title: Intravirion targeting of a functional anti-human immunodeficiency virus ribozyme directed to pol.
abstract: Ribozymes are catalytic RNAs that offer several advantages as specific therapeutic genes against human immunodeficiency virus type 1 (HIV-1). Significant challenges in antiviral uses of ribozymes include (1) how best to express and to deliver this agent and (2) what is the best locale to target ribozymes against HIV-1 RNA. To explore the former, we have previously characterized several vector systems for efficient expression/delivery of anti-HIV-1 ribozymes (Dropulic et al., 1992; Dropulic and Jeang, 1994a; Smith et al., 1997). Here, to investigate an optimal locale for ribozyme-targeting, we asked whether it might be advantageous to direct ribozymes into HIV-1 virions as opposed to the more conventional approach of targeting ribozymes into infected cells. Two series of experiments were performed. First, we demonstrated that anti-HIV-1 ribozymes could indeed be packaged specifically and efficiently into virions. Second, we compared the virus suppressing activity of a packageable ribozyme with its counterpart, which cannot be packaged into HIV-1 virions. Our results showed that although both ribozymes cleaved HIV-1 genomic RNA in vitro with equivalent efficiencies, the former ribozyme demonstrated significantly higher virus-suppressing activity than the latter. These findings provide proof-of-principle that to combat productive HIV-1 replication, intravirion targeting is more effective than intracellular targeting of ribozymes.
authors.affiliation: Molecular Virology Section, Laboratory of Molecular Microbiology, National Institute of Allergy and Infectious Diseases, 9000 Rockville Pike, Bethesda, Maryland 20892-0460, USA.
authors.forename: V
authors.initials: V
authors.lastname: Giordano
authors.forename: D Y
authors.initials: DY
authors.lastname: Jin
authors.forename: D
authors.initials: D
authors.lastname: Rekosh
authors.forename: K T
authors.initials: KT
authors.lastname: Jeang
mesh_terms: D001483:Base Sequence; D002460:Cell Line; D015684:Gene Products, pol / Q000235:genetics* / Q000378:metabolism; D018390:Gene Targeting; D006678:HIV / Q000235:genetics* / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D006868:Hydrolysis; D016337:RNA, Catalytic / Q000235:genetics* / Q000378:metabolism; D012367:RNA, Viral / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014771:Virion / Q000235:genetics* / Q000502:physiology; D019065:Virus Assembly / Q000235:genetics
chemical_list: D015684:Gene Products, pol; D016337:RNA, Catalytic; D012367:RNA, Viral