A novel zinc finger transcriptional repressor, ZNF224, interacts with the negative regulatory element (AldA-NRE) and inhibits gene expression

The interaction between the negative cis-element (AldA-NRE) and p97 repressor nuclear protein is a key step in modulating transcription ofthe human and mouse aldolase A (AldA) gene during the cell cycle and di¡erentiation. In an attempt to clarify the role of transcriptional repression in regulating gene expression, we puri¢ed, from HeLa cells, the nuclear protein that speci¢cally binds to the AldA negative regulatory element (NRE). Matrix-assisted laser desorption ionization-time of£ight analysis and examination ofprotein pro¢les from the SwissProt database revealed that the previously de¢ned p97 repressor is ZNF224, a zinc ¢nger protein. We demonstrate that ZNF224, a Kruppel-like zinc ¢nger transcription factor, is the repressor protein that speci¢cally binds to the negative cis-element AldA-NRE and a¡ects the AldA-NREmediated transcription.