Figure 8. Post-translational processing of progastrin in HIT-T15 cells transfected with preprogastrin and VMAT2.
A and B, representative HPLC traces of [35S]sulphate-labelled G17 and G34, after 80 min chase following 15 min pulse labelling in a control clone expressing preprogastrin (A), and in a clone co-expressing VMAT2 (B). C, the time course of cleavage of G34 in VMAT2-expressing cells (•) and in control cells (□) (bars are means ±s.e.m. for 3 independent experiments). D, the inhibition of G34 cleavage in cells expressing VMAT2 by 1 μm reserpine or tetrabenazine (▪); **P < 0.01 (t test) vs. control; in sham co-transfected cells, reserpine and tetrabenazine had no effect. Mean of at least 3 independent experiments; similar results were obtained with 2 separate clones of preprogastrin/VMAT2 expressing cells, and of preprogastrin/sham co-transfected cells.