Fig. 5.

N-protein RNA is expressed by primary astrocytes infected with SHBRV-17 but not CVS-N2c in culture. Primary mouse astrocytes were infected with either CVS-N2c or SHBRV-17, and N-protein mRNA levels were assessed by real-time RT-PCR and normalized to G3PDH mRNA levels in the sample as described in Materials and Methods. The results are expressed as the fold increase in N-protein RNA over time of culture with the amount of N protein-specific RNA in the input virus, represented as day 0, assigned a value of 1. SHBRV-17 N-protein RNA levels at days 2 and 3 of culture were significantly greater than the input level by ANOVA with Bonferroni's multiple comparison test (*, P < 0. 05).