C-terminal RNA-binding domain (RBD) domain of Ebola virus VP35 phosphoprotein and related proteins
This family includes the C-terminal RNA-binding domain (RBD) of the P protein of viruses belonging to the Filoviridae family, such as Ebola virus or Marburg virus. VP35-RBD contains two subdomains: an alpha-helical subdomain and a beta-sheet subdomain. Virus infection typically activates host innate immunity, including the interferon (IFN) signaling pathway; VP35-RBD binds double-stranded RNA (dsRNA) inhibiting IFN-alpha/beta signaling. The family Filoviridae belongs to the order Mononegavirales which are nonsegmented negative-stranded RNA viruses (NNVs). The genomes of NNVs are encapsidated by their nucleocapsid (N) proteins to form N-RNA complexes which serve as a template for transaction and replication. The C-terminus of P protein binds nucleocapsid. P protein plays multiple roles in transcription and translation, which include acting as a chaperone of nascent nucleoprotein (N), and as a cofactor of the viral polymerase (L) where P forms a two-subunit polymerase with a large catalytic subunit (L) and stabilizes the polymerase on its template of N-RNA.