Figure 7.

AMPK is activated and phosphorylated in response to AICA riboside and phenformin in LKB1^+/+ but not in LKB1^-/- MEF cells. Cells immortalized from control embryos LKB1^+/+ and LKB1^-/- knockout embryos [14], were incubated with AICA riboside (2 mM) or phenformin (10 mM) for 1 hour. Lysates were prepared and AMPK activity (expressed as units per mg total lysate protein) determined in immunoprecipitates made using a mixture of anti-AMPKα1 and anti-AMPKα2 antibodies. Lysates were also analyzed by SDS gel electrophoresis and blots probed using anti-LKB1, anti-AMPKα1/β2, and anti-pT172 antibodies.