title: cis-acting sequences involved in human immunodeficiency virus type 1 RNA packaging.
abstract: We have previously described a series of human immunodeficiency virus type 1-based vectors in which efficient RNA encapsidation appeared to correlate with the presence of a 1.1-kb env gene fragment encompassing the Rev-responsive element (RRE). In this report, we explore in detail the role of the RRE and flanking env sequences in vector expression and RNA encapsidation. The analysis of a new series of vectors containing deletions within the env fragment failed to identify a discrete packaging signal, although the loss of certain sequences reduced packaging efficiency three- to fourfold. Complete removal of the env fragment resulted in a 100-fold decrease in the vector transduction titer but did not abolish RNA encapsidation. We conclude that the RRE and 3' env sequences are not essential for human immunodeficiency virus type 1 vector encapsidation but may be important in vectors in which a heterologous gene has been placed adjacent to the 5' packaging signal, potentially disrupting its structure.
authors.affiliation: Department of Medicine, Addenbrooke's Hospital, Cambridge, United Kingdom.
authors.forename: J F
authors.initials: JF
authors.lastname: Kaye
authors.forename: J H
authors.initials: JH
authors.lastname: Richardson
authors.forename: A M
authors.initials: AM
authors.lastname: Lever
mesh_terms: D000818:Animals; D001483:Base Sequence; D002213:Capsid; D002460:Cell Line; D002522:Chlorocebus aethiops; D015752:Genes, env; D005822:Genetic Vectors; D016325:HIV Long Terminal Repeat; D015497:HIV-1 / Q000235:genetics / Q000502:physiology*; D006367:HeLa Cells; D006801:Humans; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D009838:Oligodeoxyribonucleotides; D012367:RNA, Viral / Q000096:biosynthesis*; D015183:Restriction Mapping; D017384:Sequence Deletion; D014162:Transfection; D014771:Virion / Q000235:genetics / Q000502:physiology
chemical_list: D009838:Oligodeoxyribonucleotides; D012367:RNA, Viral