FIG 3.

Expression of gK, UL20, ICP0, and gB transcripts in cornea and TG of SPP-inducible knockout and ocularly infected mice. Tamoxifen- or corn oil-treated SPP^flox/flox CreERT₂^+/+ mice were ocularly infected with 2 × 10⁵ PFU/eye of HSV-1 strain McKrae. The levels of gK, UL20, ICP0, and gB transcripts in the cornea and TG were determined on days 3 and 5 p.i. by quantitative RT-PCR. In each experiment, the estimated relative copy numbers of HSV-1 UL20, gK, and gB were calculated using standard curves generated from pUL20 (54), pAC-gB1 (75), pAc-gK1 (3), and pcDNA3.1-ICP0 (76). Briefly, a DNA template, serially diluted 10-fold such that 5 μl contained from 10³ to 10¹¹ copies of each plasmid, was subjected to TaqMan PCR with the same primer set. The copy number for each reaction product was determined by comparing the C_T of each sample to the threshold cycle of the standard. GAPDH expression was used to normalize the relative expression of each transcript in the cornea and TG of infected mice. Each bar represents the mean ± standard errors of the mean from five mouse corneas or TG, as follows: gK (A), UL20 (B), ICP0 (C), and gB (D).