PI3K activity down-regulates p27 in M07 cells.
M07 cells were cultured for 18 hours in the presence or absence of GM-CSF with or without 5 μmol/L LY294002. (A) A sample of cells was assayed for cellular DNA content by propidium iodide staining and FACS. (B) Levels of p27, cyclin D3, and cyclin E were analyzed by immunoblotting of 50 μg total cell extracts. Equal protein loading was controled by reprobing with anti-GAP-DH antibody (1:10 000). (C) Cells were plated into 96-well plates at 1 × 105 per well. The viable cells in each well were assayed to their ability to transform 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide into a purple formazan. The absorbance of the samples was measured in an ELISA reader at 570 nm. Data represent the mean ± SE of 5 examinations.
