Mechanism of
zinc-finger antiviral protein (ZAP) recognition of specific target RNA, and the process by which ZAP coordinates downstream RNA degradation (left). ZAP-RNA complex protein
ribbon diagram (right).
Antiviral proteins are
proteins that are induced by human or animal
cells to interfere with
viral replication. These proteins are isolated to inhibit the
virus from replicating in a host's cells and stop it from spreading to other cells.[citation needed] The
Pokeweed antiviral
protein and the Zinc-Finger antiviral protein are two major antiviral proteins that have undergone several tests for viruses, including
HIV and
influenza.[citation needed]
Pokeweed antiviral protein
Pokeweed antiviral protein (PAP) is a
ribosome inactivating protein that provides
pokeweed plants protection against both viral and fungal infections.[1] It also protects other types of plants that have genetically engineered to express RAP that do not normally do so.[1]Recombinant PAP has also been proposed as a treatment of human diseases such as
AIDS and cancer.[2][3]
ZC3HAV1
ZAP (Zinc finger Antiviral Protein) is encoded by the
ZC3HAV1 gene[4] whose expression is induced by
interferon and helps fight a number of viral infections including influenza.[5]
IFITM3
Interferon-induced transmembrane protein 3 (
IFITM3) inhibits the replication of number of enveloped RNA viruses including
influenza A,
HIV and the
Ebola and
Dengue viruses.[6] Consequently pharmacological induction of IFITM3 potentially could be used to treat a number of viral infections.[5]
Protein kinase R
Protein kinase R is interferon stimulated and activated either by
double-stranded RNA (occurring as an intermediate in RNA viruses replication) or by other proteins. It is able to phosphorylate the eukaryotic translation initiation factor eIF2α thus inhibiting further cellular mRNA translation.[7]
^Rajamohan F, Engstrom CR, Denton TJ, Engen LA, Kourinov I, Uckun FM (July 1999). "High-level expression and purification of biologically active recombinant pokeweed antiviral protein". Protein Expression and Purification. 16 (2): 359–68.
doi:
10.1006/prep.1999.1084.
PMID10419833.