... proteolyticcomponent of the toxin, and cleaves six members of the mitogen-activatedprotein kinase kinase family after being delivered to the cytosol by the cell-binding component of the toxin, protective ... antigen. The effect of cleavingthese mitogen-activated protein kinase kinases is to interfere with extracellu-lar signal-related kinase (ERK), p38 and c-Jun N-terminal kinase signaling.Here, ... signal-related kinase; HA, hemagglutinin; IL, interleukin; JNK, c-Jun N-terminal kinase; LeTx, lethal toxin; LF, lethal factor;MAPK, mitogen-activated protein kinase; MAPKK, mitogen-activated protein kinase...