Figure 6.

Possible evolution of the Arenaviridae. Members of the Arenaviridae and Filoviridae may have a common ancestor encoding the progenitor of arenavirus and filovirus glycoproteins. Acquisition of the stable signal peptide (SSP) and intracellular zinc-binding domain (ZBD) in the arenavirus glycoprotein complex (GPC) followed divergence from the filoviruses. Mammarenaviruses and reptarenaviruses acquired a zinc-binding protein (Z) following divergence from antennaviruses and hartmaniviruses. Reptarenaviruses then replaced the arenavirus GPC or a progenitor with a filovirus-like class I glycoprotein via recombination.