T3-activation of the Rat Growth Hormone Gene is Inhibited by a Zinc Finger/Homeodomain Protein

ANA MARIA DE LOS A. CABANILLAS; GREG SMITH,; DOUGLAS DARLING,

Elsevier

Año: 2001 vol. 181 p. 131 - 131

b> Abstract Since the transcription factor Zfhep is expressed in somatotropes and binds the rat growth hormone (rGH) gene T3-response element (TRE), we investigated whether Zfhep regulates the response of this gene to T3. In cotransfection experiments, Zfhep did not regulate the native rGH promoter in the absence of T3. However, Zfhep repressed T3-mediated activation significantly in either GH3 or JEG-3 cells. Up to 70% repression was mediated through the rGH TRE in a heterologous promoter (thymidine kinase), but was not observed with the idealized DR4 or chicken lysozyme F2