Multiple docking sites on substrate proteins form a modular system that mediates recognition by ERK MAP kinase

The amino acid sequence FXFP serves as docking site to mediate ERK nitrogen-activate protein (MAP) kinase binding to substrates in protein families. MAP kinases phosphorylate certain groups of substrate proteins. ERK substrates have been predicted and peptide inhibitors of ERK have been designed, based on findings including that that FXFP is specific for ERK, but that the D box mediates binding to ERK and JNK MAP kinase. It appears that partially overlapping substrate specificities of ERK and JNK come from recognition of unique shared docking sites.