Detection of latency-related viral RNAs in trigeminal ganglia of rabbits latently infected with herpes simplex virus type 1

Abstract

Using a combination of in situ hybridization and Northern (RNA) blot analysis, we investigated herpes simplex virus type 1 (HSV-1) transcriptional activity in an ocular rabbit model of HSV-1 latency. Radioactively labeled cloned fragments, representing virtually the entire HSV-1 genome, were individually hybridized to RNA in sections of trigeminal ganglia taken from rabbits during the latent phase of infection with HSV-1 (McKrae). Our results suggest that two discrete latency-related RNAs (LR-RNAs) may be present. The LR-RNAs were localized mainly in the nuclei of neurons. The more abundant LR-RNA was detected in approximately 3% of all neurons examined and was designated major LR-RNA. The other LR-RNA, designated minor LR-RNA, was detected in approximately 0.3% of neurons from latently infected rabbits. The genes for the LR-RNAs mapped in the vicinity of the immediate-early gene ICPO (also designated IE110). The gene for the major LR-RNA partially overlapped the left (3') end of the ICPO gene. In situ hybridization with single-stranded RNA probes showed that this LR-RNA was of complementary sense to that of ICPO mRNA. Northern blot analysis gave an approximate size for this LR-RNA of 1.8 to 2.2 kilobases. The minor LR-RNA mapped to or near the right (5') end of the ICPO gene. The detection of LR-RNAs suggests the possibility that these RNAs or their products may play significant roles in the initiation and/or maintenance of HSV-1 latency.

Long-read Sequencing Uncovers a Complex Transcriptome Topology in Varicella Zoster Virus

“…(Figure 1). The LAT RNA has been described in every member of the alphaherpesvirus subfamily [59,60], including VZV [9]. We confirmed the existence of four previously detected lytic isoforms of VLT (VLT ly ) of which two are TSS isoforms, one is a splice variant and one is both a TSS isoform and a splice variant (Figure 4, Supplementary Table 2).…”

Compact organization of the hepatitis B virus genome

“…A more analogous example is the herpes simplex virus, where the ICPO gene sequence is transcribed in bot,h directions. The newly discovered anti-sense transcript, or latency-associated transcript,, is the only virus transcript present in latently infected neurons (27)(28)(29)(30)(31)(32).…”

Extraneuronal herpetic latency: animal and human corneal studies

“…Although the present study used full-length cloned HSV DNA and does not indicate which genomic fragments are retained in the cornea during latent HSV infection, laboratory studies on neuronal tissues by other investigators (Stevens et al 1987;Croen et al 1987;Rock et al 1987;Gordon et al 1988) have indicated that the alpha HSV ICPO genome region (from the internal repeated region of the HSV genome) is involved in establishing, maintaining and possibly reversing the viral latency state. Their studies indicate that anti-sense HSV RNA (HSV RNA complementary to the alpha ICPO genome region) appears essential for maintaining latency and that sense HSV RNA appears essential in reactivation and lytic disease.…”

“…Tissue co-culture and immunofluorescent data have allowed recovery of live virus (infectious) and demonstration of viral antigen in neuronal tissues. Now molecular biology techniques, specifically in situ, dot and slot blot hybridization assays, have demonstrated conclusively the presence of specific herpetic nucleic acid sequences, specifically the alpha ICPO genome region, and sense and antisense HSV RNA in trigeminal ganglia and in brain nucleic acid extracts (Stevens et al 1972(Stevens et al , 1987Cabrera et al 1980;Fraser et al 1981;Tenser et al 1982;Croen et al 1987;Rock et al 1987;Gordon et al 1988). Certainly, these neuronal trissues are a key source of virus in recurrent herpetic disease.…”