HERPES-SIMPLEX VIRUS RECOMBINATION VECTORS DESIGNED TO ALLOW INSERTION OF MODIFIED PROMOTERS INTO TRANSCRIPTIONALLY NEUTRAL SEGMENTS OF THEVIRAL GENOME

The use of recombinant viruses has been essential in investigation of the biology of herpes simplex virus (HSV). In this communication we de scribe a number of viral recombination vectors that we have generated for use in promoter structure/function analysis within the context of the HSV-1 genome, We have utilized two regions of the HSV genome that contain genes nonessential for replication in cultured cells-the glyco protein C (gC or U(L)44) locus in the U-L of the genome and the area e ncompassing the promoter and 5' portion of the latency associated tran script (LAT) within the R(L). The vectors were designed to allow inser tion in either orientation within the loci to prevent an artifactual i nfluence on promoters due to the site of insertion. Two different kine tic promoters were analyzed, those controlling expression of the gamma U(L)38 and the beta dUTPase genes, in both loci. All constructs teste d displayed reporter gene mRNA expression with expected kinetics, and we conclude that there are no neighboring cryptic promoter elements th at could interfere with expression studies using the vectors described .