Journal: Science Advances
Article Title: Phosphorylation of shiftless is important for inhibiting the programmed −1 ribosomal frameshift
doi: 10.1126/sciadv.adw7471
Figure Lengend Snippet: ( A ) EMSAs of the indicated SFL and SFL variants with the 55-nt −1 PRF-short RNA. Increasing protein concentrations used in EMSA are indicated on top of the gels. Representative of three independent experiments. ( B ) SDS-PAGE analysis of purified insect cell–expressed SFL, E. coli –expressed SFL, and insect cell–expressed SFL mutants S249A, T250A, T253A, S256A, S249D, T250D, T253D, and S256D. ( C to G ) BLI titrations of SFL mutants binding with −1 PRF-short RNA. Biotinylated −1 PRF-short RNAs were immobilized on SA biosensors for binding with SFL in solutions with a concentration series indicated on the top right. Binding kinetic parameters K D , k on , and k off are shown on top of each graph. Dashed lines are the fitting of the experimental data. Representative of two independent experiments. (C) Mutants S249A and S249D. (D) Mutants T250A and T250D. (E) Mutants T253A and T253D. (F) Mutants S256A and S256D. (G) Nonphosphorylated SFL expressed from E. coli . ( H ) Histogram illustrating the comparison of K D values of WT SFL and that of SFL mutants from the fitting of representative datasets. Error bars represent the fitting-derived K D error. ( I ) Western blot analyses of insect cell–expressed SFL alone, SFL treated with ALP of different enzyme units (2.5 and 5.0 U), and E. coli –expressed SFL; the samples were stained with SFL pAb or pan phosphor-Ser/Thr mAb. Representative of two independent experiments.
Article Snippet: E. coli BL21 (DE3; Thermo Fisher Scientific, EC0114) cells were grown in Luria-Bertani (LB) medium.
Techniques: SDS Page, Purification, Binding Assay, Concentration Assay, Comparison, Derivative Assay, Western Blot, Staining