Transcription repressor that specifically binds the 5′-GGAG[GA]A[GA]A-3′ consensus sequence. Represses transcription by recruiting the chromatin multiprotein complex NuRD to target promoters. Negatively regulates expression of EGFR, a gene involved in cell proliferation, survival and migration. Its ability to repress genes of the EGFR pathway suggest it may act as a tumor suppressor. Able to suppress breast carcinogenesis. ; [Isoform 4]: Antagonizes the transcription repression by isoform 1 by competing for the binding of the NuRD complex. Does not bind DNA.