An HSV-1 containing the rat beta-glucuronidase cDNA inserted within the LAT gene is less efficient than the parental strain at establishing a transcriptionally active state during latency in neurons.
The herpes simplex virus vector 17/LAT-RGUSB has previously been shown to express beta-glucuronidase enzyme activity stably in the trigeminal ganglia and brain stems of beta-glucuronidase-deficient mutant mice. However, the number of beta-glucuronidase expressing cells in trigeminal ganglia latently infected with 17/LAT-RGUSB was smaller than expected. Using normal mice for further characterization of 17/LAT-RGUSB latent infection, no appreciable differences were found between the vector and wild-type virus in: (1) their abilities to replicate in acutely infected ganglia; (2) their abilities to reactivate from latently infected ganglia: or (3) the quantities of viral DNA in tissues during the acute or the latent phases of infection. Using a minor LAT (mLAT)-specific probe to detect transcription by in situ hybridization, it was found that the intensity of the signal from individual cells latently-infected with 17/LAT-RGUSB or wild-type virus was similar. However, the vector-infected ganglia had only 20% as many positive cells as in wild-type infection. These data suggest that 17/LAT-RGUSB virus established latency similarly to wild-type virus, but that the LAT-promoter driven gene expression was compromised.
Deshmane
S L
SL
Wistar Institute, Philadelphia, PA 19104, USA.
Valyi-Nagy
T
T
Block
T
T
Maggioncalda
J
J
Wolfe
J H
JH
Dillner
A
A
Fraser
N W
NW
D000818:Animals; D018076:DNA, Complementary / Q000235:genetics; D004279:DNA, Viral / Q000032:analysis; D005260:Female; D015967:Gene Expression Regulation, Viral; D018014:Gene Transfer Techniques; D005814:Genes, Viral / Q000235:genetics*; D005822:Genetic Vectors / Q000235:genetics*; D005966:Glucuronidase / Q000235:genetics*; D018259:Herpesvirus 1, Human / Q000235:genetics* / Q000254:growth & development / Q000502:physiology; D051379:Mice; D008807:Mice, Inbred BALB C; D009474:Neurons / Q000821:virology*; D011401:Promoter Regions, Genetic / Q000235:genetics; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D014158:Transcription, Genetic / Q000235:genetics; D012668:Trigeminal Ganglion / Q000821:virology; D014775:Virus Activation; D017735:Virus Latency / Q000235:genetics*; D014779:Virus Replication
D018076:DNA, Complementary; D004279:DNA, Viral; D012333:RNA, Messenger; D005966:Glucuronidase