Effect of rabies virus infection on gene expression in mouse brain

Abstract

A variety of molecular genetic approaches were used to study the effect of rabies virus (RV) infection on host gene expression in mouse brain. The down-regulation of gene expression was found to be a major effect of RV infection by using subtraction hybridization. However, a combination of techniques identified approximately 39 genes activated by infection. These included genes involved in regulation of cell metabolism, protein synthesis, synaptic activity, and cell growth and differentiation. Northern blot analysis to monitor temporal activation of several of these genes following infection revealed essentially two patterns of activation: (i) an early response with up-regulation beginning within 3 days after infection and correlating with transcription of RV nuclear protein; and (ii) a late response with enhanced expression occurring at days 6 -7 after infection and associated with peak RV replication. The gene activation patterns and the known functions of their products suggest that a number of host genes may be involved in the replication and spread of RV in the brain.T he outcome of rabies virus (RV) infection is determined by the convergence of several different virus-host interactions, including those that contribute to virus replication and spread, pathogenic effects on cells, and antiviral responses. RV is particularly suitable for the study of virus-host interactions because of the small size of its genome and its high specificity for infection of neurons. Nevertheless, the mechanisms involved in the disease process are undoubtedly complex. For example, the virus, which uses the neuronal network to spread within the host, must initially replicate in neurons without causing significant functional impairment that would compromise the infection cycle (1). While there is some understanding of the roles of viral proteins in rabies pathogenesis, the contribution of host factors to RV transcription͞replication and axonal͞trans-synaptic spread remain unknown. Various technologies are now available to identify host genes that might be essential for the life cycle of RV, important in antiviral defense, or activated nonspecifically in RV infection (2-4). Because each technology is suited for the detection of different classes of genes and different levels of gene expression, we used a variety of assays, including differential display (DD), cDNA array hybridization, subtraction hybridization (SH), and restriction fragment differential display (RFDD), to assess gene expression in rabies-infected mouse brain. With these approaches, we have revealed the effects of rabies infection on select gene expression patterns in the brain. Based on known functional properties of several gene products as well as the timing of their up-regulation after infection, we discuss possible contributions of host genes to the pathogenesis of rabies. Materials and MethodsVirus Infection of Mice. Female, 6-to 8-week-old Swiss Webster mice were purchased from Taconic Farms. Mice were maintained under pathogen-free conditions and used to 10 w...

Common host genes are activated in mouse brain by Japanese encephalitis and rabies viruses

“…Restriction enzyme digestion and DNA sequence analysis of plasmids isolated from 100 transformants resulted in the isolation of nine different genes whose identity was established by searching the GenBank nucleotide database (Table 1). Some of these genes have been reported to be upregulated in the CNS by RV (Prosniak et al, 2001) and SINV (Johnston et al, 2001). Upregulation of the host CNS genes during JEV infection was further confirmed by Northern blot analysis of RNA isolated from JEV-infected mice at days 3 and 6 p.i.…”

“…Upregulation of the host CNS genes during JEV infection was further confirmed by Northern blot analysis of RNA isolated from JEV-infected mice at days 3 and 6 p.i. Mice injected with saline and sacrificed 6 days later as well as *These genes are known to be induced in the CNS by RV (Prosniak et al, 2001) as well as by SINV (Johnston et al, 2001).…”

“…Such studies have been reported only for a few neurotropic viruses. At least 39 genes are activated in the CNS during rabies virus (RV) infection (Prosniak et al, 2001). In the case of Sindbis virus (SINV), the study of changes in CNS gene expression during virulent and avirulent infection has led to the identification of specific host genes that may play a role in the protective or pathological host response (Johnston et al, 2001).…”

Distribución de calbindina y parvoalbúmina y efecto del virus de la rabia sobre su expresión en la médula espinal de ratones

“…En un estudio de biología molecular llevado a cabo en ratones inoculados con virus fijo de la rabia, se encontró que el virus induce la caída en la expresión de la mayoría de genes estudiados (no estaban incluidos CB y PV), pero un pequeño porcentaje de ellos aumentó su expresión (36). De esta manera se puede concluir que la infección del sistema nervioso con el virus de la rabia puede eventualmente aumentar la expresión de algunas proteínas.…”

Efecto de la infección por el virus de la rabia sobre la expresión de parvoalbúmina, calbindina y calretinina en la corteza cerebral de ratones.

“…En un estudio reciente, una cepa del virus 'fijo' de la rabia inoculada en ratones provocó la disminución en la expresión del 90% de los genes evaluados, pero en el 1,4% (39 genes) aumentó la expresión, incluso en genes involucrados en la regulación del metabolismo celular, síntesis de proteínas y actividad sináptica, todos ellos relacionados con la necesidad del virus de reproducirse y diseminarse a otras células (45).…”