Figure 4.

Electrophoretic mobility shift assays of AtfB binding in the fas-1, ver-1, omtA, vbs, mycelial cat1, and Mn sod promoters. Aspergillus parasiticus SU-1 was grown for 24, 48, or 60 h at 30°C in YES medium. Enriched nuclear protein extracts were prepared as described in Experimental Procedures. Five micrograms of enriched nuclear protein extracts was added to a P³²-labeled promoter probe for each aflatoxin or antioxidant gene. Anti-AtfB antibodies (YSR) or preimmune serum was added to determine whether these could block protein/DNA interaction (shift inhibition). (A) Fas1-a probe. Nuclear protein extracts were used from 24-, 48-, or 60-h culture. (B) Ver1-b probe. Nuclear protein extracts were used from 24-, 48-, or 60-h culture. (C) OmtA probe. Nuclear protein extracts were used from 48-h culture. (D) Vbs probe. Nuclear protein extracts were used from 48-h culture. (E) Mcat1-a probe. Nuclear protein extracts were used from 24-, 48-, or 60-h culture. (F) Msod probe. Nuclear protein extracts were used from 24-, 48-, or 60-h culture.