Fig. 3

Highly conserved septin residues are involved in GTP-binding and interactions at G- and NC-interfaces. a) Conserved residues correspond to predicted interacting residues in interfaces. Solid line represents Shannon-Jensen sequence conservation; shaded curves indicate values above 0.5. Red columns: proportion of taxa where a residue interacts in the NC interface. Blue columns: proportion that interact in the G interface. GTP-binding residues are indicated with black arrows. The generalized diagram of S. cerevisiae CDC3 from Pan et al., [15] is shown to scale. b) Diagram of a septin monomer showing the organization of interface residues at the NC and G interfaces. The curved line at the top represents a coiled-coil. c) Model showing how monomers interact to form heterooligomers. The interacting group (ig) residues, colored as in b), indicate predicted residue interactions between septin partners. Not to scale