Labelling oligo with biotin during synthesis for EMSA - (Oct/16/2005 )

I'm a novice in EMSA. And I reand the non-radio labelling for EMSA, like digoxin and biotin in this forum. Since biotin-labelled nucleotide can be added during the synthesis, why don't use thise service directly for EMSA? Thanks.

I think you probably can use biotinylated oligos directly from the company. My old boss anneals one biotinylated oligo plus the non-biotinylated reverse complement. He uses them to pull down activated transcription factors using streptavidin-agarose but I don't see why they wouldn't work in a non-radioactive EMSA.

Ceri

make sure the biotinylation that you order with the oligo synthesis, is END-LABELLING

if you get labelling along the entire oligo it can interfere with TF binding

good luck