Acts as a transcriptional repressor (PubMed:10688654, PubMed:24359566). Transcriptional repression may be mediated through recruitment of histone deacetylases to target promoters (PubMed:10688654). May play a role in myeloid maturation and in the development and/or maintenance of other differentiated tissues. Probable substrate-recognition component of an E3 ubiquitin-protein ligase complex which mediates the ubiquitination and subsequent proteasomal degradation of target proteins (PubMed:14528312).