Removal of YY1 binding sites in HPV 16 LCR increases viral transforming activities on mouse fibroblasts
Dong, X.; Liu, H.; Pfister, H.
Zhonghua Shi Yan he Lin Chuang Bing du Xue Za Zhi 13(1): 5-8
1999
ISSN/ISBN: 1003-9279 PMID: 12759941 Document Number: 505329
To study the effect of removal of YY1 binding sites within the LCR region of HPV 16 on viral transforming activity. Previously we had generated new plasmids carrying HPV 16 whole genome, which contained naturally occurred mutated LCR sequences. The viral transforming abilities on mouse fibroblasts were evaluated in anchorage-independent assays, while the expression and activity of YY1 protein in fibroblasts were tested with EMSA and luciferase assays. YY1 protein was expressed in mouse fibroblasts C127, with ability for DNA binding and repression on P97 activity. Both HPV 16 wild-type DNA and mutated DNAs were transfected into C127 cells and spread to the soft-agarose mediums after selecting with G 418. The growth numbers of the cells transfected with mutated HPV 16 DNAs were 2-10 fold more than that with wild-type HPV 16 DNA. Like in epithelial cells or cell lines, transcription regulator YY1 is widely expressed in rodent fibroblasts. Removal of YY1 binding motifs can elevate in the context of the whole genome, the anchorage independent growth ability and the transforming capacity of HPV 16 on the mouse fibroblasts.