Extended Data Fig. 4: Ribosomal run-off curves from single cells after addition of Harringtonine.

a, Harringtonine-induced ribosomal run-off curves from single cells. Each curve shows the decay in nascent chain signal intensity from all Cap-dependent and (b) IRES-mediated translation sites within a single cell post-Harringtonine. Run-off curves were phenomenologically fit to a Tanh function to align curves in time for averaging in Fig. 3. The slope of fitted curves at a normalized intensity value of 0.5 was used to estimate the elongation rate. c, Cap-dependent (n = 7 cells) and (d) IRES-mediated (n = 5 cells) translation controls in which no drugs were added. Each gray line shows the total nascent chain signal intensity from all translation sites in an individual cell. The thick black line is a representative cell. Intensity in arbitrary units (a.u.). All cells were imaged for 45 minutes with a 1-minute interval between each capture.