Figure 1. Assembly of coagulation complexes on a PS+ phospholipid membrane.

Coagulation complexes (TF:FVIIa; FVIIIa:FIXa; and FVa:FXa) assemble on a membrane surface. The presence of anionic phospholipids, such as PS (red), facilitate the binding of FVIIa, FIXa, FXa, and prothrombin (PT) by interaction with the Gla domains within the proteins. Phospholipids originating from the outer membrane before disruption of membrane asymmetry are shown in grey.