Assuntos
Regulação da Expressão Gênica/imunologia , Rejeição de Enxerto/imunologia , Interleucina-1/genética , Interleucina-6/genética , Transplante de Rim/imunologia , Artéria Renal/imunologia , Fator de Crescimento Transformador beta/genética , Fator de Necrose Tumoral alfa/genética , Biomarcadores/sangue , Rejeição de Enxerto/genética , Rejeição de Enxerto/patologia , Humanos , Transplante de Rim/patologia , Reação em Cadeia da Polimerase , Artéria Renal/patologia , Fator de Crescimento Transformador beta1 , Transplante HomólogoRESUMO
The earliest events within the peripheral mammalian nervous system that cause herpes simplex virus type 1 (HSV-1) to reactivate from latency are unknown but are highly likely to include altered regulation of cellular transcription factors. Using gene array analysis, we have examined the changes that occur in cellular mRNA levels in mouse trigeminal ganglia following explantation, a stimulus that results in HSV-1 reactivation from latency. We have detected both increased and decreased expression levels of particular cellular transcripts, which include RNAs encoding neuronal factors, transcription factors, and factors involved in the cell cycle. Among the transcription factors that are upregulated is Bcl-3, a coactivator for NFkappaB. We have confirmed these increases in Bcl-3 transcription levels using reverse transcription-PCR and S1 nuclease protection assays. In addition, we have shown Bcl-3 upregulation at the protein level. Importantly, Bcl-3 RNA levels were found to increase specifically in neuronal cells within the trigeminal ganglia. We discuss a potential role for this factor in upregulating ICP0 transcription, which is an important viral event for initiation of HSV-1 reactivation.
Assuntos
Herpesvirus Humano 1/fisiologia , Sistema Nervoso Periférico/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Ativação Viral , Animais , Proteína 3 do Linfoma de Células B , Western Blotting , Feminino , Perfilação da Expressão Gênica , Herpesvirus Humano 1/genética , Hibridização In Situ , Camundongos , Camundongos Endogâmicos BALB C , NF-kappa B/genética , NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas/análise , Proteínas Proto-Oncogênicas/genética , RNA Mensageiro/análise , Fatores de Tempo , Fatores de Transcrição , Regulação para Cima , Latência ViralRESUMO
The detailed mechanism which governs the choice between herpes simplex virus (HSV) latency and reactivation remains to be elucidated. It is probable that altered expression of cellular factors in sensory neurons leads to induction of HSV gene expression resulting in reactivation. As an approach to identify novel cellular genes which are activated or repressed by stimuli that reactivate HSV from latency and hence may play a role in viral reactivation, RNA from explanted trigeminal ganglia (TG) was analyzed by differential display reverse transcription-PCR (DDRT-PCR). Nearly 50 cDNAs whose mRNA level was modified by the stress of explantation were isolated and sequenced. We present a listing of a spectrum of altered RNAs, including both known and unknown sequences. Five of those differentially displayed transcripts were identified as interferon-related murine TIS7 mRNA. These results were confirmed in both infected and uninfected ganglia by quantitative RNase protection assay and immunostaining. Alpha and beta interferons and interferon regulatory factor-1 (IRF-1) were also induced by explantation. In addition, we have identified sequences that correspond to IRF-1 consensus binding sites in both HSV type 1 origins of replication. Our findings suggest that physiological pathways that include these cellular factors may be involved in modulating HSV reactivation.
Assuntos
Proteínas de Ligação a DNA/genética , Regulação Viral da Expressão Gênica , Herpesvirus Humano 1/fisiologia , Proteínas Imediatamente Precoces/genética , Interferons/genética , Proteínas de Membrana/genética , Fosfoproteínas/genética , Reação em Cadeia da Polimerase/métodos , Ativação Viral/genética , Animais , Sequência de Bases , Proteínas de Ligação a DNA/biossíntese , Genes Supressores de Tumor , Proteínas Imediatamente Precoces/biossíntese , Fator Regulador 1 de Interferon , Interferons/biossíntese , Proteínas de Membrana/biossíntese , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Fosfoproteínas/biossíntese , Regulação para Cima , Latência ViralRESUMO
Herpes simplex virus (HSV) replicates in peripheral tissues and forms latent infections in neurons of the peripheral nervous system. It can be reactivated from latency by various stimuli to cause recurrent disease. During lytic infection in tissue culture cells, there is a well-described temporal pattern of (i) immediate-early, (ii) early, and (iii) late gene expression. However, latency is characterized by little if any expression of genes of the lytic cycle of infection. During reactivation, the pattern of gene expression is presumed to be similar to that during the lytic cycle in tissue culture, though recent work of W. P. Halford et al. (J. Virol. 70:5051-5060, 1996) and P. F. Nichol et al. (J. Virol. 70:5476-5486, 1996) suggests that it is modified in neuronal cell cultures. We have used the mouse trigeminal ganglion explant model and reverse transcription-PCR to determine the pattern of viral and cellular gene expression during reactivation. Surprisingly, the pattern of viral gene expression during lytic infection of cell cultures is not seen during reactivation. During reactivation, early viral transcripts were detected before immediate-early transcripts. The possibility that a cellular factor upregulates early genes during the initial reactivation stimulus is discussed.
