Reisman Lab Publications

Uttenbogaard, M.N., Giebler, H.A., Reisman, D., and Nyborg, J.K. 1995. Transcriptional repression of p53 by the human T-cell leukemia vitus type I tax protein. J. Biol. Chem. 270, 28503-28506.

The HTLV-I oncoprotein Tax is both an activator and repressor of a wide variety of viral and cellular genes. Deregulation of transcription by Tax is mediated through interaction with a variety of structurally unrelated cellular transcription factors, as Tax does not bind DNA in a sequence specific manner. We have recently demonstrated that members of the basic helix-loop-helix (bHLH) family of transcription factors, which play a critical role in progression through the cell cycle, mediate Tax repression of gene expression. In this report, we extend these studies to show that Tax represses transcription of the p53 gene, and that the repression requires a functional c-Myc or USF recognition sequence in the promoter. Loss or inactivation of the tumor suppressor p53 has previously been shown to be causually associated with oncogenic transformation. Together, these results suggest that Tax may promote malignant transformation through repression of the p53 gene.