Fig. 9. PS2 integrin-expressing S2 cells spread on purified C-terminal Tsp polypeptide. (A) S2 cells lacking or expressing PS2m8 integrins were plated on purified Tsp CTD polypeptide (CTD KGD), Tsp CTD polypeptide with a mutation in the putative integrin-binding site KGD>LGE (CTD LGE), or on no ligand (Christopherson et al., 2005). (B) Coomassie Blue staining of purified Tsp CTD polypeptide, wild type (CTD) and the KGD>LGE mutant protein (CTD^*). (C) S2 cell spreading as seen by phase microscopy; arrowheads show non-spread (left) versus spread (right) cells. (D) Spreading of cells expressing PS2m8 integrins, PS2m8 integrins containing a mutation that severely impairs ligand binding (mutPS2m8), or PS1 integrins plated on purified Tsp CTD polypeptide or no ligand. The percentage of spread cells is shown. Numbers represent the mean and standard error of three experiments.