IP-MS:Protein precipitated by antisense (AS) DNA oligomers crossing the junction site of circNEIL3

To identify the circNEIL3 interacting protein, we performed RNA pull-down assays after transfecting into cells with biotin-labeled sense (S) or antisense (AS) DNA oligomers crossing the junction site of circNEIL3, and the pull-down proteins were subjected to SDS-PAGE and Coomassie blue staining. ~45 kDa Band pulled down by the AS probe was specifically excised , digested and used for mass spectrometry analysis.