Figure 1.

Both RAB27A and RAB6A Are Subject to Prenylation by Endogenous REP1 from a HEK293-Cell Lysate

(A) Summary table of experimental conditions (1–8) used in prenylation reactions in vitro regarding the amount of total cell lysate (2.5, 5, 10, and 20 μg), concentration of GGT-II (0.5, 1, and 2 μM), and concentration of Rab substrate (RAB27A or RAB6A) (0.16, 0.8, and 4 μM). Positive control (+ve): cell lysate spiked with recombinant fish REP1 (25 nM). (B) Protein expression (human REP1 and β-actin) and biotin incorporation detected in prenylation reaction products following SDS-PAGE and western blot analysis (one example out of three independent experiments). (C) Plots for condition sets assessing biotin incorporation in both RAB27A and RAB6A when different amounts of total cell lysate, concentration of GGT-II, or concentration of Rab substrate were used (n = 3). (D) Summary table of statistical analysis performed in the datasets in (C). Two-way ANOVA tests were run independently for each condition (total cell lysate, concentration of GGT-II, or concentration of Rab substrate) with “condition” and “substrate” as factors. The p values and the significance of each test, as well as the Bonferroni’s multiple comparison test for comparison of RAB27A with RAB6A, are given in detail.