Fig. 9. Effects of selected mutations on RNA and protein stability. (A) Degradation kinetics of unmutated VSG 117 and 519-526 RNA. Cell lines were cultured for 8 hours in medium containing 10 µg/ml actinomycin D to prevent transcription. Samples were taken at 4 hour intervals and a northern blot was probed with VSG 117. (B) Degradation kinetics of unmutated VSG 117, 504-526, 512-526, 519-526, D503C and VSG117TM. Cell lines were cultured for 8 hours in medium containing 50 µg/ml cycloheximide to prevent translation. Samples were taken at different time points and analyzed on a western blot with anti-VSG 117 antibodies. (C) Degradation kinetics of wild-type VSG 117, 504-526, 512-526 and 519-526 in the presence of lactacystin. Cell lines were cultured for 8 hours in medium containing 50 µg/ml cycloheximide and 1 µM lactacystin. Samples were taken at different time points and analyzed on a western blot with anti-VSG 117 antibodies. Aliquots representing 2x10⁴ cells were loaded per lane with the exception of VSG117TM where 2x10⁶ cells were loaded per lane.