Fig. 7. Northern blots for BiP. Lanes 1-4: cells were transfected with GH or empty vector and incubated without or with 10 mM DTT for 6 hours. Lanes 5-7: cells were transfected with empty vector and treated with 1 or 10 µg/ml tunicamycin for 3 hours, then switched to drug-free medium. Lanes 8 and 9: cells were transfected with empty vector or mutant preproinsulin encoding insulin with V3A and C7S in the A chain. RNA was isolated after 24 hours. Blots were probed for BiP mRNA, then stripped and reprobed for cyclophilin A (CyA).