Protein that assembles into highly ordered structures and provides a specific site for viral DNA replication. Probably anchors the viral DNA replisome to the host membrane. Homomultimer. Self-associates into large complexes forming long filamentous structures (PubMed:2526779) (PubMed:9774353, PubMed:15883018). Interacts (via N-terminus) with the primer terminal protein (PubMed:11032825). Interacts with host FtsZ protein (PubMed:23836667). The hydrophobic C-terminus is involved in the association with the host membrane (PubMed:11032825). The coiled coil region is involved assembly into protofilament sheet structures (PubMed:11283004). Belongs to the phi29likevirus DNA replication protein 1 family.