using 
different batches of reagents and mRNA preps.  The band is still very 
visible after a restriction digest, suggesting the enzyme doesn't cut 
the band or cut it very poorly.  I don't think it is contamination 
because I've used several different batches of reagents and for the 
amount I'm running on the gel, the source of contamination would have to 
be in the order of several ug/ul.  Anybody have any idea as to what this 
band might be?  
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Edward H. Wang                 * 
Staff Resch. Assc.             *
Dept. Internal Med. -Nephrology*
UC Davis                       *
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