A labile repressor acts through the NFkB-like binding sites of the human urokinase gene

Abstract

Transcription of the human urokinase type plasminogen activator (uPA ) gene in HeLa cells Is induced by phorbol myristate acetate (PMA ), interleukin-1 (IL-1) and tumor necrosis factor α (TNFα). The response to these factors is rapid, independent of new protein synthesis and amplified in the presence of an inhibitor of protein synthesis, indicating the presence of a labile repressor. A DNA element, similar to the binding site for the transcription factor NFkB, is located around - 1865 wIth respect to the start site of transcription in the uPA promoter and confers supennducibility by these agents in the presence of cycloheximide (CHX). A synthetic copy of this element confers superinducibilit..