Altered chromatin higher-order structure in cells infected by herpes simplex virus type 1.

In cells infected by herpesviruses chromosomal aberrations such as breaks and constrictions are commonly observed. Previous studies have shown that chromatin modifications in cells infected by herpes simplex virus type 1 (HSV-1) are not due to extensive breakdown of host-cell DNA or disruption of nucleosomal structure. We have previously shown that infection by HSV-1 induces single-stranded breaks in the host-cell DNA in a time-dependent fashion. Here we report that the early DNA damage observed in virus-infected cells is related to modifications in the higher-order structure of host-cell chromatin. Such modifications seem to be of a more permanent nature than the DNA single-stranded breaks.