FIG. 2.

(A) Sequence alignment for UNG proteins encoded by viruses (CMV, HSV-1, and vaccinia virus) and humans. Regions of identity are shaded; regions of similarity are shown in blocks. Asterisks denote the residues which are known to abrogate human UNG activity (29). (B) RNA blot of total cellular RNA (10 μg/lane) isolated from uninfected, actively dividing cells (lane 1) and confluent, serum-starved cells (lane 2), hybridized with a biotinylated antisense riboprobe to human UNG. The arrow indicates the position of the UNG transcript; positions of the rRNA subunits are indicated on the left. rRNA was equivalent in all lanes (data not shown).