FIG. 3.
Schematic representation of the VZV DNA between ORFs 20 and 21. The VZV genome consists of unique long (UL) and unique short (US) segments of DNA, each bounded by inverted and repeated DNA sequences (TRL/IRL and IRS/TRS). ORFs 20 and 21 are oriented in opposite directions, and both map within the SalI C fragment (positions 23454 to 35936) within the UL. The 284-bp DNA segment separating ORFs 20 and 21 contains one potential IE62 binding site and three TATAA-like boxes. The 5′ start site of gene 21 transcription is located at nt 30681, and the 3′ end of the transcript has been mapped to nt 33888 and nt 33895 (7, 10). The boundary of the CAT reporter constructs used to locate the VZV gene 21 promoter are shown.