Fig. 6. Depletion of RILP or Vps22 does not affect transferrin trafficking through early endosomes. HeLa cells treated with control RNA (scr), with siRNA against RILP or with siRNA against Vps22 were allowed to bind to ¹²⁵I-labelled human transferrin (hTf) for 1 hour at 0°C. After washing with cold PBS-BSA to remove the unbound hTf, cells were incubated for different times at 37°C to allow internalization of the surface-bound ¹²⁵I-labelled hTf. Internal ¹²⁵I-labelled hTf was estimated as the residual radioactivity after pronase treatment, compared with total bound ¹²⁵I-labelled hTf. Bars, s.e. of triplicate samples.