Fig. 2. Mutation of ser-696 or ser-787 to alanine blocks their phosphorylation by cyclin B-cdc2 kinase. 2D phosphopeptide mapping of recombinant MAP4 bacterial proteins, showing wild-type (A) and wild-type mutated singly (B,C) or doubly (D) at residues 696 and 787 from serines to alanines and subjected to cyclin B-cdc2 kinase phosphorylation as described previously (Ookata et al., 1997).