Plasmid Constructs—A 3.3-kb human PKD1 promoter fragment (3,346 to 33) in the promoterless luciferase reporter
vector pGL3-Basic (Promega) was originally generated in our
lab (14). Promoter deletion constructs (1.3 kb, 2.0 kb, 1.7 kb,
1.0 kb, and 200 bp) cloned in pGL2-Basic and/or pGL3-Basic
were previously described (14–16). The mammalian expression construct for the activated CA-Mekk1 (pFC-MEKK) was
from Stratagene. This construct represents the C-terminal
end (293 amino acids) of full-length (1,493 amino acids)
Mekk1 (23). p53 and dominant-negative p53 mutant were
generous gifts of Dr. Samir El-Dahr (Tulane University Health
Sciences Center). HCT116 p53/ cells were a gift from the
Vogelstein lab (The Johns Hopkins University).