(a) Quantification of motif plasmid expression in HEK293T cells by qPCR with primers against eGFP. (n=3 biologically independent experiments, bars represent mean signal and error bars denote s.e.m) (b) RaPID-Western of TNF-CDE vs two scrambled sequence controls (scr1 and scr2). HA recognizes the epitope tagged LN-HA-BioID2* fusion, which serves as a self-biotinylated streptavidin pulldown internal control. Labeling performed for 1 min (n=3 biologically independent experiments, representative image shown) (c) RaPID-Western of TNF-CDE vs two scrambled sequence controls (scr1 and scr2). HA recognizes the epitope tagged LN-HA-BASU* fusion, which serves as a self-biotinylated streptavidin pulldown internal control. Labeling performed for 1 min (n=3 biologically independent experiments, representative image shown) (d) Quantification of RaPID-Westerns with BASU 1 min labeling. (n=3 biologically independent experiments, bars represent mean signal and error bars denote s.e.m) (e) RaPID-Western blots of TNF-CDE and scrambled controls using conventional E. coli BirA* with 18hrs of labeling. Western blotting of RC3H1 pulldown, RaPID (λN-HA-BirA*) fusion protein, which serves as an self-biotinylated internal control detected by HA antibody, and RC3H1 in the lysate are shown. (n=3 biologically independent experiments, representative image shown) (f) Quantification of RaPID-Western of TNF-CDE and scrambled controls using conventional E. coli BirA* with 18hrs of labeling (n=3 biologically independent experiments, bars represent mean signal and error bars denote s.e.m) (g) Signal-to-noise ratio (SNR) comparison between E. coli BirA* at 18hrs and BASU at 1min using TNF-CDE vs scrambled control RNA motifs (h) RaPID-MS SAINT score vs Fold Change (FC) plot for EDEN15 with BASU at labeling time of 30 minutes (i) RaPID-MS SAINT score vs Fold Change (FC) plot for IRE (UTRP 35) with BASU at labeling time of 30 minutes. Source data