A negative regulatory element in the promoter of the human alpha 1-antitrypsin gene.

A "minimal tissue-specific element" of the human alpha 1-antitrypsin (alpha 1-AT) gene promoter, located in the -137/-37 region, is able to drive hepatoma-specific transcription from the heterologous SV40 promoter. Here we show that, in HeLa cells, this element is inactivated by a negative regulatory mechanism. This negative control can be overcome by deletion or mutation of two specific DNA domains.