Functional role of TTF‐1 binding sites in bovine thyroglobulin promoter

Autor: Javaux, Françoise, Bertaux, Fabien, Donda, Alena, Francis-Lang, Helen, Vassart, Gilbert, DiLauro, Roberto, Christophe, Daniel
Zdroj: FEBS Letters; April 1992, Vol. 300 Issue: 3 p222-226, 5p
Abstrakt: We have studied the binding of purified TTF‐1 on the bovine thyroglobulin gene promoter. DNase I footprinting experiments revealed three binding sites which corresponded in location to the A, B and C sites found in the rat thyroglobulin promoter. Mutants in the A and C regions showing reduced binding of TTF‐1, also exhibited largely decreased promoter activity in transient expression experiments in primary‐cultured dog thyrocytes. Two mutants in the B site that exhibited a reduced capacity to bind TTF‐1 also displayed a drastically affected transcriptional activity in transient assays. As in the rat, sites A and C only are critical for promoter activity, these results suggest that full occupancy of the B site is required for thyroglobulin promoter activity in the cow only.
Databáze: Supplemental Index