Expression and RNA-binding of human zinc-finger antiviral protein.
Zinc-finger antiviral protein (ZAP) is a recently isolated host antiviral factor that inhibits the replication of many viruses such as Moloney murine leukemia virus (MLV) and Sindbis virus (SIN) by preventing the accumulation of viral mRNA in the cytoplasm. ZAP comprises four CCCH zinc-finger motifs, the second and fourth of which are responsible for protein activity based on their integrity. Thus far, there have been no reports on whether or not ZAP expressed in Escherichia coli is soluble. Therefore, we expressed N-terminal ZAP (NZAP, 254 amino acids) in E. coli as a fusion protein with several different cleavage sites and protein tags. Cleaved ZAP in soluble form strongly bound to RNA through its four CCCH zinc-finger motifs. Here, we provide evidence indicating that ZAP directly interacted with viral RNA. Each conserved zinc-finger motif of ZAP coordinates a zinc ion using three cysteines and one histidine. These findings suggest that ZAP recruits the cellular RNA degradation machinery for the degradation of viral RNA.
Jeong
Mi Suk
MS
Department of Molecular Biology, College of Natural Sciences, Pusan National University, Jangjeon-dong, Geumjeong-gu, Busan 609-735, Republic of Korea.
Kim
Eun Jung
EJ
Jang
Se Bok
SB
D000595:Amino Acid Sequence; D000818:Animals; D003001:Cloning, Molecular; D006801:Humans; D051379:Mice; D008969:Molecular Sequence Data; D011487:Protein Conformation; D020871:RNA Stability; D012333:RNA, Messenger / Q000378:metabolism*; D012367:RNA, Viral / Q000378:metabolism*; D016601:RNA-Binding Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D051381:Rats
D012333:RNA, Messenger; D012367:RNA, Viral; D016601:RNA-Binding Proteins; C527496:ZC3HAV1 protein, human