Cross talk between expression of the human T-cell leukemia virus type 1 Tax transactivator and the oncogenic bHLH transcription factor TAL1.

ABSTRACT: The human T-cell leukemia virus type 1 (HTLV-1) Tax transactivator is known to induce or repress various cellular genes, several of them encoding transcription factors. As Tax is known to deregulate various basic bHLH factors, we looked more specifically at its effect on TAL1 (T-cell acute lymphoblastic leukemia 1), also known as SCL (stem cell leukemia). Indeed, TAL1 is deregulated in a high percentage of T-cell acute lymphoblastic leukemia cells, and its oncogenic properties are well-established. Here we show that Tax induces transcription of this proto-oncogene by stimulating the activity of the TAL1 gene promoter 1b, through both the CREB and NF-kappaB pathways. It was also observed that TAL1 upregulates HTLV-1 promoter activity, in either the presence or the absence of Tax. The viral

SUBMITTER: Terme JM 

PROVIDER: S-EPMC2519563 | biostudies-literature | 2008 Aug

REPOSITORIES: biostudies-literature