Figure 1  .

Alkaline β-elimination. HeLa protein western blot. Lanes 1 and 2 preincubated in water, 3-5 in 5 mM NaOH, 6-7 in 10 mM NaOH. Subsequent incubation with anti-p68-positive RA serum (2, 4, 6), anti-p68-negative human control serum (5), anti-p68-positive rabbit serum (1, 3, 7) and anti-p68-negative control serum. Detection with FITC conjugated secondary antibody. p68 was detected by the RA serum antibody after incubation with water (2) and with 5 mM NaOH (4), but not after incubation with 10 mM NaOH (6). p68 was detectable by the rabbit serum antibody even after 10 mM NaOH treatment (7).