Figure 5. In vitro molecular analysis of the PP1c docking motif in the APAF-1_122–131 domain.

(A) Proteins involved in the control of cell survival pathways with a putative apoptotic signature that combines the two PP1c docking motifs (R/K)-x_(0,1)-V/I-x-F-and F-x-x-R/K-x-R/K. (B) Autoradiogram of the PP1 binding assay on cellulose-bound APAF-1 peptides. 7 overlapping dodecapeptides with a two-amino acid shift scanning the sequence encompassing aa residues 119–141 of the APAF-1 sequence were synthesized on a cellulose membrane. The membrane was incubated with PP1c holoenzyme and subsequently with anti-1c antibodies followed by peroxidase-labelled anti-mouse antibodies. The residues corresponding to the PP1c consensus binding motif are shown in bold.