Fig. 8: A proposed model of EBOV nucleocapsid assembly and the roles of two VP24 molecules.

Our proposed model describes the two-phase strategy of NCLS formation and function. a The first phase depicts the role of VP24-1 in initial nucleocapsid assembly, highlighting that the interface with NP-1 is critical for the recruitment of VP24 into inclusion bodies (IBs) and termination of genome transcription and replication. This diagram highlights the importance of residue N171 in VP24-1, as a critical binding site for NP. Moreover, VP24-1 R59 and potentially NP-1 H196 are involved in recruiting VP24 to IBs and inhibiting transcription and replication. b The second phase illustrates the involvement of VP24-2 in the structural maturation of the nucleocapsid. Mutations in VP24 K148 and NP R132 at the NP-2–VP24-2 interface and VP24 I35 at the VP24-1–VP24-2 interface are crucial for nucleocapsid assembly. This stage highlights the necessity of these interactions for nucleocapsid formation and the subsequent transport of mature NCLS for the formation of progeny virions.