Overexpression of Mxi1 inhibits the induction of the human ornithine decarboxylase gene by the Myc/Max protein complex

摘要: We have previously shown that the Myc/Max protein complex plays a role in growth-associated expression of human ornithine decarboxylase gene. Mxi1 and Mad, novel Max-associated proteins been identified to form heterodimers with Max which bind efficiently consensus recognition sequence, CACGTG, vitro. However, formation Max/Mxi1 or Max/Mad results reduction dependent transcriptional activation reporter plasmid constructs containing element. In light evidence ODC is transcriptionally regulated vitro vivo by potential Mad as antagonists Myc transactivation activity, we set out determine if one these associated proteins, Mxi1, could affect regulation this was correlated growth status. Our show overexpression does fact inhibit gene dose-dependent manner both addition, presented shows levels are up-regulated during long term quiescence down-regulated following stimulation serum. These suggest alterations such can modulate critical functional complexes. This alter Myc-regulated targets consequence genes essential for initiation and/or maintenance growth.