FIG. 7.

Downregulation of MHV-68 gene expression by NS-398. (A) BHK-21 cells were untreated (left panel) or pretreated with 5 μM NS-398 (right panel) before infection with wt MHV-68. Cells were maintained in medium containing 5 μM NS-398 during the infection and postinfection incubations (right panel). Total RNA was harvested 8 h postinfection, and labeled cDNA probe was generated for hybridization to MHV-68 DNA arrays. The ORFs are printed below each array element. (B) A STORM phosphorimager and ImageQuant system were used to quantitate the signal from the array elements corresponding to 73 known and predicted MHV-68 ORFs. GAPDH-normalized values from the array with NS-398 (A, right panel) were divided by the corresponding GAPDH-normalized values from the untreated array (A, left panel) to derive the fold inhibition of gene expression relative to the untreated level for each array element. These values and their corresponding MHV-68 ORFs are ordered in the bar graph based on increasing fold inhibition of gene expression relative to the untreated level. Statistical significance of differences in expression was assessed by paired t test.