Figure 9. Cdc42-GDP binds specifically to Cdc10 and dissociates septin filaments.
(A) Representative EM image of negatively stained septin complexes incubated with Cdc42-GppNHp. Scale bar, 100 nm. (B) Representative EM image of negatively stained septin-Cdc42-GDP-complexes. (C) Same as (B) but at 10× higher concentration of Cdc42-GDP. (D) Gel filtration chromatography and SDS-PAGE of the septin-Cdc42-GDP complex. (E and F) Representative class averages of septin-Cdc42-GDP complexes. The asterisk indicates the additional density corresponding to Cdc42-GDP. Arrows indicate single septin proteins. Scale bar, 10 nm. (G and H) Representative class averages of the septin-Cdc42-GDP complex labeled with antibody against Cdc3. The asterisk indicates the additional density corresponding to Cdc42-GDP. Arrows indicate single septin proteins. The triangle indicates the antibody. (I) Model of the septin-Cdc42-GDP complex. Cdc42-GDP is depicted as yellow circle.