Human papillomavirus type 16 E6 protein up-regulates the expression of the high mobility group protein HMG-I(Y) gene in mouse 10T1/2 cells

Using a differential hybridization technique, we have identified a mouse cellular gene, high mobility group protein HMG-I(Y), whose expression is up-regulated by the E6 protein of human papillomavirus (HPV) type 16. This gene was overexpressed in E6-expressing mouse 10T1/2 cells, but not in G418-resistant 10T1/2 cells. The expression of the HMG-I(Y) gene was up-regulated by the transient expression of E6 from a zinc-inducible human metallothionein-IIA gene promoter. Expression was found to be more efficient at a confluent cell density than at a subconfluent cell density. The up-regulation of HMG-I(Y) gene expression by E6, in particular at a confluent cell density, may be part of an altered genetic program in host cells infected with HPV-16.