Functions as a transcriptional repressor through its association with the NuRD complex. Recruits the NuRD complex to the promoter of MDM2, leading to the repression of MDM2 transcription and subsequent stability of p53/TP53 (By similarity). Homooligomer; mediated by the BTB domain. Interacts with the NuRD complex. Interacts (via C-terminal part) with HDAC2. Interacts (via BTB domain) with MTA1, MTA2 and MTA3. Predominantly associated with chromatin.