Figure 3

Expression of AAV2 structural proteins from yeast the galactose-inducible promoter Gal1. (A): pYESIntronCap-transformed cells were first grown for 12 h in glucose and then transferred to galactose medium for 4 and 8 h of induction. Mid-log phase cells were collected at each of these time points and equal amounts of the total cell lysates (~50 μg), were analyzed for Cap protein expression by Western blot using mAb B1. VP3 was the only Cap protein detected and only in the extract 2 (insoluble fraction). Its relative amount was the highest in 12 h glucose samples, diminished after 4 h induction and was no more detectable upon 8 h of galactose induction. (B): pYESVP1KM-transformed yeast cells were exposed to galactose for different times, as indicated on the top, and equal amount of corresponding protein (~50 μg) extracts was analyzed for Cap protein expression using mAb B1. The majority of VP1 proteins were found in extract 2 (insoluble fraction). Extracts from cells transformed with empty vector, pYES2 were used as negative controls (−control).