Structure of G47Δ. (a) Schematic of the HSV-1 genome
showing the regions modified in G47Δ. The HSV-1 genome consists of
long and short unique regions (Ul and Us) each
bounded by terminal (T) and internal (I) repeat regions (Rl
and Rs). The parental virus G207 was engineered from
wild-type HSV-1 strain F by deleting 1 kb within both copies of the
γ34.5 gene and inserting the E.
coli lacZ gene into the ICP6 coding region.
G47Δ was derived from G207 by deleting 312 bp from the ICP47 locus,
as indicated. (b) Map of the ICP47 locus showing
locations of the overlapping 3′ coterminal transcripts (US10, US11, and
ICP47), ORFs (thick arrow), and ICP47 splice junctions (∧).
(c) Map of plasmid pIE12Δ used to generate deletion by
homologous recombination with the indicated flanking sequences. Whereas
US11 is regulated as a true late gene in wild-type
HSV-1, deletion between the indicated BstEII and
EcoNI sites places US11 under control of
the ICP47 immediate-early promoter. Restriction site
abbreviations: B, BamHI; Bs, BstEII; EN,
EcoNI; Nr, NruI; E,
EcoRI.