FIG. 6.

p110α and -β regulate c-Myc levels. (A and B) Stable NIH 3T3 cells expressing p110α* or p110β* (A) or NIH 3T3 cells infected with viruses expressing the K802R-p110α or K805R-p110β mutant (B) were arrested in G₀ and incubated for different times after serum addition; c-Myc expression levels were analyzed by WB. Graphs show the mean percentages ± standard deviations (SD) of the c-Myc signals compared to the maximum signal in wild-type cells at 12 h after GF addition (100%) and normalized with the signals of loading controls (n = 3). Transits through S phase are indicated (arrows). P values (P < 0.05; Student's t test) for comparisons of data at 9 and 12 h are shown by asterisks. Gray asterisks show comparisons between control and p110α mutant-expressing cells; black asterisks show comparisons between controls and p110β mutant-expressing cells.