Non-Leukemogenic Forms of ICN Fail to Rescue 8946 Cell Line Growth and do not Transactivate Myc.

(A) Comparison of rescue of 8946 cells by various ICN polypeptides following doxycycline-mediated withdrawal of MYC. 8946 cells were transduced with MigRI viruses, sorted for GFP positivity, and then treated with doxycycline (20 microgram/ml) for up to 8 days. Cell numbers at each time point are shown. (B, C) 8946 cells transduced as in (A) were harvested after 24 hr of treatment with doxycycline (20 microgram/ml) or vehicle (PBS). Levels of Myc (B) and Deltex1 (C) mRNAs were determined by qRT-PCR.