Prostate Apoptosis Response 4 (PAR4)

PAR4 is a WT1-interacting protein that itself functions as a transcriptional repressor. It contains a putative leucine zipper domain which interacts with the zinc finger DNA binding domain of WT1. This protein is specifically upregulated during apoptosis of prostate cells.The active domain of the Par-4 protein has been found to confer cancer resistance in transgenic mice without compromising normal viability or aging, and may have therapeutic significance.

WT1 and PAR4 interact specifically both in vitro and in vivo and that this interaction is mediated by the zinc fingers of WT1 and the leucine repeats of PAR4. Functional analyses showed that PAR4 inhibited transcription activated by WT1 and augmented WT1-mediated transcriptional repression.