LAT and infection: However, q-RT-PCR detection using primers specific for the LAT mRNA performed in the CNS, spinal cord and trigeminal nerve of mice sacrificed at 3 months after infection suggested that the expression of LAT was significantly lower in the CNS of UL7-MU-infected mice than in mice infected with the WT virus (Fig. 5b); moreover, LAT mRNA expression levels in the spinal cord and trigeminal nerve were approximately 2-fold lower in UL7-MU-infected mice than in mice infected with the WT strain (Fig. 5d and f).