RQ1 DNase I digestion of Total RNA

[vaslanzadeh]

I am having problems with the quality of RNA after RQ1 DNase I treatment. After DNase treatment, I use phen/Chlor for RNA purification. I use ethanol for final precipitation. If you look at my bioanlyser trace before and after DNase digesition, there is a large pick after ribosomal RNA. I do not know what this is. If I heat the RNA 6 minutes at 65, I do not see this extra pick but the quality of the RNA drops a lot. I am worried that this pick can affect the Ribo-Zero step and library Prep.

Does anybody had this problem?

Thanks