STI 571 inhibits SLF-dependent activation of mitogen-activated protein (MAP) kinase.

Whole cell lysates of M-07e cells were prepared and immunoblotted with a polyclonal antibody specific for the doubly phosphorylated forms of p44 and p42 MAP kinase (Erk1 and Erk2). The membrane was stripped and reprobed with an antibody for total p44 and p42 MAP kinase. The arrows indicate the locations of p44 and p42 MAP kinase. Representative results from 1 of 8 independent experiments are shown.