FIG. 6.
(A) The increase in proliferation following expression of T antigen in enterocytes is reduced in the absence of E2F2 alone or of both E2F2 and E2F3a but not in the absence of E2F1. Total numbers of positive BrdU-labeled cells in either the villi or the crypt were counted and averaged for each group of mice and are represented in the graph. Error bars indicate the standard deviation in each group. (B) Ectopic proliferation in TAgwt; E2F2 KO mice does not correlate with increased E2F1 protein levels. E2F1 expression was measured by Western blotting against a positive control, nontransgenic intestinal samples, or intestinal samples expressing TAgwt in the presence or absence of functional products of E2F2 alone or of both E2F2 and E2F3a. Depletion of E2F2 was confirmed for the corresponding samples.