I'm doing EMSA and trying to label some supercoiled DNA with P-32. I've found a lot of protocols on 3' and 5' labeling but hardly anything on how to label internally (as in a plasmid). Any ideas on how one might do this?
Thanks, I hadn't thought of that! Is it possible to generate a supercoiled plasmid labeled plasmid through PCR, though? I thought the product would be linearized?
No, I don't think that you can generate supercoiled plasmid without bacteria. Are you performing EMSA with entire plasmid? It may be problematic due to the DNA size.