FIG 3.

Mutant HSV-1 with drastically reduced miR-H2 expression. (A) 293T cells were either mock infected or infected with WT (WT-BAC) or MH2 virus at an MOI of 10 for 18 h, followed by Northern blotting. The probes used for hybridization are shown to the left, and the positions of miRNA species (pre- and mature) are indicated to the right. (B) “miR-MH2” expressed in MH2-infected cells is present at levels 150-fold below the level of miR-H2 in WT-infected cells. qRT-PCR assays for miR-H2 (circles) and “miR-MH2” (squares) were performed on duplicate gel-extracted short RNA samples from 293T cells infected with WT (left) or MH2 (right) virus. Signals detected in WT-infected cells by the “miR-MH2” assay and in MH2-infected cells by the miR-H2 assay were either very low or not detectable (nd). Expression levels were normalized to that of host miRNA let-7a. Bars represent mean values.