Different basal levels of transcription affect library generation
(A) An unknown fraction of the total RNA harvested is labeled with EU.
(B) Biotin-azide is conjugated to EU via a “click” reaction.
(C) All biotinylated RNAs are pulled down on streptavidin-coated magnetic beads.
(D and E) (D) cDNA libraries are generated directly off the beads and the (E) relative gene expression between populations is misrepresented after library amplification.